diff options
Diffstat (limited to 'kernel')
156 files changed, 7108 insertions, 3029 deletions
diff --git a/kernel/Kconfig.kexec b/kernel/Kconfig.kexec index 37e488d5b4..946dffa048 100644 --- a/kernel/Kconfig.kexec +++ b/kernel/Kconfig.kexec @@ -110,7 +110,7 @@ config CRASH_DUMP For more details see Documentation/admin-guide/kdump/kdump.rst For s390, this option also enables zfcpdump. - See also <file:Documentation/s390/zfcpdump.rst> + See also <file:Documentation/arch/s390/zfcpdump.rst> config CRASH_HOTPLUG bool "Update the crash elfcorehdr on system configuration changes" diff --git a/kernel/acct.c b/kernel/acct.c index 1a9f929fe6..986c8214da 100644 --- a/kernel/acct.c +++ b/kernel/acct.c @@ -246,7 +246,7 @@ static int acct_on(struct filename *pathname) filp_close(file, NULL); return PTR_ERR(internal); } - err = __mnt_want_write(internal); + err = mnt_get_write_access(internal); if (err) { mntput(internal); kfree(acct); @@ -271,7 +271,7 @@ static int acct_on(struct filename *pathname) old = xchg(&ns->bacct, &acct->pin); mutex_unlock(&acct->lock); pin_kill(old); - __mnt_drop_write(mnt); + mnt_put_write_access(mnt); mntput(mnt); return 0; } diff --git a/kernel/audit.c b/kernel/audit.c index 16205dd298..9c8e5f732c 100644 --- a/kernel/audit.c +++ b/kernel/audit.c @@ -487,15 +487,19 @@ static void auditd_conn_free(struct rcu_head *rcu) * @pid: auditd PID * @portid: auditd netlink portid * @net: auditd network namespace pointer + * @skb: the netlink command from the audit daemon + * @ack: netlink ack flag, cleared if ack'd here * * Description: * This function will obtain and drop network namespace references as * necessary. Returns zero on success, negative values on failure. */ -static int auditd_set(struct pid *pid, u32 portid, struct net *net) +static int auditd_set(struct pid *pid, u32 portid, struct net *net, + struct sk_buff *skb, bool *ack) { unsigned long flags; struct auditd_connection *ac_old, *ac_new; + struct nlmsghdr *nlh; if (!pid || !net) return -EINVAL; @@ -507,6 +511,13 @@ static int auditd_set(struct pid *pid, u32 portid, struct net *net) ac_new->portid = portid; ac_new->net = get_net(net); + /* send the ack now to avoid a race with the queue backlog */ + if (*ack) { + nlh = nlmsg_hdr(skb); + netlink_ack(skb, nlh, 0, NULL); + *ack = false; + } + spin_lock_irqsave(&auditd_conn_lock, flags); ac_old = rcu_dereference_protected(auditd_conn, lockdep_is_held(&auditd_conn_lock)); @@ -1200,7 +1211,8 @@ static int audit_replace(struct pid *pid) return auditd_send_unicast_skb(skb); } -static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) +static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh, + bool *ack) { u32 seq; void *data; @@ -1293,7 +1305,8 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) /* register a new auditd connection */ err = auditd_set(req_pid, NETLINK_CB(skb).portid, - sock_net(NETLINK_CB(skb).sk)); + sock_net(NETLINK_CB(skb).sk), + skb, ack); if (audit_enabled != AUDIT_OFF) audit_log_config_change("audit_pid", new_pid, @@ -1538,9 +1551,10 @@ static int audit_receive_msg(struct sk_buff *skb, struct nlmsghdr *nlh) * Parse the provided skb and deal with any messages that may be present, * malformed skbs are discarded. */ -static void audit_receive(struct sk_buff *skb) +static void audit_receive(struct sk_buff *skb) { struct nlmsghdr *nlh; + bool ack; /* * len MUST be signed for nlmsg_next to be able to dec it below 0 * if the nlmsg_len was not aligned @@ -1553,9 +1567,12 @@ static void audit_receive(struct sk_buff *skb) audit_ctl_lock(); while (nlmsg_ok(nlh, len)) { - err = audit_receive_msg(skb, nlh); - /* if err or if this message says it wants a response */ - if (err || (nlh->nlmsg_flags & NLM_F_ACK)) + ack = nlh->nlmsg_flags & NLM_F_ACK; + err = audit_receive_msg(skb, nlh, &ack); + + /* send an ack if the user asked for one and audit_receive_msg + * didn't already do it, or if there was an error. */ + if (ack || err) netlink_ack(skb, nlh, err, NULL); nlh = nlmsg_next(nlh, &len); diff --git a/kernel/audit_tree.c b/kernel/audit_tree.c index e867c17d3f..1b07e6f12a 100644 --- a/kernel/audit_tree.c +++ b/kernel/audit_tree.c @@ -34,7 +34,7 @@ struct audit_chunk { struct list_head list; struct audit_tree *owner; unsigned index; /* index; upper bit indicates 'will prune' */ - } owners[]; + } owners[] __counted_by(count); }; struct audit_tree_mark { @@ -87,8 +87,8 @@ static struct task_struct *prune_thread; * that makes a difference. Some. */ -static struct fsnotify_group *audit_tree_group; -static struct kmem_cache *audit_tree_mark_cachep __read_mostly; +static struct fsnotify_group *audit_tree_group __ro_after_init; +static struct kmem_cache *audit_tree_mark_cachep __ro_after_init; static struct audit_tree *alloc_tree(const char *s) { diff --git a/kernel/bpf/arraymap.c b/kernel/bpf/arraymap.c index 9bfad7e969..c9843dde69 100644 --- a/kernel/bpf/arraymap.c +++ b/kernel/bpf/arraymap.c @@ -871,7 +871,7 @@ int bpf_fd_array_map_update_elem(struct bpf_map *map, struct file *map_file, return 0; } -static long fd_array_map_delete_elem(struct bpf_map *map, void *key) +static long __fd_array_map_delete_elem(struct bpf_map *map, void *key, bool need_defer) { struct bpf_array *array = container_of(map, struct bpf_array, map); void *old_ptr; @@ -890,13 +890,18 @@ static long fd_array_map_delete_elem(struct bpf_map *map, void *key) } if (old_ptr) { - map->ops->map_fd_put_ptr(map, old_ptr, true); + map->ops->map_fd_put_ptr(map, old_ptr, need_defer); return 0; } else { return -ENOENT; } } +static long fd_array_map_delete_elem(struct bpf_map *map, void *key) +{ + return __fd_array_map_delete_elem(map, key, true); +} + static void *prog_fd_array_get_ptr(struct bpf_map *map, struct file *map_file, int fd) { @@ -925,13 +930,13 @@ static u32 prog_fd_array_sys_lookup_elem(void *ptr) } /* decrement refcnt of all bpf_progs that are stored in this map */ -static void bpf_fd_array_map_clear(struct bpf_map *map) +static void bpf_fd_array_map_clear(struct bpf_map *map, bool need_defer) { struct bpf_array *array = container_of(map, struct bpf_array, map); int i; for (i = 0; i < array->map.max_entries; i++) - fd_array_map_delete_elem(map, &i); + __fd_array_map_delete_elem(map, &i, need_defer); } static void prog_array_map_seq_show_elem(struct bpf_map *map, void *key, @@ -1072,7 +1077,7 @@ static void prog_array_map_clear_deferred(struct work_struct *work) { struct bpf_map *map = container_of(work, struct bpf_array_aux, work)->map; - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, true); bpf_map_put(map); } @@ -1222,7 +1227,7 @@ static void perf_event_fd_array_release(struct bpf_map *map, for (i = 0; i < array->map.max_entries; i++) { ee = READ_ONCE(array->ptrs[i]); if (ee && ee->map_file == map_file) - fd_array_map_delete_elem(map, &i); + __fd_array_map_delete_elem(map, &i, true); } rcu_read_unlock(); } @@ -1230,7 +1235,7 @@ static void perf_event_fd_array_release(struct bpf_map *map, static void perf_event_fd_array_map_free(struct bpf_map *map) { if (map->map_flags & BPF_F_PRESERVE_ELEMS) - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } @@ -1266,7 +1271,7 @@ static void cgroup_fd_array_put_ptr(struct bpf_map *map, void *ptr, bool need_de static void cgroup_fd_array_free(struct bpf_map *map) { - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } @@ -1311,7 +1316,7 @@ static void array_of_map_free(struct bpf_map *map) * is protected by fdget/fdput. */ bpf_map_meta_free(map->inner_map_meta); - bpf_fd_array_map_clear(map); + bpf_fd_array_map_clear(map, false); fd_array_map_free(map); } diff --git a/kernel/bpf/bpf_iter.c b/kernel/bpf/bpf_iter.c index 96856f130c..0fae791641 100644 --- a/kernel/bpf/bpf_iter.c +++ b/kernel/bpf/bpf_iter.c @@ -782,9 +782,7 @@ struct bpf_iter_num_kern { int end; /* final value, exclusive */ } __aligned(8); -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "Global functions as their definitions will be in vmlinux BTF"); +__bpf_kfunc_start_defs(); __bpf_kfunc int bpf_iter_num_new(struct bpf_iter_num *it, int start, int end) { @@ -793,8 +791,6 @@ __bpf_kfunc int bpf_iter_num_new(struct bpf_iter_num *it, int start, int end) BUILD_BUG_ON(sizeof(struct bpf_iter_num_kern) != sizeof(struct bpf_iter_num)); BUILD_BUG_ON(__alignof__(struct bpf_iter_num_kern) != __alignof__(struct bpf_iter_num)); - BTF_TYPE_EMIT(struct btf_iter_num); - /* start == end is legit, it's an empty range and we'll just get NULL * on first (and any subsequent) bpf_iter_num_next() call */ @@ -845,4 +841,4 @@ __bpf_kfunc void bpf_iter_num_destroy(struct bpf_iter_num *it) s->cur = s->end = 0; } -__diag_pop(); +__bpf_kfunc_end_defs(); diff --git a/kernel/bpf/bpf_struct_ops.c b/kernel/bpf/bpf_struct_ops.c index fdc3e8705a..db6176fb64 100644 --- a/kernel/bpf/bpf_struct_ops.c +++ b/kernel/bpf/bpf_struct_ops.c @@ -615,7 +615,10 @@ static void __bpf_struct_ops_map_free(struct bpf_map *map) if (st_map->links) bpf_struct_ops_map_put_progs(st_map); bpf_map_area_free(st_map->links); - bpf_jit_free_exec(st_map->image); + if (st_map->image) { + bpf_jit_free_exec(st_map->image); + bpf_jit_uncharge_modmem(PAGE_SIZE); + } bpf_map_area_free(st_map->uvalue); bpf_map_area_free(st_map); } @@ -657,6 +660,7 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) struct bpf_struct_ops_map *st_map; const struct btf_type *t, *vt; struct bpf_map *map; + int ret; st_ops = bpf_struct_ops_find_value(attr->btf_vmlinux_value_type_id); if (!st_ops) @@ -681,12 +685,27 @@ static struct bpf_map *bpf_struct_ops_map_alloc(union bpf_attr *attr) st_map->st_ops = st_ops; map = &st_map->map; + ret = bpf_jit_charge_modmem(PAGE_SIZE); + if (ret) { + __bpf_struct_ops_map_free(map); + return ERR_PTR(ret); + } + + st_map->image = bpf_jit_alloc_exec(PAGE_SIZE); + if (!st_map->image) { + /* __bpf_struct_ops_map_free() uses st_map->image as flag + * for "charged or not". In this case, we need to unchange + * here. + */ + bpf_jit_uncharge_modmem(PAGE_SIZE); + __bpf_struct_ops_map_free(map); + return ERR_PTR(-ENOMEM); + } st_map->uvalue = bpf_map_area_alloc(vt->size, NUMA_NO_NODE); st_map->links = bpf_map_area_alloc(btf_type_vlen(t) * sizeof(struct bpf_links *), NUMA_NO_NODE); - st_map->image = bpf_jit_alloc_exec(PAGE_SIZE); - if (!st_map->uvalue || !st_map->links || !st_map->image) { + if (!st_map->uvalue || !st_map->links) { __bpf_struct_ops_map_free(map); return ERR_PTR(-ENOMEM); } @@ -907,4 +926,3 @@ err_out: kfree(link); return err; } - diff --git a/kernel/bpf/btf.c b/kernel/bpf/btf.c index a31704a6bb..15d71d2986 100644 --- a/kernel/bpf/btf.c +++ b/kernel/bpf/btf.c @@ -3293,6 +3293,8 @@ static int btf_find_kptr(const struct btf *btf, const struct btf_type *t, type = BPF_KPTR_UNREF; else if (!strcmp("kptr", __btf_name_by_offset(btf, t->name_off))) type = BPF_KPTR_REF; + else if (!strcmp("percpu_kptr", __btf_name_by_offset(btf, t->name_off))) + type = BPF_KPTR_PERCPU; else return -EINVAL; @@ -3308,10 +3310,10 @@ static int btf_find_kptr(const struct btf *btf, const struct btf_type *t, return BTF_FIELD_FOUND; } -static const char *btf_find_decl_tag_value(const struct btf *btf, - const struct btf_type *pt, - int comp_idx, const char *tag_key) +const char *btf_find_decl_tag_value(const struct btf *btf, const struct btf_type *pt, + int comp_idx, const char *tag_key) { + const char *value = NULL; int i; for (i = 1; i < btf_nr_types(btf); i++) { @@ -3325,9 +3327,14 @@ static const char *btf_find_decl_tag_value(const struct btf *btf, continue; if (strncmp(__btf_name_by_offset(btf, t->name_off), tag_key, len)) continue; - return __btf_name_by_offset(btf, t->name_off) + len; + /* Prevent duplicate entries for same type */ + if (value) + return ERR_PTR(-EEXIST); + value = __btf_name_by_offset(btf, t->name_off) + len; } - return NULL; + if (!value) + return ERR_PTR(-ENOENT); + return value; } static int @@ -3345,7 +3352,7 @@ btf_find_graph_root(const struct btf *btf, const struct btf_type *pt, if (t->size != sz) return BTF_FIELD_IGNORE; value_type = btf_find_decl_tag_value(btf, pt, comp_idx, "contains:"); - if (!value_type) + if (IS_ERR(value_type)) return -EINVAL; node_field_name = strstr(value_type, ":"); if (!node_field_name) @@ -3457,6 +3464,7 @@ static int btf_find_struct_field(const struct btf *btf, break; case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: ret = btf_find_kptr(btf, member_type, off, sz, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) @@ -3523,6 +3531,7 @@ static int btf_find_datasec_var(const struct btf *btf, const struct btf_type *t, break; case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: ret = btf_find_kptr(btf, var_type, off, sz, idx < info_cnt ? &info[idx] : &tmp); if (ret < 0) @@ -3783,6 +3792,7 @@ struct btf_record *btf_parse_fields(const struct btf *btf, const struct btf_type break; case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: ret = btf_parse_kptr(btf, &rec->fields[i], &info_arr[i]); if (ret < 0) goto end; @@ -6949,7 +6959,7 @@ int btf_check_subprog_call(struct bpf_verifier_env *env, int subprog, * (either PTR_TO_CTX or SCALAR_VALUE). */ int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog, - struct bpf_reg_state *regs) + struct bpf_reg_state *regs, bool is_ex_cb) { struct bpf_verifier_log *log = &env->log; struct bpf_prog *prog = env->prog; @@ -7006,7 +7016,7 @@ int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog, tname, nargs, MAX_BPF_FUNC_REG_ARGS); return -EINVAL; } - /* check that function returns int */ + /* check that function returns int, exception cb also requires this */ t = btf_type_by_id(btf, t->type); while (btf_type_is_modifier(t)) t = btf_type_by_id(btf, t->type); @@ -7055,6 +7065,14 @@ int btf_prepare_func_args(struct bpf_verifier_env *env, int subprog, i, btf_type_str(t), tname); return -EINVAL; } + /* We have already ensured that the callback returns an integer, just + * like all global subprogs. We need to determine it only has a single + * scalar argument. + */ + if (is_ex_cb && (nargs != 1 || regs[BPF_REG_1].type != SCALAR_VALUE)) { + bpf_log(log, "exception cb only supports single integer argument\n"); + return -EINVAL; + } return 0; } diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index ac37bd53ae..491d20038c 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -1458,7 +1458,7 @@ EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk); * @flags: Pointer to u32 which contains higher bits of BPF program * return value (OR'ed together). * - * socket is expected to be of type INET or INET6. + * socket is expected to be of type INET, INET6 or UNIX. * * This function will return %-EPERM if an attached program is found and * returned value != 1 during execution. In all other cases, 0 is returned. @@ -1482,7 +1482,8 @@ int __cgroup_bpf_run_filter_sock_addr(struct sock *sk, /* Check socket family since not all sockets represent network * endpoint (e.g. AF_UNIX). */ - if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6) + if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6 && + sk->sk_family != AF_UNIX) return 0; if (!ctx.uaddr) { @@ -1799,7 +1800,7 @@ static bool sockopt_buf_allocated(struct bpf_sockopt_kern *ctx, } int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level, - int *optname, char __user *optval, + int *optname, sockptr_t optval, int *optlen, char **kernel_optval) { struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); @@ -1822,7 +1823,8 @@ int __cgroup_bpf_run_filter_setsockopt(struct sock *sk, int *level, ctx.optlen = *optlen; - if (copy_from_user(ctx.optval, optval, min(*optlen, max_optlen)) != 0) { + if (copy_from_sockptr(ctx.optval, optval, + min(*optlen, max_optlen))) { ret = -EFAULT; goto out; } @@ -1889,8 +1891,8 @@ out: } int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, - int optname, char __user *optval, - int __user *optlen, int max_optlen, + int optname, sockptr_t optval, + sockptr_t optlen, int max_optlen, int retval) { struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data); @@ -1917,8 +1919,8 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, * one that kernel returned as well to let * BPF programs inspect the value. */ - - if (get_user(ctx.optlen, optlen)) { + if (copy_from_sockptr(&ctx.optlen, optlen, + sizeof(ctx.optlen))) { ret = -EFAULT; goto out; } @@ -1929,8 +1931,8 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, } orig_optlen = ctx.optlen; - if (copy_from_user(ctx.optval, optval, - min(ctx.optlen, max_optlen)) != 0) { + if (copy_from_sockptr(ctx.optval, optval, + min(ctx.optlen, max_optlen))) { ret = -EFAULT; goto out; } @@ -1944,7 +1946,8 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, if (ret < 0) goto out; - if (optval && (ctx.optlen > max_optlen || ctx.optlen < 0)) { + if (!sockptr_is_null(optval) && + (ctx.optlen > max_optlen || ctx.optlen < 0)) { if (orig_optlen > PAGE_SIZE && ctx.optlen >= 0) { pr_info_once("bpf getsockopt: ignoring program buffer with optlen=%d (max_optlen=%d)\n", ctx.optlen, max_optlen); @@ -1956,11 +1959,12 @@ int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level, } if (ctx.optlen != 0) { - if (optval && copy_to_user(optval, ctx.optval, ctx.optlen)) { + if (!sockptr_is_null(optval) && + copy_to_sockptr(optval, ctx.optval, ctx.optlen)) { ret = -EFAULT; goto out; } - if (put_user(ctx.optlen, optlen)) { + if (copy_to_sockptr(optlen, &ctx.optlen, sizeof(ctx.optlen))) { ret = -EFAULT; goto out; } @@ -2533,10 +2537,13 @@ cgroup_common_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_CGROUP_SOCK_OPS: case BPF_CGROUP_UDP4_RECVMSG: case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UNIX_RECVMSG: case BPF_CGROUP_INET4_GETPEERNAME: case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_UNIX_GETPEERNAME: case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_INET6_GETSOCKNAME: + case BPF_CGROUP_UNIX_GETSOCKNAME: return NULL; default: return &bpf_get_retval_proto; @@ -2548,10 +2555,13 @@ cgroup_common_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog) case BPF_CGROUP_SOCK_OPS: case BPF_CGROUP_UDP4_RECVMSG: case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UNIX_RECVMSG: case BPF_CGROUP_INET4_GETPEERNAME: case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_UNIX_GETPEERNAME: case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_INET6_GETSOCKNAME: + case BPF_CGROUP_UNIX_GETSOCKNAME: return NULL; default: return &bpf_set_retval_proto; diff --git a/kernel/bpf/cgroup_iter.c b/kernel/bpf/cgroup_iter.c index 810378f04f..f04a468cf6 100644 --- a/kernel/bpf/cgroup_iter.c +++ b/kernel/bpf/cgroup_iter.c @@ -282,7 +282,7 @@ static struct bpf_iter_reg bpf_cgroup_reg_info = { .ctx_arg_info_size = 1, .ctx_arg_info = { { offsetof(struct bpf_iter__cgroup, cgroup), - PTR_TO_BTF_ID_OR_NULL }, + PTR_TO_BTF_ID_OR_NULL | PTR_TRUSTED }, }, .seq_info = &cgroup_iter_seq_info, }; @@ -294,3 +294,66 @@ static int __init bpf_cgroup_iter_init(void) } late_initcall(bpf_cgroup_iter_init); + +struct bpf_iter_css { + __u64 __opaque[3]; +} __attribute__((aligned(8))); + +struct bpf_iter_css_kern { + struct cgroup_subsys_state *start; + struct cgroup_subsys_state *pos; + unsigned int flags; +} __attribute__((aligned(8))); + +__bpf_kfunc_start_defs(); + +__bpf_kfunc int bpf_iter_css_new(struct bpf_iter_css *it, + struct cgroup_subsys_state *start, unsigned int flags) +{ + struct bpf_iter_css_kern *kit = (void *)it; + + BUILD_BUG_ON(sizeof(struct bpf_iter_css_kern) > sizeof(struct bpf_iter_css)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_css_kern) != __alignof__(struct bpf_iter_css)); + + kit->start = NULL; + switch (flags) { + case BPF_CGROUP_ITER_DESCENDANTS_PRE: + case BPF_CGROUP_ITER_DESCENDANTS_POST: + case BPF_CGROUP_ITER_ANCESTORS_UP: + break; + default: + return -EINVAL; + } + + kit->start = start; + kit->pos = NULL; + kit->flags = flags; + return 0; +} + +__bpf_kfunc struct cgroup_subsys_state *bpf_iter_css_next(struct bpf_iter_css *it) +{ + struct bpf_iter_css_kern *kit = (void *)it; + + if (!kit->start) + return NULL; + + switch (kit->flags) { + case BPF_CGROUP_ITER_DESCENDANTS_PRE: + kit->pos = css_next_descendant_pre(kit->pos, kit->start); + break; + case BPF_CGROUP_ITER_DESCENDANTS_POST: + kit->pos = css_next_descendant_post(kit->pos, kit->start); + break; + case BPF_CGROUP_ITER_ANCESTORS_UP: + kit->pos = kit->pos ? kit->pos->parent : kit->start; + } + + return kit->pos; +} + +__bpf_kfunc void bpf_iter_css_destroy(struct bpf_iter_css *it) +{ +} + +__bpf_kfunc_end_defs(); diff --git a/kernel/bpf/core.c b/kernel/bpf/core.c index 5d1efe5200..fe254ae035 100644 --- a/kernel/bpf/core.c +++ b/kernel/bpf/core.c @@ -212,7 +212,7 @@ void bpf_prog_fill_jited_linfo(struct bpf_prog *prog, const struct bpf_line_info *linfo; void **jited_linfo; - if (!prog->aux->jited_linfo) + if (!prog->aux->jited_linfo || prog->aux->func_idx > prog->aux->func_cnt) /* Userspace did not provide linfo */ return; @@ -543,7 +543,7 @@ static void bpf_prog_kallsyms_del_subprogs(struct bpf_prog *fp) { int i; - for (i = 0; i < fp->aux->func_cnt; i++) + for (i = 0; i < fp->aux->real_func_cnt; i++) bpf_prog_kallsyms_del(fp->aux->func[i]); } @@ -593,7 +593,7 @@ bpf_prog_ksym_set_name(struct bpf_prog *prog) sym = bin2hex(sym, prog->tag, sizeof(prog->tag)); /* prog->aux->name will be ignored if full btf name is available */ - if (prog->aux->func_info_cnt) { + if (prog->aux->func_info_cnt && prog->aux->func_idx < prog->aux->func_info_cnt) { type = btf_type_by_id(prog->aux->btf, prog->aux->func_info[prog->aux->func_idx].type_id); func_name = btf_name_by_offset(prog->aux->btf, type->name_off); @@ -741,7 +741,7 @@ bool is_bpf_text_address(unsigned long addr) return ret; } -static struct bpf_prog *bpf_prog_ksym_find(unsigned long addr) +struct bpf_prog *bpf_prog_ksym_find(unsigned long addr) { struct bpf_ksym *ksym = bpf_ksym_find(addr); @@ -1216,7 +1216,7 @@ int bpf_jit_get_func_addr(const struct bpf_prog *prog, if (!extra_pass) addr = NULL; else if (prog->aux->func && - off >= 0 && off < prog->aux->func_cnt) + off >= 0 && off < prog->aux->real_func_cnt) addr = (u8 *)prog->aux->func[off]->bpf_func; else return -EINVAL; @@ -2729,7 +2729,7 @@ static void bpf_prog_free_deferred(struct work_struct *work) #endif if (aux->dst_trampoline) bpf_trampoline_put(aux->dst_trampoline); - for (i = 0; i < aux->func_cnt; i++) { + for (i = 0; i < aux->real_func_cnt; i++) { /* We can just unlink the subprog poke descriptor table as * it was originally linked to the main program and is also * released along with it. @@ -2737,7 +2737,7 @@ static void bpf_prog_free_deferred(struct work_struct *work) aux->func[i]->aux->poke_tab = NULL; bpf_jit_free(aux->func[i]); } - if (aux->func_cnt) { + if (aux->real_func_cnt) { kfree(aux->func); bpf_prog_unlock_free(aux->prog); } else { @@ -2922,6 +2922,15 @@ int __weak bpf_arch_text_invalidate(void *dst, size_t len) return -ENOTSUPP; } +bool __weak bpf_jit_supports_exceptions(void) +{ + return false; +} + +void __weak arch_bpf_stack_walk(bool (*consume_fn)(void *cookie, u64 ip, u64 sp, u64 bp), void *cookie) +{ +} + #ifdef CONFIG_BPF_SYSCALL static int __init bpf_global_ma_init(void) { diff --git a/kernel/bpf/cpumap.c b/kernel/bpf/cpumap.c index e42a1bdb7f..8a0bb80fe4 100644 --- a/kernel/bpf/cpumap.c +++ b/kernel/bpf/cpumap.c @@ -764,6 +764,16 @@ void __cpu_map_flush(void) } } +#ifdef CONFIG_DEBUG_NET +bool cpu_map_check_flush(void) +{ + if (list_empty(this_cpu_ptr(&cpu_map_flush_list))) + return false; + __cpu_map_flush(); + return true; +} +#endif + static int __init cpu_map_init(void) { int cpu; diff --git a/kernel/bpf/cpumask.c b/kernel/bpf/cpumask.c index 6983af8e09..e01c741e54 100644 --- a/kernel/bpf/cpumask.c +++ b/kernel/bpf/cpumask.c @@ -34,9 +34,7 @@ static bool cpu_valid(u32 cpu) return cpu < nr_cpu_ids; } -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "Global kfuncs as their definitions will be in BTF"); +__bpf_kfunc_start_defs(); /** * bpf_cpumask_create() - Create a mutable BPF cpumask. @@ -407,7 +405,7 @@ __bpf_kfunc u32 bpf_cpumask_any_and_distribute(const struct cpumask *src1, return cpumask_any_and_distribute(src1, src2); } -__diag_pop(); +__bpf_kfunc_end_defs(); BTF_SET8_START(cpumask_kfunc_btf_ids) BTF_ID_FLAGS(func, bpf_cpumask_create, KF_ACQUIRE | KF_RET_NULL) diff --git a/kernel/bpf/devmap.c b/kernel/bpf/devmap.c index 4d42f6ed6c..a936c704d4 100644 --- a/kernel/bpf/devmap.c +++ b/kernel/bpf/devmap.c @@ -418,6 +418,16 @@ void __dev_flush(void) } } +#ifdef CONFIG_DEBUG_NET +bool dev_check_flush(void) +{ + if (list_empty(this_cpu_ptr(&dev_flush_list))) + return false; + __dev_flush(); + return true; +} +#endif + /* Elements are kept alive by RCU; either by rcu_read_lock() (from syscall) or * by local_bh_disable() (from XDP calls inside NAPI). The * rcu_read_lock_bh_held() below makes lockdep accept both. diff --git a/kernel/bpf/helpers.c b/kernel/bpf/helpers.c index 607be04db7..ce4729ef1a 100644 --- a/kernel/bpf/helpers.c +++ b/kernel/bpf/helpers.c @@ -22,6 +22,7 @@ #include <linux/security.h> #include <linux/btf_ids.h> #include <linux/bpf_mem_alloc.h> +#include <linux/kasan.h> #include "../../lib/kstrtox.h" @@ -31,12 +32,13 @@ * * Different map implementations will rely on rcu in map methods * lookup/update/delete, therefore eBPF programs must run under rcu lock - * if program is allowed to access maps, so check rcu_read_lock_held in - * all three functions. + * if program is allowed to access maps, so check rcu_read_lock_held() or + * rcu_read_lock_trace_held() in all three functions. */ BPF_CALL_2(bpf_map_lookup_elem, struct bpf_map *, map, void *, key) { - WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); + WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() && + !rcu_read_lock_bh_held()); return (unsigned long) map->ops->map_lookup_elem(map, key); } @@ -52,7 +54,8 @@ const struct bpf_func_proto bpf_map_lookup_elem_proto = { BPF_CALL_4(bpf_map_update_elem, struct bpf_map *, map, void *, key, void *, value, u64, flags) { - WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); + WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() && + !rcu_read_lock_bh_held()); return map->ops->map_update_elem(map, key, value, flags); } @@ -69,7 +72,8 @@ const struct bpf_func_proto bpf_map_update_elem_proto = { BPF_CALL_2(bpf_map_delete_elem, struct bpf_map *, map, void *, key) { - WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_bh_held()); + WARN_ON_ONCE(!rcu_read_lock_held() && !rcu_read_lock_trace_held() && + !rcu_read_lock_bh_held()); return map->ops->map_delete_elem(map, key); } @@ -1097,6 +1101,7 @@ struct bpf_hrtimer { struct bpf_prog *prog; void __rcu *callback_fn; void *value; + struct rcu_head rcu; }; /* the actual struct hidden inside uapi struct bpf_timer */ @@ -1278,7 +1283,7 @@ BPF_CALL_3(bpf_timer_start, struct bpf_timer_kern *, timer, u64, nsecs, u64, fla if (in_nmi()) return -EOPNOTSUPP; - if (flags > BPF_F_TIMER_ABS) + if (flags & ~(BPF_F_TIMER_ABS | BPF_F_TIMER_CPU_PIN)) return -EINVAL; __bpf_spin_lock_irqsave(&timer->lock); t = timer->timer; @@ -1292,6 +1297,9 @@ BPF_CALL_3(bpf_timer_start, struct bpf_timer_kern *, timer, u64, nsecs, u64, fla else mode = HRTIMER_MODE_REL_SOFT; + if (flags & BPF_F_TIMER_CPU_PIN) + mode |= HRTIMER_MODE_PINNED; + hrtimer_start(&t->timer, ns_to_ktime(nsecs), mode); out: __bpf_spin_unlock_irqrestore(&timer->lock); @@ -1325,6 +1333,7 @@ BPF_CALL_1(bpf_timer_cancel, struct bpf_timer_kern *, timer) if (in_nmi()) return -EOPNOTSUPP; + rcu_read_lock(); __bpf_spin_lock_irqsave(&timer->lock); t = timer->timer; if (!t) { @@ -1346,6 +1355,7 @@ out: * if it was running. */ ret = ret ?: hrtimer_cancel(&t->timer); + rcu_read_unlock(); return ret; } @@ -1400,7 +1410,7 @@ out: */ if (this_cpu_read(hrtimer_running) != t) hrtimer_cancel(&t->timer); - kfree(t); + kfree_rcu(t, rcu); } BPF_CALL_2(bpf_kptr_xchg, void *, map_value, void *, ptr) @@ -1814,8 +1824,6 @@ bpf_base_func_proto(enum bpf_func_id func_id) } } -void __bpf_obj_drop_impl(void *p, const struct btf_record *rec); - void bpf_list_head_free(const struct btf_field *field, void *list_head, struct bpf_spin_lock *spin_lock) { @@ -1847,7 +1855,7 @@ unlock: * bpf_list_head which needs to be freed. */ migrate_disable(); - __bpf_obj_drop_impl(obj, field->graph_root.value_rec); + __bpf_obj_drop_impl(obj, field->graph_root.value_rec, false); migrate_enable(); } } @@ -1886,14 +1894,12 @@ void bpf_rb_root_free(const struct btf_field *field, void *rb_root, migrate_disable(); - __bpf_obj_drop_impl(obj, field->graph_root.value_rec); + __bpf_obj_drop_impl(obj, field->graph_root.value_rec, false); migrate_enable(); } } -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "Global functions as their definitions will be in vmlinux BTF"); +__bpf_kfunc_start_defs(); __bpf_kfunc void *bpf_obj_new_impl(u64 local_type_id__k, void *meta__ign) { @@ -1909,9 +1915,19 @@ __bpf_kfunc void *bpf_obj_new_impl(u64 local_type_id__k, void *meta__ign) return p; } +__bpf_kfunc void *bpf_percpu_obj_new_impl(u64 local_type_id__k, void *meta__ign) +{ + u64 size = local_type_id__k; + + /* The verifier has ensured that meta__ign must be NULL */ + return bpf_mem_alloc(&bpf_global_percpu_ma, size); +} + /* Must be called under migrate_disable(), as required by bpf_mem_free */ -void __bpf_obj_drop_impl(void *p, const struct btf_record *rec) +void __bpf_obj_drop_impl(void *p, const struct btf_record *rec, bool percpu) { + struct bpf_mem_alloc *ma; + if (rec && rec->refcount_off >= 0 && !refcount_dec_and_test((refcount_t *)(p + rec->refcount_off))) { /* Object is refcounted and refcount_dec didn't result in 0 @@ -1923,10 +1939,14 @@ void __bpf_obj_drop_impl(void *p, const struct btf_record *rec) if (rec) bpf_obj_free_fields(rec, p); + if (percpu) + ma = &bpf_global_percpu_ma; + else + ma = &bpf_global_ma; if (rec && rec->refcount_off >= 0) - bpf_mem_free_rcu(&bpf_global_ma, p); + bpf_mem_free_rcu(ma, p); else - bpf_mem_free(&bpf_global_ma, p); + bpf_mem_free(ma, p); } __bpf_kfunc void bpf_obj_drop_impl(void *p__alloc, void *meta__ign) @@ -1934,7 +1954,13 @@ __bpf_kfunc void bpf_obj_drop_impl(void *p__alloc, void *meta__ign) struct btf_struct_meta *meta = meta__ign; void *p = p__alloc; - __bpf_obj_drop_impl(p, meta ? meta->record : NULL); + __bpf_obj_drop_impl(p, meta ? meta->record : NULL, false); +} + +__bpf_kfunc void bpf_percpu_obj_drop_impl(void *p__alloc, void *meta__ign) +{ + /* The verifier has ensured that meta__ign must be NULL */ + bpf_mem_free_rcu(&bpf_global_percpu_ma, p__alloc); } __bpf_kfunc void *bpf_refcount_acquire_impl(void *p__refcounted_kptr, void *meta__ign) @@ -1972,7 +1998,7 @@ static int __bpf_list_add(struct bpf_list_node_kern *node, */ if (cmpxchg(&node->owner, NULL, BPF_PTR_POISON)) { /* Only called from BPF prog, no need to migrate_disable */ - __bpf_obj_drop_impl((void *)n - off, rec); + __bpf_obj_drop_impl((void *)n - off, rec, false); return -EINVAL; } @@ -2071,7 +2097,7 @@ static int __bpf_rbtree_add(struct bpf_rb_root *root, */ if (cmpxchg(&node->owner, NULL, BPF_PTR_POISON)) { /* Only called from BPF prog, no need to migrate_disable */ - __bpf_obj_drop_impl((void *)n - off, rec); + __bpf_obj_drop_impl((void *)n - off, rec, false); return -EINVAL; } @@ -2447,15 +2473,60 @@ __bpf_kfunc void bpf_rcu_read_unlock(void) rcu_read_unlock(); } -__diag_pop(); +struct bpf_throw_ctx { + struct bpf_prog_aux *aux; + u64 sp; + u64 bp; + int cnt; +}; + +static bool bpf_stack_walker(void *cookie, u64 ip, u64 sp, u64 bp) +{ + struct bpf_throw_ctx *ctx = cookie; + struct bpf_prog *prog; + + if (!is_bpf_text_address(ip)) + return !ctx->cnt; + prog = bpf_prog_ksym_find(ip); + ctx->cnt++; + if (bpf_is_subprog(prog)) + return true; + ctx->aux = prog->aux; + ctx->sp = sp; + ctx->bp = bp; + return false; +} + +__bpf_kfunc void bpf_throw(u64 cookie) +{ + struct bpf_throw_ctx ctx = {}; + + arch_bpf_stack_walk(bpf_stack_walker, &ctx); + WARN_ON_ONCE(!ctx.aux); + if (ctx.aux) + WARN_ON_ONCE(!ctx.aux->exception_boundary); + WARN_ON_ONCE(!ctx.bp); + WARN_ON_ONCE(!ctx.cnt); + /* Prevent KASAN false positives for CONFIG_KASAN_STACK by unpoisoning + * deeper stack depths than ctx.sp as we do not return from bpf_throw, + * which skips compiler generated instrumentation to do the same. + */ + kasan_unpoison_task_stack_below((void *)(long)ctx.sp); + ctx.aux->bpf_exception_cb(cookie, ctx.sp, ctx.bp, 0, 0); + WARN(1, "A call to BPF exception callback should never return\n"); +} + +__bpf_kfunc_end_defs(); BTF_SET8_START(generic_btf_ids) #ifdef CONFIG_KEXEC_CORE BTF_ID_FLAGS(func, crash_kexec, KF_DESTRUCTIVE) #endif BTF_ID_FLAGS(func, bpf_obj_new_impl, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_percpu_obj_new_impl, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_obj_drop_impl, KF_RELEASE) -BTF_ID_FLAGS(func, bpf_refcount_acquire_impl, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_percpu_obj_drop_impl, KF_RELEASE) +BTF_ID_FLAGS(func, bpf_refcount_acquire_impl, KF_ACQUIRE | KF_RET_NULL | KF_RCU) BTF_ID_FLAGS(func, bpf_list_push_front_impl) BTF_ID_FLAGS(func, bpf_list_push_back_impl) BTF_ID_FLAGS(func, bpf_list_pop_front, KF_ACQUIRE | KF_RET_NULL) @@ -2474,6 +2545,7 @@ BTF_ID_FLAGS(func, bpf_cgroup_from_id, KF_ACQUIRE | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_task_under_cgroup, KF_RCU) #endif BTF_ID_FLAGS(func, bpf_task_from_pid, KF_ACQUIRE | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_throw) BTF_SET8_END(generic_btf_ids) static const struct btf_kfunc_id_set generic_kfunc_set = { @@ -2500,6 +2572,20 @@ BTF_ID_FLAGS(func, bpf_dynptr_slice_rdwr, KF_RET_NULL) BTF_ID_FLAGS(func, bpf_iter_num_new, KF_ITER_NEW) BTF_ID_FLAGS(func, bpf_iter_num_next, KF_ITER_NEXT | KF_RET_NULL) BTF_ID_FLAGS(func, bpf_iter_num_destroy, KF_ITER_DESTROY) +BTF_ID_FLAGS(func, bpf_iter_task_vma_new, KF_ITER_NEW | KF_RCU) +BTF_ID_FLAGS(func, bpf_iter_task_vma_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_task_vma_destroy, KF_ITER_DESTROY) +#ifdef CONFIG_CGROUPS +BTF_ID_FLAGS(func, bpf_iter_css_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS) +BTF_ID_FLAGS(func, bpf_iter_css_task_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_css_task_destroy, KF_ITER_DESTROY) +BTF_ID_FLAGS(func, bpf_iter_css_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED) +BTF_ID_FLAGS(func, bpf_iter_css_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_css_destroy, KF_ITER_DESTROY) +#endif +BTF_ID_FLAGS(func, bpf_iter_task_new, KF_ITER_NEW | KF_TRUSTED_ARGS | KF_RCU_PROTECTED) +BTF_ID_FLAGS(func, bpf_iter_task_next, KF_ITER_NEXT | KF_RET_NULL) +BTF_ID_FLAGS(func, bpf_iter_task_destroy, KF_ITER_DESTROY) BTF_ID_FLAGS(func, bpf_dynptr_adjust) BTF_ID_FLAGS(func, bpf_dynptr_is_null) BTF_ID_FLAGS(func, bpf_dynptr_is_rdonly) diff --git a/kernel/bpf/inode.c b/kernel/bpf/inode.c index 99d0625b6c..1aafb2ff2e 100644 --- a/kernel/bpf/inode.c +++ b/kernel/bpf/inode.c @@ -118,8 +118,7 @@ static struct inode *bpf_get_inode(struct super_block *sb, return ERR_PTR(-ENOSPC); inode->i_ino = get_next_ino(); - inode->i_atime = inode_set_ctime_current(inode); - inode->i_mtime = inode->i_atime; + simple_inode_init_ts(inode); inode_init_owner(&nop_mnt_idmap, inode, dir, mode); @@ -147,7 +146,7 @@ static void bpf_dentry_finalize(struct dentry *dentry, struct inode *inode, d_instantiate(dentry, inode); dget(dentry); - dir->i_mtime = inode_set_ctime_current(dir); + inode_set_mtime_to_ts(dir, inode_set_ctime_current(dir)); } static int bpf_mkdir(struct mnt_idmap *idmap, struct inode *dir, diff --git a/kernel/bpf/map_iter.c b/kernel/bpf/map_iter.c index 6fc9dae9ed..6abd7c5df4 100644 --- a/kernel/bpf/map_iter.c +++ b/kernel/bpf/map_iter.c @@ -193,9 +193,7 @@ static int __init bpf_map_iter_init(void) late_initcall(bpf_map_iter_init); -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "Global functions as their definitions will be in vmlinux BTF"); +__bpf_kfunc_start_defs(); __bpf_kfunc s64 bpf_map_sum_elem_count(const struct bpf_map *map) { @@ -213,7 +211,7 @@ __bpf_kfunc s64 bpf_map_sum_elem_count(const struct bpf_map *map) return ret; } -__diag_pop(); +__bpf_kfunc_end_defs(); BTF_SET8_START(bpf_map_iter_kfunc_ids) BTF_ID_FLAGS(func, bpf_map_sum_elem_count, KF_TRUSTED_ARGS) diff --git a/kernel/bpf/memalloc.c b/kernel/bpf/memalloc.c index 85f9501ff6..aa0fbf000a 100644 --- a/kernel/bpf/memalloc.c +++ b/kernel/bpf/memalloc.c @@ -340,6 +340,7 @@ static void free_bulk(struct bpf_mem_cache *c) int cnt; WARN_ON_ONCE(tgt->unit_size != c->unit_size); + WARN_ON_ONCE(tgt->percpu_size != c->percpu_size); do { inc_active(c, &flags); @@ -365,6 +366,9 @@ static void __free_by_rcu(struct rcu_head *head) struct bpf_mem_cache *tgt = c->tgt; struct llist_node *llnode; + WARN_ON_ONCE(tgt->unit_size != c->unit_size); + WARN_ON_ONCE(tgt->percpu_size != c->percpu_size); + llnode = llist_del_all(&c->waiting_for_gp); if (!llnode) goto out; @@ -501,6 +505,9 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) struct obj_cgroup *objcg = NULL; int cpu, i, unit_size, percpu_size = 0; + /* room for llist_node and per-cpu pointer */ + if (percpu) + percpu_size = LLIST_NODE_SZ + sizeof(void *); ma->percpu = percpu; if (size) { @@ -508,10 +515,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) if (!pc) return -ENOMEM; - if (percpu) - /* room for llist_node and per-cpu pointer */ - percpu_size = LLIST_NODE_SZ + sizeof(void *); - else + if (!percpu) size += LLIST_NODE_SZ; /* room for llist_node */ unit_size = size; @@ -532,10 +536,6 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) return 0; } - /* size == 0 && percpu is an invalid combination */ - if (WARN_ON_ONCE(percpu)) - return -EINVAL; - pcc = __alloc_percpu_gfp(sizeof(*cc), 8, GFP_KERNEL); if (!pcc) return -ENOMEM; @@ -548,6 +548,7 @@ int bpf_mem_alloc_init(struct bpf_mem_alloc *ma, int size, bool percpu) c = &cc->cache[i]; c->unit_size = sizes[i]; c->objcg = objcg; + c->percpu_size = percpu_size; c->tgt = c; init_refill_work(c); @@ -742,12 +743,17 @@ static void notrace *unit_alloc(struct bpf_mem_cache *c) } } local_dec(&c->active); - local_irq_restore(flags); WARN_ON(cnt < 0); if (cnt < c->low_watermark) irq_work_raise(c); + /* Enable IRQ after the enqueue of irq work completes, so irq work + * will run after IRQ is enabled and free_llist may be refilled by + * irq work before other task preempts current task. + */ + local_irq_restore(flags); + return llnode; } @@ -783,11 +789,16 @@ static void notrace unit_free(struct bpf_mem_cache *c, void *ptr) llist_add(llnode, &c->free_llist_extra); } local_dec(&c->active); - local_irq_restore(flags); if (cnt > c->high_watermark) /* free few objects from current cpu into global kmalloc pool */ irq_work_raise(c); + /* Enable IRQ after irq_work_raise() completes, otherwise when current + * task is preempted by task which does unit_alloc(), unit_alloc() may + * return NULL unexpectedly because irq work is already pending but can + * not been triggered and free_llist can not be refilled timely. + */ + local_irq_restore(flags); } static void notrace unit_free_rcu(struct bpf_mem_cache *c, void *ptr) @@ -805,10 +816,10 @@ static void notrace unit_free_rcu(struct bpf_mem_cache *c, void *ptr) llist_add(llnode, &c->free_llist_extra_rcu); } local_dec(&c->active); - local_irq_restore(flags); if (!atomic_read(&c->call_rcu_in_progress)) irq_work_raise(c); + local_irq_restore(flags); } /* Called from BPF program or from sys_bpf syscall. diff --git a/kernel/bpf/offload.c b/kernel/bpf/offload.c index 87d6693d82..1a4fec330e 100644 --- a/kernel/bpf/offload.c +++ b/kernel/bpf/offload.c @@ -234,7 +234,14 @@ int bpf_prog_dev_bound_init(struct bpf_prog *prog, union bpf_attr *attr) attr->prog_type != BPF_PROG_TYPE_XDP) return -EINVAL; - if (attr->prog_flags & ~BPF_F_XDP_DEV_BOUND_ONLY) + if (attr->prog_flags & ~(BPF_F_XDP_DEV_BOUND_ONLY | BPF_F_XDP_HAS_FRAGS)) + return -EINVAL; + + /* Frags are allowed only if program is dev-bound-only, but not + * if it is requesting bpf offload. + */ + if (attr->prog_flags & BPF_F_XDP_HAS_FRAGS && + !(attr->prog_flags & BPF_F_XDP_DEV_BOUND_ONLY)) return -EINVAL; if (attr->prog_type == BPF_PROG_TYPE_SCHED_CLS && @@ -847,10 +854,11 @@ void *bpf_dev_bound_resolve_kfunc(struct bpf_prog *prog, u32 func_id) if (!ops) goto out; - if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_TIMESTAMP)) - p = ops->xmo_rx_timestamp; - else if (func_id == bpf_xdp_metadata_kfunc_id(XDP_METADATA_KFUNC_RX_HASH)) - p = ops->xmo_rx_hash; +#define XDP_METADATA_KFUNC(name, _, __, xmo) \ + if (func_id == bpf_xdp_metadata_kfunc_id(name)) p = ops->xmo; + XDP_METADATA_KFUNC_xxx +#undef XDP_METADATA_KFUNC + out: up_read(&bpf_devs_lock); diff --git a/kernel/bpf/ringbuf.c b/kernel/bpf/ringbuf.c index f045fde632..0ee653a936 100644 --- a/kernel/bpf/ringbuf.c +++ b/kernel/bpf/ringbuf.c @@ -770,8 +770,7 @@ schedule_work_return: /* Prevent the clearing of the busy-bit from being reordered before the * storing of any rb consumer or producer positions. */ - smp_mb__before_atomic(); - atomic_set(&rb->busy, 0); + atomic_set_release(&rb->busy, 0); if (flags & BPF_RB_FORCE_WAKEUP) irq_work_queue(&rb->work); diff --git a/kernel/bpf/stackmap.c b/kernel/bpf/stackmap.c index 36775c4bc3..dff7ba5397 100644 --- a/kernel/bpf/stackmap.c +++ b/kernel/bpf/stackmap.c @@ -28,7 +28,7 @@ struct bpf_stack_map { void *elems; struct pcpu_freelist freelist; u32 n_buckets; - struct stack_map_bucket *buckets[]; + struct stack_map_bucket *buckets[] __counted_by(n_buckets); }; static inline bool stack_map_use_build_id(struct bpf_map *map) diff --git a/kernel/bpf/syscall.c b/kernel/bpf/syscall.c index f61c53237c..349d735b4e 100644 --- a/kernel/bpf/syscall.c +++ b/kernel/bpf/syscall.c @@ -35,8 +35,9 @@ #include <linux/rcupdate_trace.h> #include <linux/memcontrol.h> #include <linux/trace_events.h> -#include <net/netfilter/nf_bpf_link.h> +#include <net/netfilter/nf_bpf_link.h> +#include <net/netkit.h> #include <net/tcx.h> #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \ @@ -514,6 +515,7 @@ void btf_record_free(struct btf_record *rec) switch (rec->fields[i].type) { case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: if (rec->fields[i].kptr.module) module_put(rec->fields[i].kptr.module); btf_put(rec->fields[i].kptr.btf); @@ -560,6 +562,7 @@ struct btf_record *btf_record_dup(const struct btf_record *rec) switch (fields[i].type) { case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: btf_get(fields[i].kptr.btf); if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) { ret = -ENXIO; @@ -624,8 +627,6 @@ void bpf_obj_free_timer(const struct btf_record *rec, void *obj) bpf_timer_cancel_and_free(obj + rec->timer_off); } -extern void __bpf_obj_drop_impl(void *p, const struct btf_record *rec); - void bpf_obj_free_fields(const struct btf_record *rec, void *obj) { const struct btf_field *fields; @@ -650,6 +651,7 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj) WRITE_ONCE(*(u64 *)field_ptr, 0); break; case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0); if (!xchgd_field) break; @@ -659,8 +661,8 @@ void bpf_obj_free_fields(const struct btf_record *rec, void *obj) field->kptr.btf_id); migrate_disable(); __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ? - pointee_struct_meta->record : - NULL); + pointee_struct_meta->record : NULL, + fields[i].type == BPF_KPTR_PERCPU); migrate_enable(); } else { field->kptr.dtor(xchgd_field); @@ -1071,6 +1073,7 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf, break; case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: case BPF_REFCOUNT: if (map->map_type != BPF_MAP_TYPE_HASH && map->map_type != BPF_MAP_TYPE_PERCPU_HASH && @@ -1699,6 +1702,9 @@ int generic_map_delete_batch(struct bpf_map *map, if (!max_count) return 0; + if (put_user(0, &uattr->batch.count)) + return -EFAULT; + key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); if (!key) return -ENOMEM; @@ -1756,6 +1762,9 @@ int generic_map_update_batch(struct bpf_map *map, struct file *map_file, if (!max_count) return 0; + if (put_user(0, &uattr->batch.count)) + return -EFAULT; + key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN); if (!key) return -ENOMEM; @@ -2468,14 +2477,19 @@ bpf_prog_load_check_attach(enum bpf_prog_type prog_type, case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_UNIX_CONNECT: case BPF_CGROUP_INET4_GETPEERNAME: case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_UNIX_GETPEERNAME: case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_INET6_GETSOCKNAME: + case BPF_CGROUP_UNIX_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: + case BPF_CGROUP_UNIX_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UNIX_RECVMSG: return 0; default: return -EINVAL; @@ -2771,7 +2785,7 @@ free_used_maps: * period before we can tear down JIT memory since symbols * are already exposed under kallsyms. */ - __bpf_prog_put_noref(prog, prog->aux->func_cnt); + __bpf_prog_put_noref(prog, prog->aux->real_func_cnt); return err; free_prog_sec: free_uid(prog->aux->user); @@ -3405,7 +3419,7 @@ static void bpf_perf_link_dealloc(struct bpf_link *link) static int bpf_perf_link_fill_common(const struct perf_event *event, char __user *uname, u32 ulen, u64 *probe_offset, u64 *probe_addr, - u32 *fd_type) + u32 *fd_type, unsigned long *missed) { const char *buf; u32 prog_id; @@ -3416,7 +3430,7 @@ static int bpf_perf_link_fill_common(const struct perf_event *event, return -EINVAL; err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf, - probe_offset, probe_addr); + probe_offset, probe_addr, missed); if (err) return err; if (!uname) @@ -3439,6 +3453,7 @@ static int bpf_perf_link_fill_common(const struct perf_event *event, static int bpf_perf_link_fill_kprobe(const struct perf_event *event, struct bpf_link_info *info) { + unsigned long missed; char __user *uname; u64 addr, offset; u32 ulen, type; @@ -3447,7 +3462,7 @@ static int bpf_perf_link_fill_kprobe(const struct perf_event *event, uname = u64_to_user_ptr(info->perf_event.kprobe.func_name); ulen = info->perf_event.kprobe.name_len; err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, - &type); + &type, &missed); if (err) return err; if (type == BPF_FD_TYPE_KRETPROBE) @@ -3456,6 +3471,7 @@ static int bpf_perf_link_fill_kprobe(const struct perf_event *event, info->perf_event.type = BPF_PERF_EVENT_KPROBE; info->perf_event.kprobe.offset = offset; + info->perf_event.kprobe.missed = missed; if (!kallsyms_show_value(current_cred())) addr = 0; info->perf_event.kprobe.addr = addr; @@ -3475,7 +3491,7 @@ static int bpf_perf_link_fill_uprobe(const struct perf_event *event, uname = u64_to_user_ptr(info->perf_event.uprobe.file_name); ulen = info->perf_event.uprobe.name_len; err = bpf_perf_link_fill_common(event, uname, ulen, &offset, &addr, - &type); + &type, NULL); if (err) return err; @@ -3511,7 +3527,7 @@ static int bpf_perf_link_fill_tracepoint(const struct perf_event *event, uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name); ulen = info->perf_event.tracepoint.name_len; info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT; - return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL); + return bpf_perf_link_fill_common(event, uname, ulen, NULL, NULL, NULL, NULL); } static int bpf_perf_link_fill_perf_event(const struct perf_event *event, @@ -3707,14 +3723,19 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type) case BPF_CGROUP_INET6_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_UNIX_CONNECT: case BPF_CGROUP_INET4_GETPEERNAME: case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_UNIX_GETPEERNAME: case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_INET6_GETSOCKNAME: + case BPF_CGROUP_UNIX_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: + case BPF_CGROUP_UNIX_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UNIX_RECVMSG: return BPF_PROG_TYPE_CGROUP_SOCK_ADDR; case BPF_CGROUP_SOCK_OPS: return BPF_PROG_TYPE_SOCK_OPS; @@ -3751,6 +3772,8 @@ attach_type_to_prog_type(enum bpf_attach_type attach_type) return BPF_PROG_TYPE_LSM; case BPF_TCX_INGRESS: case BPF_TCX_EGRESS: + case BPF_NETKIT_PRIMARY: + case BPF_NETKIT_PEER: return BPF_PROG_TYPE_SCHED_CLS; default: return BPF_PROG_TYPE_UNSPEC; @@ -3802,7 +3825,9 @@ static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog, return 0; case BPF_PROG_TYPE_SCHED_CLS: if (attach_type != BPF_TCX_INGRESS && - attach_type != BPF_TCX_EGRESS) + attach_type != BPF_TCX_EGRESS && + attach_type != BPF_NETKIT_PRIMARY && + attach_type != BPF_NETKIT_PEER) return -EINVAL; return 0; default: @@ -3885,7 +3910,11 @@ static int bpf_prog_attach(const union bpf_attr *attr) ret = cgroup_bpf_prog_attach(attr, ptype, prog); break; case BPF_PROG_TYPE_SCHED_CLS: - ret = tcx_prog_attach(attr, prog); + if (attr->attach_type == BPF_TCX_INGRESS || + attr->attach_type == BPF_TCX_EGRESS) + ret = tcx_prog_attach(attr, prog); + else + ret = netkit_prog_attach(attr, prog); break; default: ret = -EINVAL; @@ -3946,7 +3975,11 @@ static int bpf_prog_detach(const union bpf_attr *attr) ret = cgroup_bpf_prog_detach(attr, ptype); break; case BPF_PROG_TYPE_SCHED_CLS: - ret = tcx_prog_detach(attr, prog); + if (attr->attach_type == BPF_TCX_INGRESS || + attr->attach_type == BPF_TCX_EGRESS) + ret = tcx_prog_detach(attr, prog); + else + ret = netkit_prog_detach(attr, prog); break; default: ret = -EINVAL; @@ -3980,14 +4013,19 @@ static int bpf_prog_query(const union bpf_attr *attr, case BPF_CGROUP_INET6_POST_BIND: case BPF_CGROUP_INET4_CONNECT: case BPF_CGROUP_INET6_CONNECT: + case BPF_CGROUP_UNIX_CONNECT: case BPF_CGROUP_INET4_GETPEERNAME: case BPF_CGROUP_INET6_GETPEERNAME: + case BPF_CGROUP_UNIX_GETPEERNAME: case BPF_CGROUP_INET4_GETSOCKNAME: case BPF_CGROUP_INET6_GETSOCKNAME: + case BPF_CGROUP_UNIX_GETSOCKNAME: case BPF_CGROUP_UDP4_SENDMSG: case BPF_CGROUP_UDP6_SENDMSG: + case BPF_CGROUP_UNIX_SENDMSG: case BPF_CGROUP_UDP4_RECVMSG: case BPF_CGROUP_UDP6_RECVMSG: + case BPF_CGROUP_UNIX_RECVMSG: case BPF_CGROUP_SOCK_OPS: case BPF_CGROUP_DEVICE: case BPF_CGROUP_SYSCTL: @@ -4008,6 +4046,9 @@ static int bpf_prog_query(const union bpf_attr *attr, case BPF_TCX_INGRESS: case BPF_TCX_EGRESS: return tcx_prog_query(attr, uattr); + case BPF_NETKIT_PRIMARY: + case BPF_NETKIT_PEER: + return netkit_prog_query(attr, uattr); default: return -EINVAL; } @@ -4853,7 +4894,7 @@ static int bpf_task_fd_query(const union bpf_attr *attr, err = bpf_get_perf_event_info(event, &prog_id, &fd_type, &buf, &probe_offset, - &probe_addr); + &probe_addr, NULL); if (!err) err = bpf_task_fd_query_copy(attr, uattr, prog_id, fd_type, buf, @@ -4989,7 +5030,11 @@ static int link_create(union bpf_attr *attr, bpfptr_t uattr) ret = bpf_xdp_link_attach(attr, prog); break; case BPF_PROG_TYPE_SCHED_CLS: - ret = tcx_link_attach(attr, prog); + if (attr->link_create.attach_type == BPF_TCX_INGRESS || + attr->link_create.attach_type == BPF_TCX_EGRESS) + ret = tcx_link_attach(attr, prog); + else + ret = netkit_link_attach(attr, prog); break; case BPF_PROG_TYPE_NETFILTER: ret = bpf_nf_link_attach(attr, prog); diff --git a/kernel/bpf/task_iter.c b/kernel/bpf/task_iter.c index c4ab9d6cdb..26082b9789 100644 --- a/kernel/bpf/task_iter.c +++ b/kernel/bpf/task_iter.c @@ -7,7 +7,9 @@ #include <linux/fs.h> #include <linux/fdtable.h> #include <linux/filter.h> +#include <linux/bpf_mem_alloc.h> #include <linux/btf_ids.h> +#include <linux/mm_types.h> #include "mmap_unlock_work.h" static const char * const iter_task_type_names[] = { @@ -35,16 +37,13 @@ static struct task_struct *task_group_seq_get_next(struct bpf_iter_seq_task_comm u32 *tid, bool skip_if_dup_files) { - struct task_struct *task, *next_task; + struct task_struct *task; struct pid *pid; - u32 saved_tid; + u32 next_tid; if (!*tid) { /* The first time, the iterator calls this function. */ pid = find_pid_ns(common->pid, common->ns); - if (!pid) - return NULL; - task = get_pid_task(pid, PIDTYPE_TGID); if (!task) return NULL; @@ -66,44 +65,27 @@ static struct task_struct *task_group_seq_get_next(struct bpf_iter_seq_task_comm return task; } - pid = find_pid_ns(common->pid_visiting, common->ns); - if (!pid) - return NULL; - - task = get_pid_task(pid, PIDTYPE_PID); + task = find_task_by_pid_ns(common->pid_visiting, common->ns); if (!task) return NULL; retry: - if (!pid_alive(task)) { - put_task_struct(task); - return NULL; - } + task = next_thread(task); - next_task = next_thread(task); - put_task_struct(task); - if (!next_task) - return NULL; - - saved_tid = *tid; - *tid = __task_pid_nr_ns(next_task, PIDTYPE_PID, common->ns); - if (!*tid || *tid == common->pid) { + next_tid = __task_pid_nr_ns(task, PIDTYPE_PID, common->ns); + if (!next_tid || next_tid == common->pid) { /* Run out of tasks of a process. The tasks of a * thread_group are linked as circular linked list. */ - *tid = saved_tid; return NULL; } - get_task_struct(next_task); - common->pid_visiting = *tid; - - if (skip_if_dup_files && task->files == task->group_leader->files) { - task = next_task; + if (skip_if_dup_files && task->files == task->group_leader->files) goto retry; - } - return next_task; + *tid = common->pid_visiting = next_tid; + get_task_struct(task); + return task; } static struct task_struct *task_seq_get_next(struct bpf_iter_seq_task_common *common, @@ -308,11 +290,9 @@ again: rcu_read_lock(); for (;; curr_fd++) { struct file *f; - f = task_lookup_next_fd_rcu(curr_task, &curr_fd); + f = task_lookup_next_fdget_rcu(curr_task, &curr_fd); if (!f) break; - if (!get_file_rcu(f)) - continue; /* set info->fd */ info->fd = curr_fd; @@ -724,7 +704,7 @@ static struct bpf_iter_reg task_reg_info = { .ctx_arg_info_size = 1, .ctx_arg_info = { { offsetof(struct bpf_iter__task, task), - PTR_TO_BTF_ID_OR_NULL }, + PTR_TO_BTF_ID_OR_NULL | PTR_TRUSTED }, }, .seq_info = &task_seq_info, .fill_link_info = bpf_iter_fill_link_info, @@ -823,6 +803,244 @@ const struct bpf_func_proto bpf_find_vma_proto = { .arg5_type = ARG_ANYTHING, }; +struct bpf_iter_task_vma_kern_data { + struct task_struct *task; + struct mm_struct *mm; + struct mmap_unlock_irq_work *work; + struct vma_iterator vmi; +}; + +struct bpf_iter_task_vma { + /* opaque iterator state; having __u64 here allows to preserve correct + * alignment requirements in vmlinux.h, generated from BTF + */ + __u64 __opaque[1]; +} __attribute__((aligned(8))); + +/* Non-opaque version of bpf_iter_task_vma */ +struct bpf_iter_task_vma_kern { + struct bpf_iter_task_vma_kern_data *data; +} __attribute__((aligned(8))); + +__bpf_kfunc_start_defs(); + +__bpf_kfunc int bpf_iter_task_vma_new(struct bpf_iter_task_vma *it, + struct task_struct *task, u64 addr) +{ + struct bpf_iter_task_vma_kern *kit = (void *)it; + bool irq_work_busy = false; + int err; + + BUILD_BUG_ON(sizeof(struct bpf_iter_task_vma_kern) != sizeof(struct bpf_iter_task_vma)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_task_vma_kern) != __alignof__(struct bpf_iter_task_vma)); + + /* is_iter_reg_valid_uninit guarantees that kit hasn't been initialized + * before, so non-NULL kit->data doesn't point to previously + * bpf_mem_alloc'd bpf_iter_task_vma_kern_data + */ + kit->data = bpf_mem_alloc(&bpf_global_ma, sizeof(struct bpf_iter_task_vma_kern_data)); + if (!kit->data) + return -ENOMEM; + + kit->data->task = get_task_struct(task); + kit->data->mm = task->mm; + if (!kit->data->mm) { + err = -ENOENT; + goto err_cleanup_iter; + } + + /* kit->data->work == NULL is valid after bpf_mmap_unlock_get_irq_work */ + irq_work_busy = bpf_mmap_unlock_get_irq_work(&kit->data->work); + if (irq_work_busy || !mmap_read_trylock(kit->data->mm)) { + err = -EBUSY; + goto err_cleanup_iter; + } + + vma_iter_init(&kit->data->vmi, kit->data->mm, addr); + return 0; + +err_cleanup_iter: + if (kit->data->task) + put_task_struct(kit->data->task); + bpf_mem_free(&bpf_global_ma, kit->data); + /* NULL kit->data signals failed bpf_iter_task_vma initialization */ + kit->data = NULL; + return err; +} + +__bpf_kfunc struct vm_area_struct *bpf_iter_task_vma_next(struct bpf_iter_task_vma *it) +{ + struct bpf_iter_task_vma_kern *kit = (void *)it; + + if (!kit->data) /* bpf_iter_task_vma_new failed */ + return NULL; + return vma_next(&kit->data->vmi); +} + +__bpf_kfunc void bpf_iter_task_vma_destroy(struct bpf_iter_task_vma *it) +{ + struct bpf_iter_task_vma_kern *kit = (void *)it; + + if (kit->data) { + bpf_mmap_unlock_mm(kit->data->work, kit->data->mm); + put_task_struct(kit->data->task); + bpf_mem_free(&bpf_global_ma, kit->data); + } +} + +__bpf_kfunc_end_defs(); + +#ifdef CONFIG_CGROUPS + +struct bpf_iter_css_task { + __u64 __opaque[1]; +} __attribute__((aligned(8))); + +struct bpf_iter_css_task_kern { + struct css_task_iter *css_it; +} __attribute__((aligned(8))); + +__bpf_kfunc_start_defs(); + +__bpf_kfunc int bpf_iter_css_task_new(struct bpf_iter_css_task *it, + struct cgroup_subsys_state *css, unsigned int flags) +{ + struct bpf_iter_css_task_kern *kit = (void *)it; + + BUILD_BUG_ON(sizeof(struct bpf_iter_css_task_kern) != sizeof(struct bpf_iter_css_task)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_css_task_kern) != + __alignof__(struct bpf_iter_css_task)); + kit->css_it = NULL; + switch (flags) { + case CSS_TASK_ITER_PROCS | CSS_TASK_ITER_THREADED: + case CSS_TASK_ITER_PROCS: + case 0: + break; + default: + return -EINVAL; + } + + kit->css_it = bpf_mem_alloc(&bpf_global_ma, sizeof(struct css_task_iter)); + if (!kit->css_it) + return -ENOMEM; + css_task_iter_start(css, flags, kit->css_it); + return 0; +} + +__bpf_kfunc struct task_struct *bpf_iter_css_task_next(struct bpf_iter_css_task *it) +{ + struct bpf_iter_css_task_kern *kit = (void *)it; + + if (!kit->css_it) + return NULL; + return css_task_iter_next(kit->css_it); +} + +__bpf_kfunc void bpf_iter_css_task_destroy(struct bpf_iter_css_task *it) +{ + struct bpf_iter_css_task_kern *kit = (void *)it; + + if (!kit->css_it) + return; + css_task_iter_end(kit->css_it); + bpf_mem_free(&bpf_global_ma, kit->css_it); +} + +__bpf_kfunc_end_defs(); + +#endif /* CONFIG_CGROUPS */ + +struct bpf_iter_task { + __u64 __opaque[3]; +} __attribute__((aligned(8))); + +struct bpf_iter_task_kern { + struct task_struct *task; + struct task_struct *pos; + unsigned int flags; +} __attribute__((aligned(8))); + +enum { + /* all process in the system */ + BPF_TASK_ITER_ALL_PROCS, + /* all threads in the system */ + BPF_TASK_ITER_ALL_THREADS, + /* all threads of a specific process */ + BPF_TASK_ITER_PROC_THREADS +}; + +__bpf_kfunc_start_defs(); + +__bpf_kfunc int bpf_iter_task_new(struct bpf_iter_task *it, + struct task_struct *task__nullable, unsigned int flags) +{ + struct bpf_iter_task_kern *kit = (void *)it; + + BUILD_BUG_ON(sizeof(struct bpf_iter_task_kern) > sizeof(struct bpf_iter_task)); + BUILD_BUG_ON(__alignof__(struct bpf_iter_task_kern) != + __alignof__(struct bpf_iter_task)); + + kit->task = kit->pos = NULL; + switch (flags) { + case BPF_TASK_ITER_ALL_THREADS: + case BPF_TASK_ITER_ALL_PROCS: + break; + case BPF_TASK_ITER_PROC_THREADS: + if (!task__nullable) + return -EINVAL; + break; + default: + return -EINVAL; + } + + if (flags == BPF_TASK_ITER_PROC_THREADS) + kit->task = task__nullable; + else + kit->task = &init_task; + kit->pos = kit->task; + kit->flags = flags; + return 0; +} + +__bpf_kfunc struct task_struct *bpf_iter_task_next(struct bpf_iter_task *it) +{ + struct bpf_iter_task_kern *kit = (void *)it; + struct task_struct *pos; + unsigned int flags; + + flags = kit->flags; + pos = kit->pos; + + if (!pos) + return pos; + + if (flags == BPF_TASK_ITER_ALL_PROCS) + goto get_next_task; + + kit->pos = next_thread(kit->pos); + if (kit->pos == kit->task) { + if (flags == BPF_TASK_ITER_PROC_THREADS) { + kit->pos = NULL; + return pos; + } + } else + return pos; + +get_next_task: + kit->pos = next_task(kit->pos); + kit->task = kit->pos; + if (kit->pos == &init_task) + kit->pos = NULL; + + return pos; +} + +__bpf_kfunc void bpf_iter_task_destroy(struct bpf_iter_task *it) +{ +} + +__bpf_kfunc_end_defs(); + DEFINE_PER_CPU(struct mmap_unlock_irq_work, mmap_unlock_work); static void do_mmap_read_unlock(struct irq_work *entry) diff --git a/kernel/bpf/tcx.c b/kernel/bpf/tcx.c index 1338a13a8b..2e4885e778 100644 --- a/kernel/bpf/tcx.c +++ b/kernel/bpf/tcx.c @@ -250,7 +250,7 @@ static void tcx_link_dealloc(struct bpf_link *link) static void tcx_link_fdinfo(const struct bpf_link *link, struct seq_file *seq) { - const struct tcx_link *tcx = tcx_link_const(link); + const struct tcx_link *tcx = tcx_link(link); u32 ifindex = 0; rtnl_lock(); @@ -267,7 +267,7 @@ static void tcx_link_fdinfo(const struct bpf_link *link, struct seq_file *seq) static int tcx_link_fill_info(const struct bpf_link *link, struct bpf_link_info *info) { - const struct tcx_link *tcx = tcx_link_const(link); + const struct tcx_link *tcx = tcx_link(link); u32 ifindex = 0; rtnl_lock(); diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index a7901ed358..e215413c79 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -26,6 +26,7 @@ #include <linux/poison.h> #include <linux/module.h> #include <linux/cpumask.h> +#include <linux/bpf_mem_alloc.h> #include <net/xdp.h> #include "disasm.h" @@ -41,6 +42,9 @@ static const struct bpf_verifier_ops * const bpf_verifier_ops[] = { #undef BPF_LINK_TYPE }; +struct bpf_mem_alloc bpf_global_percpu_ma; +static bool bpf_global_percpu_ma_set; + /* bpf_check() is a static code analyzer that walks eBPF program * instruction by instruction and updates register/stack state. * All paths of conditional branches are analyzed until 'bpf_exit' insn. @@ -304,7 +308,7 @@ struct bpf_kfunc_call_arg_meta { /* arg_{btf,btf_id,owning_ref} are used by kfunc-specific handling, * generally to pass info about user-defined local kptr types to later * verification logic - * bpf_obj_drop + * bpf_obj_drop/bpf_percpu_obj_drop * Record the local kptr type to be drop'd * bpf_refcount_acquire (via KF_ARG_PTR_TO_REFCOUNTED_KPTR arg type) * Record the local kptr type to be refcount_incr'd and use @@ -336,6 +340,7 @@ struct bpf_kfunc_call_arg_meta { struct btf *btf_vmlinux; static DEFINE_MUTEX(bpf_verifier_lock); +static DEFINE_MUTEX(bpf_percpu_ma_lock); static const struct bpf_line_info * find_linfo(const struct bpf_verifier_env *env, u32 insn_off) @@ -543,6 +548,7 @@ static bool is_dynptr_ref_function(enum bpf_func_id func_id) } static bool is_sync_callback_calling_kfunc(u32 btf_id); +static bool is_bpf_throw_kfunc(struct bpf_insn *insn); static bool is_sync_callback_calling_function(enum bpf_func_id func_id) { @@ -1183,7 +1189,12 @@ static bool is_dynptr_type_expected(struct bpf_verifier_env *env, struct bpf_reg static void __mark_reg_known_zero(struct bpf_reg_state *reg); +static bool in_rcu_cs(struct bpf_verifier_env *env); + +static bool is_kfunc_rcu_protected(struct bpf_kfunc_call_arg_meta *meta); + static int mark_stack_slots_iter(struct bpf_verifier_env *env, + struct bpf_kfunc_call_arg_meta *meta, struct bpf_reg_state *reg, int insn_idx, struct btf *btf, u32 btf_id, int nr_slots) { @@ -1204,6 +1215,12 @@ static int mark_stack_slots_iter(struct bpf_verifier_env *env, __mark_reg_known_zero(st); st->type = PTR_TO_STACK; /* we don't have dedicated reg type */ + if (is_kfunc_rcu_protected(meta)) { + if (in_rcu_cs(env)) + st->type |= MEM_RCU; + else + st->type |= PTR_UNTRUSTED; + } st->live |= REG_LIVE_WRITTEN; st->ref_obj_id = i == 0 ? id : 0; st->iter.btf = btf; @@ -1278,7 +1295,7 @@ static bool is_iter_reg_valid_uninit(struct bpf_verifier_env *env, return true; } -static bool is_iter_reg_valid_init(struct bpf_verifier_env *env, struct bpf_reg_state *reg, +static int is_iter_reg_valid_init(struct bpf_verifier_env *env, struct bpf_reg_state *reg, struct btf *btf, u32 btf_id, int nr_slots) { struct bpf_func_state *state = func(env, reg); @@ -1286,26 +1303,28 @@ static bool is_iter_reg_valid_init(struct bpf_verifier_env *env, struct bpf_reg_ spi = iter_get_spi(env, reg, nr_slots); if (spi < 0) - return false; + return -EINVAL; for (i = 0; i < nr_slots; i++) { struct bpf_stack_state *slot = &state->stack[spi - i]; struct bpf_reg_state *st = &slot->spilled_ptr; + if (st->type & PTR_UNTRUSTED) + return -EPROTO; /* only main (first) slot has ref_obj_id set */ if (i == 0 && !st->ref_obj_id) - return false; + return -EINVAL; if (i != 0 && st->ref_obj_id) - return false; + return -EINVAL; if (st->iter.btf != btf || st->iter.btf_id != btf_id) - return false; + return -EINVAL; for (j = 0; j < BPF_REG_SIZE; j++) if (slot->slot_type[j] != STACK_ITER) - return false; + return -EINVAL; } - return true; + return 0; } /* Check if given stack slot is "special": @@ -1352,6 +1371,50 @@ static void scrub_spilled_slot(u8 *stype) *stype = STACK_MISC; } +static void print_scalar_ranges(struct bpf_verifier_env *env, + const struct bpf_reg_state *reg, + const char **sep) +{ + struct { + const char *name; + u64 val; + bool omit; + } minmaxs[] = { + {"smin", reg->smin_value, reg->smin_value == S64_MIN}, + {"smax", reg->smax_value, reg->smax_value == S64_MAX}, + {"umin", reg->umin_value, reg->umin_value == 0}, + {"umax", reg->umax_value, reg->umax_value == U64_MAX}, + {"smin32", (s64)reg->s32_min_value, reg->s32_min_value == S32_MIN}, + {"smax32", (s64)reg->s32_max_value, reg->s32_max_value == S32_MAX}, + {"umin32", reg->u32_min_value, reg->u32_min_value == 0}, + {"umax32", reg->u32_max_value, reg->u32_max_value == U32_MAX}, + }, *m1, *m2, *mend = &minmaxs[ARRAY_SIZE(minmaxs)]; + bool neg1, neg2; + + for (m1 = &minmaxs[0]; m1 < mend; m1++) { + if (m1->omit) + continue; + + neg1 = m1->name[0] == 's' && (s64)m1->val < 0; + + verbose(env, "%s%s=", *sep, m1->name); + *sep = ","; + + for (m2 = m1 + 2; m2 < mend; m2 += 2) { + if (m2->omit || m2->val != m1->val) + continue; + /* don't mix negatives with positives */ + neg2 = m2->name[0] == 's' && (s64)m2->val < 0; + if (neg2 != neg1) + continue; + m2->omit = true; + verbose(env, "%s=", m2->name); + } + + verbose(env, m1->name[0] == 's' ? "%lld" : "%llu", m1->val); + } +} + static void print_verifier_state(struct bpf_verifier_env *env, const struct bpf_func_state *state, bool print_all) @@ -1415,34 +1478,13 @@ static void print_verifier_state(struct bpf_verifier_env *env, */ verbose_a("imm=%llx", reg->var_off.value); } else { - if (reg->smin_value != reg->umin_value && - reg->smin_value != S64_MIN) - verbose_a("smin=%lld", (long long)reg->smin_value); - if (reg->smax_value != reg->umax_value && - reg->smax_value != S64_MAX) - verbose_a("smax=%lld", (long long)reg->smax_value); - if (reg->umin_value != 0) - verbose_a("umin=%llu", (unsigned long long)reg->umin_value); - if (reg->umax_value != U64_MAX) - verbose_a("umax=%llu", (unsigned long long)reg->umax_value); + print_scalar_ranges(env, reg, &sep); if (!tnum_is_unknown(reg->var_off)) { char tn_buf[48]; tnum_strn(tn_buf, sizeof(tn_buf), reg->var_off); verbose_a("var_off=%s", tn_buf); } - if (reg->s32_min_value != reg->smin_value && - reg->s32_min_value != S32_MIN) - verbose_a("s32_min=%d", (int)(reg->s32_min_value)); - if (reg->s32_max_value != reg->smax_value && - reg->s32_max_value != S32_MAX) - verbose_a("s32_max=%d", (int)(reg->s32_max_value)); - if (reg->u32_min_value != reg->umin_value && - reg->u32_min_value != U32_MIN) - verbose_a("u32_min=%d", (int)(reg->u32_min_value)); - if (reg->u32_max_value != reg->umax_value && - reg->u32_max_value != U32_MAX) - verbose_a("u32_max=%d", (int)(reg->u32_max_value)); } #undef verbose_a @@ -1768,7 +1810,9 @@ static int copy_verifier_state(struct bpf_verifier_state *dst_state, return -ENOMEM; dst_state->jmp_history_cnt = src->jmp_history_cnt; - /* if dst has more stack frames then src frame, free them */ + /* if dst has more stack frames then src frame, free them, this is also + * necessary in case of exceptional exits using bpf_throw. + */ for (i = src->curframe + 1; i <= dst_state->curframe; i++) { free_func_state(dst_state->frame[i]); dst_state->frame[i] = NULL; @@ -2669,6 +2713,68 @@ static int add_subprog(struct bpf_verifier_env *env, int off) return env->subprog_cnt - 1; } +static int bpf_find_exception_callback_insn_off(struct bpf_verifier_env *env) +{ + struct bpf_prog_aux *aux = env->prog->aux; + struct btf *btf = aux->btf; + const struct btf_type *t; + u32 main_btf_id, id; + const char *name; + int ret, i; + + /* Non-zero func_info_cnt implies valid btf */ + if (!aux->func_info_cnt) + return 0; + main_btf_id = aux->func_info[0].type_id; + + t = btf_type_by_id(btf, main_btf_id); + if (!t) { + verbose(env, "invalid btf id for main subprog in func_info\n"); + return -EINVAL; + } + + name = btf_find_decl_tag_value(btf, t, -1, "exception_callback:"); + if (IS_ERR(name)) { + ret = PTR_ERR(name); + /* If there is no tag present, there is no exception callback */ + if (ret == -ENOENT) + ret = 0; + else if (ret == -EEXIST) + verbose(env, "multiple exception callback tags for main subprog\n"); + return ret; + } + + ret = btf_find_by_name_kind(btf, name, BTF_KIND_FUNC); + if (ret < 0) { + verbose(env, "exception callback '%s' could not be found in BTF\n", name); + return ret; + } + id = ret; + t = btf_type_by_id(btf, id); + if (btf_func_linkage(t) != BTF_FUNC_GLOBAL) { + verbose(env, "exception callback '%s' must have global linkage\n", name); + return -EINVAL; + } + ret = 0; + for (i = 0; i < aux->func_info_cnt; i++) { + if (aux->func_info[i].type_id != id) + continue; + ret = aux->func_info[i].insn_off; + /* Further func_info and subprog checks will also happen + * later, so assume this is the right insn_off for now. + */ + if (!ret) { + verbose(env, "invalid exception callback insn_off in func_info: 0\n"); + ret = -EINVAL; + } + } + if (!ret) { + verbose(env, "exception callback type id not found in func_info\n"); + ret = -EINVAL; + } + return ret; +} + #define MAX_KFUNC_DESCS 256 #define MAX_KFUNC_BTFS 256 @@ -3008,8 +3114,8 @@ bpf_jit_find_kfunc_model(const struct bpf_prog *prog, static int add_subprog_and_kfunc(struct bpf_verifier_env *env) { struct bpf_subprog_info *subprog = env->subprog_info; + int i, ret, insn_cnt = env->prog->len, ex_cb_insn; struct bpf_insn *insn = env->prog->insnsi; - int i, ret, insn_cnt = env->prog->len; /* Add entry function. */ ret = add_subprog(env, 0); @@ -3035,6 +3141,26 @@ static int add_subprog_and_kfunc(struct bpf_verifier_env *env) return ret; } + ret = bpf_find_exception_callback_insn_off(env); + if (ret < 0) + return ret; + ex_cb_insn = ret; + + /* If ex_cb_insn > 0, this means that the main program has a subprog + * marked using BTF decl tag to serve as the exception callback. + */ + if (ex_cb_insn) { + ret = add_subprog(env, ex_cb_insn); + if (ret < 0) + return ret; + for (i = 1; i < env->subprog_cnt; i++) { + if (env->subprog_info[i].start != ex_cb_insn) + continue; + env->exception_callback_subprog = i; + break; + } + } + /* Add a fake 'exit' subprog which could simplify subprog iteration * logic. 'subprog_cnt' should not be increased. */ @@ -3083,7 +3209,7 @@ next: if (i == subprog_end - 1) { /* to avoid fall-through from one subprog into another * the last insn of the subprog should be either exit - * or unconditional jump back + * or unconditional jump back or bpf_throw call */ if (code != (BPF_JMP | BPF_EXIT) && code != (BPF_JMP32 | BPF_JA) && @@ -3244,7 +3370,7 @@ static bool is_reg64(struct bpf_verifier_env *env, struct bpf_insn *insn, if (class == BPF_LDX) { if (t != SRC_OP) - return BPF_SIZE(code) == BPF_DW; + return BPF_SIZE(code) == BPF_DW || BPF_MODE(code) == BPF_MEMSX; /* LDX source must be ptr. */ return true; } @@ -5243,6 +5369,8 @@ static int map_kptr_match_type(struct bpf_verifier_env *env, perm_flags |= PTR_UNTRUSTED; } else { perm_flags = PTR_MAYBE_NULL | MEM_ALLOC; + if (kptr_field->type == BPF_KPTR_PERCPU) + perm_flags |= MEM_PERCPU; } if (base_type(reg->type) != PTR_TO_BTF_ID || (type_flag(reg->type) & ~perm_flags)) @@ -5286,7 +5414,7 @@ static int map_kptr_match_type(struct bpf_verifier_env *env, */ if (!btf_struct_ids_match(&env->log, reg->btf, reg->btf_id, reg->off, kptr_field->kptr.btf, kptr_field->kptr.btf_id, - kptr_field->type == BPF_KPTR_REF)) + kptr_field->type != BPF_KPTR_UNREF)) goto bad_type; return 0; bad_type: @@ -5314,7 +5442,9 @@ static bool in_rcu_cs(struct bpf_verifier_env *env) /* Once GCC supports btf_type_tag the following mechanism will be replaced with tag check */ BTF_SET_START(rcu_protected_types) BTF_ID(struct, prog_test_ref_kfunc) +#ifdef CONFIG_CGROUPS BTF_ID(struct, cgroup) +#endif BTF_ID(struct, bpf_cpumask) BTF_ID(struct, task_struct) BTF_SET_END(rcu_protected_types) @@ -5330,7 +5460,18 @@ static bool rcu_safe_kptr(const struct btf_field *field) { const struct btf_field_kptr *kptr = &field->kptr; - return field->type == BPF_KPTR_REF && rcu_protected_object(kptr->btf, kptr->btf_id); + return field->type == BPF_KPTR_PERCPU || + (field->type == BPF_KPTR_REF && rcu_protected_object(kptr->btf, kptr->btf_id)); +} + +static u32 btf_ld_kptr_type(struct bpf_verifier_env *env, struct btf_field *kptr_field) +{ + if (rcu_safe_kptr(kptr_field) && in_rcu_cs(env)) { + if (kptr_field->type != BPF_KPTR_PERCPU) + return PTR_MAYBE_NULL | MEM_RCU; + return PTR_MAYBE_NULL | MEM_RCU | MEM_PERCPU; + } + return PTR_MAYBE_NULL | PTR_UNTRUSTED; } static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, @@ -5356,7 +5497,8 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, /* We only allow loading referenced kptr, since it will be marked as * untrusted, similar to unreferenced kptr. */ - if (class != BPF_LDX && kptr_field->type == BPF_KPTR_REF) { + if (class != BPF_LDX && + (kptr_field->type == BPF_KPTR_REF || kptr_field->type == BPF_KPTR_PERCPU)) { verbose(env, "store to referenced kptr disallowed\n"); return -EACCES; } @@ -5367,10 +5509,7 @@ static int check_map_kptr_access(struct bpf_verifier_env *env, u32 regno, * value from map as PTR_TO_BTF_ID, with the correct type. */ mark_btf_ld_reg(env, cur_regs(env), value_regno, PTR_TO_BTF_ID, kptr_field->kptr.btf, - kptr_field->kptr.btf_id, - rcu_safe_kptr(kptr_field) && in_rcu_cs(env) ? - PTR_MAYBE_NULL | MEM_RCU : - PTR_MAYBE_NULL | PTR_UNTRUSTED); + kptr_field->kptr.btf_id, btf_ld_kptr_type(env, kptr_field)); /* For mark_ptr_or_null_reg */ val_reg->id = ++env->id_gen; } else if (class == BPF_STX) { @@ -5424,6 +5563,7 @@ static int check_map_access(struct bpf_verifier_env *env, u32 regno, switch (field->type) { case BPF_KPTR_UNREF: case BPF_KPTR_REF: + case BPF_KPTR_PERCPU: if (src != ACCESS_DIRECT) { verbose(env, "kptr cannot be accessed indirectly by helper\n"); return -EACCES; @@ -5877,6 +6017,27 @@ continue_func: for (; i < subprog_end; i++) { int next_insn, sidx; + if (bpf_pseudo_kfunc_call(insn + i) && !insn[i].off) { + bool err = false; + + if (!is_bpf_throw_kfunc(insn + i)) + continue; + if (subprog[idx].is_cb) + err = true; + for (int c = 0; c < frame && !err; c++) { + if (subprog[ret_prog[c]].is_cb) { + err = true; + break; + } + } + if (!err) + continue; + verbose(env, + "bpf_throw kfunc (insn %d) cannot be called from callback subprog %d\n", + i, idx); + return -EINVAL; + } + if (!bpf_pseudo_call(insn + i) && !bpf_pseudo_func(insn + i)) continue; /* remember insn and function to return to */ @@ -5899,6 +6060,10 @@ continue_func: /* async callbacks don't increase bpf prog stack size unless called directly */ if (!bpf_pseudo_call(insn + i)) continue; + if (subprog[sidx].is_exception_cb) { + verbose(env, "insn %d cannot call exception cb directly\n", i); + return -EINVAL; + } } i = next_insn; idx = sidx; @@ -5920,8 +6085,13 @@ continue_func: * tail call counter throughout bpf2bpf calls combined with tailcalls */ if (tail_call_reachable) - for (j = 0; j < frame; j++) + for (j = 0; j < frame; j++) { + if (subprog[ret_prog[j]].is_exception_cb) { + verbose(env, "cannot tail call within exception cb\n"); + return -EINVAL; + } subprog[ret_prog[j]].tail_call_reachable = true; + } if (subprog[0].tail_call_reachable) env->prog->aux->tail_call_reachable = true; @@ -6437,7 +6607,7 @@ static int check_ptr_to_btf_access(struct bpf_verifier_env *env, } if (type_is_alloc(reg->type) && !type_is_non_owning_ref(reg->type) && - !reg->ref_obj_id) { + !(reg->type & MEM_RCU) && !reg->ref_obj_id) { verbose(env, "verifier internal error: ref_obj_id for allocated object must be non-zero\n"); return -EFAULT; } @@ -7542,7 +7712,7 @@ static int process_kptr_func(struct bpf_verifier_env *env, int regno, verbose(env, "off=%d doesn't point to kptr\n", kptr_off); return -EACCES; } - if (kptr_field->type != BPF_KPTR_REF) { + if (kptr_field->type != BPF_KPTR_REF && kptr_field->type != BPF_KPTR_PERCPU) { verbose(env, "off=%d kptr isn't referenced kptr\n", kptr_off); return -EACCES; } @@ -7713,15 +7883,24 @@ static int process_iter_arg(struct bpf_verifier_env *env, int regno, int insn_id return err; } - err = mark_stack_slots_iter(env, reg, insn_idx, meta->btf, btf_id, nr_slots); + err = mark_stack_slots_iter(env, meta, reg, insn_idx, meta->btf, btf_id, nr_slots); if (err) return err; } else { /* iter_next() or iter_destroy() expect initialized iter state*/ - if (!is_iter_reg_valid_init(env, reg, meta->btf, btf_id, nr_slots)) { + err = is_iter_reg_valid_init(env, reg, meta->btf, btf_id, nr_slots); + switch (err) { + case 0: + break; + case -EINVAL: verbose(env, "expected an initialized iter_%s as arg #%d\n", iter_type_str(meta->btf, btf_id), regno); - return -EINVAL; + return err; + case -EPROTO: + verbose(env, "expected an RCU CS when using %s\n", meta->func_name); + return err; + default: + return err; } spi = iter_get_spi(env, reg, nr_slots); @@ -8087,6 +8266,7 @@ static const struct bpf_reg_types btf_ptr_types = { static const struct bpf_reg_types percpu_btf_ptr_types = { .types = { PTR_TO_BTF_ID | MEM_PERCPU, + PTR_TO_BTF_ID | MEM_PERCPU | MEM_RCU, PTR_TO_BTF_ID | MEM_PERCPU | PTR_TRUSTED, } }; @@ -8165,8 +8345,10 @@ static int check_reg_type(struct bpf_verifier_env *env, u32 regno, if (base_type(arg_type) == ARG_PTR_TO_MEM) type &= ~DYNPTR_TYPE_FLAG_MASK; - if (meta->func_id == BPF_FUNC_kptr_xchg && type_is_alloc(type)) + if (meta->func_id == BPF_FUNC_kptr_xchg && type_is_alloc(type)) { type &= ~MEM_ALLOC; + type &= ~MEM_PERCPU; + } for (i = 0; i < ARRAY_SIZE(compatible->types); i++) { expected = compatible->types[i]; @@ -8249,6 +8431,7 @@ found: break; } case PTR_TO_BTF_ID | MEM_ALLOC: + case PTR_TO_BTF_ID | MEM_PERCPU | MEM_ALLOC: if (meta->func_id != BPF_FUNC_spin_lock && meta->func_id != BPF_FUNC_spin_unlock && meta->func_id != BPF_FUNC_kptr_xchg) { verbose(env, "verifier internal error: unimplemented handling of MEM_ALLOC\n"); @@ -8260,6 +8443,7 @@ found: } break; case PTR_TO_BTF_ID | MEM_PERCPU: + case PTR_TO_BTF_ID | MEM_PERCPU | MEM_RCU: case PTR_TO_BTF_ID | MEM_PERCPU | PTR_TRUSTED: /* Handled by helper specific checks */ break; @@ -9254,6 +9438,7 @@ static int push_callback_call(struct bpf_verifier_env *env, struct bpf_insn *ins * interested in validating only BPF helpers that can call subprogs as * callbacks */ + env->subprog_info[subprog].is_cb = true; if (bpf_pseudo_kfunc_call(insn) && !is_sync_callback_calling_kfunc(insn->imm)) { verbose(env, "verifier bug: kfunc %s#%d not marked as callback-calling\n", @@ -9674,7 +9859,8 @@ static int prepare_func_exit(struct bpf_verifier_env *env, int *insn_idx) verbose(env, "to caller at %d:\n", *insn_idx); print_verifier_state(env, caller, true); } - /* clear everything in the callee */ + /* clear everything in the callee. In case of exceptional exits using + * bpf_throw, this will be done by copy_verifier_state for extra frames. */ free_func_state(callee); state->frame[state->curframe--] = NULL; @@ -9816,17 +10002,17 @@ record_func_key(struct bpf_verifier_env *env, struct bpf_call_arg_meta *meta, return 0; } -static int check_reference_leak(struct bpf_verifier_env *env) +static int check_reference_leak(struct bpf_verifier_env *env, bool exception_exit) { struct bpf_func_state *state = cur_func(env); bool refs_lingering = false; int i; - if (state->frameno && !state->in_callback_fn) + if (!exception_exit && state->frameno && !state->in_callback_fn) return 0; for (i = 0; i < state->acquired_refs; i++) { - if (state->in_callback_fn && state->refs[i].callback_ref != state->frameno) + if (!exception_exit && state->in_callback_fn && state->refs[i].callback_ref != state->frameno) continue; verbose(env, "Unreleased reference id=%d alloc_insn=%d\n", state->refs[i].id, state->refs[i].insn_idx); @@ -9933,6 +10119,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn int *insn_idx_p) { enum bpf_prog_type prog_type = resolve_prog_type(env->prog); + bool returns_cpu_specific_alloc_ptr = false; const struct bpf_func_proto *fn = NULL; enum bpf_return_type ret_type; enum bpf_type_flag ret_flag; @@ -10043,6 +10230,26 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn return -EFAULT; } err = unmark_stack_slots_dynptr(env, ®s[meta.release_regno]); + } else if (func_id == BPF_FUNC_kptr_xchg && meta.ref_obj_id) { + u32 ref_obj_id = meta.ref_obj_id; + bool in_rcu = in_rcu_cs(env); + struct bpf_func_state *state; + struct bpf_reg_state *reg; + + err = release_reference_state(cur_func(env), ref_obj_id); + if (!err) { + bpf_for_each_reg_in_vstate(env->cur_state, state, reg, ({ + if (reg->ref_obj_id == ref_obj_id) { + if (in_rcu && (reg->type & MEM_ALLOC) && (reg->type & MEM_PERCPU)) { + reg->ref_obj_id = 0; + reg->type &= ~MEM_ALLOC; + reg->type |= MEM_RCU; + } else { + mark_reg_invalid(env, reg); + } + } + })); + } } else if (meta.ref_obj_id) { err = release_reference(env, meta.ref_obj_id); } else if (register_is_null(®s[meta.release_regno])) { @@ -10060,7 +10267,7 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn switch (func_id) { case BPF_FUNC_tail_call: - err = check_reference_leak(env); + err = check_reference_leak(env, false); if (err) { verbose(env, "tail_call would lead to reference leak\n"); return err; @@ -10184,6 +10391,23 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn break; } + case BPF_FUNC_per_cpu_ptr: + case BPF_FUNC_this_cpu_ptr: + { + struct bpf_reg_state *reg = ®s[BPF_REG_1]; + const struct btf_type *type; + + if (reg->type & MEM_RCU) { + type = btf_type_by_id(reg->btf, reg->btf_id); + if (!type || !btf_type_is_struct(type)) { + verbose(env, "Helper has invalid btf/btf_id in R1\n"); + return -EFAULT; + } + returns_cpu_specific_alloc_ptr = true; + env->insn_aux_data[insn_idx].call_with_percpu_alloc_ptr = true; + } + break; + } case BPF_FUNC_user_ringbuf_drain: err = push_callback_call(env, insn, insn_idx, meta.subprogno, set_user_ringbuf_callback_state); @@ -10273,14 +10497,18 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn regs[BPF_REG_0].type = PTR_TO_MEM | ret_flag; regs[BPF_REG_0].mem_size = tsize; } else { - /* MEM_RDONLY may be carried from ret_flag, but it - * doesn't apply on PTR_TO_BTF_ID. Fold it, otherwise - * it will confuse the check of PTR_TO_BTF_ID in - * check_mem_access(). - */ - ret_flag &= ~MEM_RDONLY; + if (returns_cpu_specific_alloc_ptr) { + regs[BPF_REG_0].type = PTR_TO_BTF_ID | MEM_ALLOC | MEM_RCU; + } else { + /* MEM_RDONLY may be carried from ret_flag, but it + * doesn't apply on PTR_TO_BTF_ID. Fold it, otherwise + * it will confuse the check of PTR_TO_BTF_ID in + * check_mem_access(). + */ + ret_flag &= ~MEM_RDONLY; + regs[BPF_REG_0].type = PTR_TO_BTF_ID | ret_flag; + } - regs[BPF_REG_0].type = PTR_TO_BTF_ID | ret_flag; regs[BPF_REG_0].btf = meta.ret_btf; regs[BPF_REG_0].btf_id = meta.ret_btf_id; } @@ -10296,8 +10524,11 @@ static int check_helper_call(struct bpf_verifier_env *env, struct bpf_insn *insn if (func_id == BPF_FUNC_kptr_xchg) { ret_btf = meta.kptr_field->kptr.btf; ret_btf_id = meta.kptr_field->kptr.btf_id; - if (!btf_is_kernel(ret_btf)) + if (!btf_is_kernel(ret_btf)) { regs[BPF_REG_0].type |= MEM_ALLOC; + if (meta.kptr_field->type == BPF_KPTR_PERCPU) + regs[BPF_REG_0].type |= MEM_PERCPU; + } } else { if (fn->ret_btf_id == BPF_PTR_POISON) { verbose(env, "verifier internal error:"); @@ -10444,6 +10675,11 @@ static bool is_kfunc_rcu(struct bpf_kfunc_call_arg_meta *meta) return meta->kfunc_flags & KF_RCU; } +static bool is_kfunc_rcu_protected(struct bpf_kfunc_call_arg_meta *meta) +{ + return meta->kfunc_flags & KF_RCU_PROTECTED; +} + static bool __kfunc_param_match_suffix(const struct btf *btf, const struct btf_param *arg, const char *suffix) @@ -10518,6 +10754,11 @@ static bool is_kfunc_arg_refcounted_kptr(const struct btf *btf, const struct btf return __kfunc_param_match_suffix(btf, arg, "__refcounted_kptr"); } +static bool is_kfunc_arg_nullable(const struct btf *btf, const struct btf_param *arg) +{ + return __kfunc_param_match_suffix(btf, arg, "__nullable"); +} + static bool is_kfunc_arg_scalar_with_name(const struct btf *btf, const struct btf_param *arg, const char *name) @@ -10660,6 +10901,7 @@ enum kfunc_ptr_arg_type { KF_ARG_PTR_TO_CALLBACK, KF_ARG_PTR_TO_RB_ROOT, KF_ARG_PTR_TO_RB_NODE, + KF_ARG_PTR_TO_NULL, }; enum special_kfunc_type { @@ -10682,6 +10924,10 @@ enum special_kfunc_type { KF_bpf_dynptr_slice, KF_bpf_dynptr_slice_rdwr, KF_bpf_dynptr_clone, + KF_bpf_percpu_obj_new_impl, + KF_bpf_percpu_obj_drop_impl, + KF_bpf_throw, + KF_bpf_iter_css_task_new, }; BTF_SET_START(special_kfunc_set) @@ -10702,6 +10948,12 @@ BTF_ID(func, bpf_dynptr_from_xdp) BTF_ID(func, bpf_dynptr_slice) BTF_ID(func, bpf_dynptr_slice_rdwr) BTF_ID(func, bpf_dynptr_clone) +BTF_ID(func, bpf_percpu_obj_new_impl) +BTF_ID(func, bpf_percpu_obj_drop_impl) +BTF_ID(func, bpf_throw) +#ifdef CONFIG_CGROUPS +BTF_ID(func, bpf_iter_css_task_new) +#endif BTF_SET_END(special_kfunc_set) BTF_ID_LIST(special_kfunc_list) @@ -10724,6 +10976,14 @@ BTF_ID(func, bpf_dynptr_from_xdp) BTF_ID(func, bpf_dynptr_slice) BTF_ID(func, bpf_dynptr_slice_rdwr) BTF_ID(func, bpf_dynptr_clone) +BTF_ID(func, bpf_percpu_obj_new_impl) +BTF_ID(func, bpf_percpu_obj_drop_impl) +BTF_ID(func, bpf_throw) +#ifdef CONFIG_CGROUPS +BTF_ID(func, bpf_iter_css_task_new) +#else +BTF_ID_UNUSED +#endif static bool is_kfunc_ret_null(struct bpf_kfunc_call_arg_meta *meta) { @@ -10804,6 +11064,8 @@ get_kfunc_ptr_arg_type(struct bpf_verifier_env *env, if (is_kfunc_arg_callback(env, meta->btf, &args[argno])) return KF_ARG_PTR_TO_CALLBACK; + if (is_kfunc_arg_nullable(meta->btf, &args[argno]) && register_is_null(reg)) + return KF_ARG_PTR_TO_NULL; if (argno + 1 < nargs && (is_kfunc_arg_mem_size(meta->btf, &args[argno + 1], ®s[regno + 1]) || @@ -11041,6 +11303,12 @@ static bool is_sync_callback_calling_kfunc(u32 btf_id) return btf_id == special_kfunc_list[KF_bpf_rbtree_add_impl]; } +static bool is_bpf_throw_kfunc(struct bpf_insn *insn) +{ + return bpf_pseudo_kfunc_call(insn) && insn->off == 0 && + insn->imm == special_kfunc_list[KF_bpf_throw]; +} + static bool is_rbtree_lock_required_kfunc(u32 btf_id) { return is_bpf_rbtree_api_kfunc(btf_id); @@ -11248,6 +11516,28 @@ static int process_kf_arg_ptr_to_rbtree_node(struct bpf_verifier_env *env, &meta->arg_rbtree_root.field); } +/* + * css_task iter allowlist is needed to avoid dead locking on css_set_lock. + * LSM hooks and iters (both sleepable and non-sleepable) are safe. + * Any sleepable progs are also safe since bpf_check_attach_target() enforce + * them can only be attached to some specific hook points. + */ +static bool check_css_task_iter_allowlist(struct bpf_verifier_env *env) +{ + enum bpf_prog_type prog_type = resolve_prog_type(env->prog); + + switch (prog_type) { + case BPF_PROG_TYPE_LSM: + return true; + case BPF_PROG_TYPE_TRACING: + if (env->prog->expected_attach_type == BPF_TRACE_ITER) + return true; + fallthrough; + default: + return env->prog->aux->sleepable; + } +} + static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_arg_meta *meta, int insn_idx) { @@ -11334,7 +11624,8 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ } if ((is_kfunc_trusted_args(meta) || is_kfunc_rcu(meta)) && - (register_is_null(reg) || type_may_be_null(reg->type))) { + (register_is_null(reg) || type_may_be_null(reg->type)) && + !is_kfunc_arg_nullable(meta->btf, &args[i])) { verbose(env, "Possibly NULL pointer passed to trusted arg%d\n", i); return -EACCES; } @@ -11359,6 +11650,8 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ return kf_arg_type; switch (kf_arg_type) { + case KF_ARG_PTR_TO_NULL: + continue; case KF_ARG_PTR_TO_ALLOC_BTF_ID: case KF_ARG_PTR_TO_BTF_ID: if (!is_kfunc_trusted_args(meta) && !is_kfunc_rcu(meta)) @@ -11418,7 +11711,17 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ } break; case KF_ARG_PTR_TO_ALLOC_BTF_ID: - if (reg->type != (PTR_TO_BTF_ID | MEM_ALLOC)) { + if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC)) { + if (meta->func_id != special_kfunc_list[KF_bpf_obj_drop_impl]) { + verbose(env, "arg#%d expected for bpf_obj_drop_impl()\n", i); + return -EINVAL; + } + } else if (reg->type == (PTR_TO_BTF_ID | MEM_ALLOC | MEM_PERCPU)) { + if (meta->func_id != special_kfunc_list[KF_bpf_percpu_obj_drop_impl]) { + verbose(env, "arg#%d expected for bpf_percpu_obj_drop_impl()\n", i); + return -EINVAL; + } + } else { verbose(env, "arg#%d expected pointer to allocated object\n", i); return -EINVAL; } @@ -11426,8 +11729,7 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ verbose(env, "allocated object must be referenced\n"); return -EINVAL; } - if (meta->btf == btf_vmlinux && - meta->func_id == special_kfunc_list[KF_bpf_obj_drop_impl]) { + if (meta->btf == btf_vmlinux) { meta->arg_btf = reg->btf; meta->arg_btf_id = reg->btf_id; } @@ -11489,6 +11791,12 @@ static int check_kfunc_args(struct bpf_verifier_env *env, struct bpf_kfunc_call_ break; } case KF_ARG_PTR_TO_ITER: + if (meta->func_id == special_kfunc_list[KF_bpf_iter_css_task_new]) { + if (!check_css_task_iter_allowlist(env)) { + verbose(env, "css_task_iter is only allowed in bpf_lsm, bpf_iter and sleepable progs\n"); + return -EINVAL; + } + } ret = process_iter_arg(env, regno, insn_idx, meta); if (ret < 0) return ret; @@ -11700,6 +12008,8 @@ static int fetch_kfunc_meta(struct bpf_verifier_env *env, return 0; } +static int check_return_code(struct bpf_verifier_env *env, int regno); + static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, int *insn_idx_p) { @@ -11761,6 +12071,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, if (env->cur_state->active_rcu_lock) { struct bpf_func_state *state; struct bpf_reg_state *reg; + u32 clear_mask = (1 << STACK_SPILL) | (1 << STACK_ITER); if (in_rbtree_lock_required_cb(env) && (rcu_lock || rcu_unlock)) { verbose(env, "Calling bpf_rcu_read_{lock,unlock} in unnecessary rbtree callback\n"); @@ -11771,7 +12082,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, verbose(env, "nested rcu read lock (kernel function %s)\n", func_name); return -EINVAL; } else if (rcu_unlock) { - bpf_for_each_reg_in_vstate(env->cur_state, state, reg, ({ + bpf_for_each_reg_in_vstate_mask(env->cur_state, state, reg, clear_mask, ({ if (reg->type & MEM_RCU) { reg->type &= ~(MEM_RCU | PTR_MAYBE_NULL); reg->type |= PTR_UNTRUSTED; @@ -11822,6 +12133,24 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, } } + if (meta.func_id == special_kfunc_list[KF_bpf_throw]) { + if (!bpf_jit_supports_exceptions()) { + verbose(env, "JIT does not support calling kfunc %s#%d\n", + func_name, meta.func_id); + return -ENOTSUPP; + } + env->seen_exception = true; + + /* In the case of the default callback, the cookie value passed + * to bpf_throw becomes the return value of the program. + */ + if (!env->exception_callback_subprog) { + err = check_return_code(env, BPF_REG_1); + if (err < 0) + return err; + } + } + for (i = 0; i < CALLER_SAVED_REGS; i++) mark_reg_not_init(env, regs, caller_saved[i]); @@ -11832,6 +12161,7 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, /* Only exception is bpf_obj_new_impl */ if (meta.btf != btf_vmlinux || (meta.func_id != special_kfunc_list[KF_bpf_obj_new_impl] && + meta.func_id != special_kfunc_list[KF_bpf_percpu_obj_new_impl] && meta.func_id != special_kfunc_list[KF_bpf_refcount_acquire_impl])) { verbose(env, "acquire kernel function does not return PTR_TO_BTF_ID\n"); return -EINVAL; @@ -11845,13 +12175,29 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, ptr_type = btf_type_skip_modifiers(desc_btf, t->type, &ptr_type_id); if (meta.btf == btf_vmlinux && btf_id_set_contains(&special_kfunc_set, meta.func_id)) { - if (meta.func_id == special_kfunc_list[KF_bpf_obj_new_impl]) { + if (meta.func_id == special_kfunc_list[KF_bpf_obj_new_impl] || + meta.func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl]) { + struct btf_struct_meta *struct_meta; struct btf *ret_btf; u32 ret_btf_id; - if (unlikely(!bpf_global_ma_set)) + if (meta.func_id == special_kfunc_list[KF_bpf_obj_new_impl] && !bpf_global_ma_set) return -ENOMEM; + if (meta.func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl]) { + if (!bpf_global_percpu_ma_set) { + mutex_lock(&bpf_percpu_ma_lock); + if (!bpf_global_percpu_ma_set) { + err = bpf_mem_alloc_init(&bpf_global_percpu_ma, 0, true); + if (!err) + bpf_global_percpu_ma_set = true; + } + mutex_unlock(&bpf_percpu_ma_lock); + if (err) + return err; + } + } + if (((u64)(u32)meta.arg_constant.value) != meta.arg_constant.value) { verbose(env, "local type ID argument must be in range [0, U32_MAX]\n"); return -EINVAL; @@ -11862,24 +12208,38 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, /* This may be NULL due to user not supplying a BTF */ if (!ret_btf) { - verbose(env, "bpf_obj_new requires prog BTF\n"); + verbose(env, "bpf_obj_new/bpf_percpu_obj_new requires prog BTF\n"); return -EINVAL; } ret_t = btf_type_by_id(ret_btf, ret_btf_id); if (!ret_t || !__btf_type_is_struct(ret_t)) { - verbose(env, "bpf_obj_new type ID argument must be of a struct\n"); + verbose(env, "bpf_obj_new/bpf_percpu_obj_new type ID argument must be of a struct\n"); return -EINVAL; } + struct_meta = btf_find_struct_meta(ret_btf, ret_btf_id); + if (meta.func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl]) { + if (!__btf_type_is_scalar_struct(env, ret_btf, ret_t, 0)) { + verbose(env, "bpf_percpu_obj_new type ID argument must be of a struct of scalars\n"); + return -EINVAL; + } + + if (struct_meta) { + verbose(env, "bpf_percpu_obj_new type ID argument must not contain special fields\n"); + return -EINVAL; + } + } + mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_BTF_ID | MEM_ALLOC; regs[BPF_REG_0].btf = ret_btf; regs[BPF_REG_0].btf_id = ret_btf_id; + if (meta.func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl]) + regs[BPF_REG_0].type |= MEM_PERCPU; insn_aux->obj_new_size = ret_t->size; - insn_aux->kptr_struct_meta = - btf_find_struct_meta(ret_btf, ret_btf_id); + insn_aux->kptr_struct_meta = struct_meta; } else if (meta.func_id == special_kfunc_list[KF_bpf_refcount_acquire_impl]) { mark_reg_known_zero(env, regs, BPF_REG_0); regs[BPF_REG_0].type = PTR_TO_BTF_ID | MEM_ALLOC; @@ -12016,7 +12376,8 @@ static int check_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, regs[BPF_REG_0].id = ++env->id_gen; } else if (btf_type_is_void(t)) { if (meta.btf == btf_vmlinux && btf_id_set_contains(&special_kfunc_set, meta.func_id)) { - if (meta.func_id == special_kfunc_list[KF_bpf_obj_drop_impl]) { + if (meta.func_id == special_kfunc_list[KF_bpf_obj_drop_impl] || + meta.func_id == special_kfunc_list[KF_bpf_percpu_obj_drop_impl]) { insn_aux->kptr_struct_meta = btf_find_struct_meta(meta.arg_btf, meta.arg_btf_id); @@ -13816,12 +14177,16 @@ static int is_branch32_taken(struct bpf_reg_state *reg, u32 val, u8 opcode) return !!tnum_equals_const(subreg, val); else if (val < reg->u32_min_value || val > reg->u32_max_value) return 0; + else if (sval < reg->s32_min_value || sval > reg->s32_max_value) + return 0; break; case BPF_JNE: if (tnum_is_const(subreg)) return !tnum_equals_const(subreg, val); else if (val < reg->u32_min_value || val > reg->u32_max_value) return 1; + else if (sval < reg->s32_min_value || sval > reg->s32_max_value) + return 1; break; case BPF_JSET: if ((~subreg.mask & subreg.value) & val) @@ -13893,12 +14258,16 @@ static int is_branch64_taken(struct bpf_reg_state *reg, u64 val, u8 opcode) return !!tnum_equals_const(reg->var_off, val); else if (val < reg->umin_value || val > reg->umax_value) return 0; + else if (sval < reg->smin_value || sval > reg->smax_value) + return 0; break; case BPF_JNE: if (tnum_is_const(reg->var_off)) return !tnum_equals_const(reg->var_off, val); else if (val < reg->umin_value || val > reg->umax_value) return 1; + else if (sval < reg->smin_value || sval > reg->smax_value) + return 1; break; case BPF_JSET: if ((~reg->var_off.mask & reg->var_off.value) & val) @@ -14854,7 +15223,7 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn) * gen_ld_abs() may terminate the program at runtime, leading to * reference leak. */ - err = check_reference_leak(env); + err = check_reference_leak(env, false); if (err) { verbose(env, "BPF_LD_[ABS|IND] cannot be mixed with socket references\n"); return err; @@ -14903,7 +15272,7 @@ static int check_ld_abs(struct bpf_verifier_env *env, struct bpf_insn *insn) return 0; } -static int check_return_code(struct bpf_verifier_env *env) +static int check_return_code(struct bpf_verifier_env *env, int regno) { struct tnum enforce_attach_type_range = tnum_unknown; const struct bpf_prog *prog = env->prog; @@ -14915,7 +15284,7 @@ static int check_return_code(struct bpf_verifier_env *env) const bool is_subprog = frame->subprogno; /* LSM and struct_ops func-ptr's return type could be "void" */ - if (!is_subprog) { + if (!is_subprog || frame->in_exception_callback_fn) { switch (prog_type) { case BPF_PROG_TYPE_LSM: if (prog->expected_attach_type == BPF_LSM_CGROUP) @@ -14937,22 +15306,22 @@ static int check_return_code(struct bpf_verifier_env *env) * of bpf_exit, which means that program wrote * something into it earlier */ - err = check_reg_arg(env, BPF_REG_0, SRC_OP); + err = check_reg_arg(env, regno, SRC_OP); if (err) return err; - if (is_pointer_value(env, BPF_REG_0)) { - verbose(env, "R0 leaks addr as return value\n"); + if (is_pointer_value(env, regno)) { + verbose(env, "R%d leaks addr as return value\n", regno); return -EACCES; } - reg = cur_regs(env) + BPF_REG_0; + reg = cur_regs(env) + regno; if (frame->in_async_callback_fn) { /* enforce return zero from async callbacks like timer */ if (reg->type != SCALAR_VALUE) { - verbose(env, "In async callback the register R0 is not a known value (%s)\n", - reg_type_str(env, reg->type)); + verbose(env, "In async callback the register R%d is not a known value (%s)\n", + regno, reg_type_str(env, reg->type)); return -EINVAL; } @@ -14963,10 +15332,10 @@ static int check_return_code(struct bpf_verifier_env *env) return 0; } - if (is_subprog) { + if (is_subprog && !frame->in_exception_callback_fn) { if (reg->type != SCALAR_VALUE) { - verbose(env, "At subprogram exit the register R0 is not a scalar value (%s)\n", - reg_type_str(env, reg->type)); + verbose(env, "At subprogram exit the register R%d is not a scalar value (%s)\n", + regno, reg_type_str(env, reg->type)); return -EINVAL; } return 0; @@ -14976,10 +15345,13 @@ static int check_return_code(struct bpf_verifier_env *env) case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: if (env->prog->expected_attach_type == BPF_CGROUP_UDP4_RECVMSG || env->prog->expected_attach_type == BPF_CGROUP_UDP6_RECVMSG || + env->prog->expected_attach_type == BPF_CGROUP_UNIX_RECVMSG || env->prog->expected_attach_type == BPF_CGROUP_INET4_GETPEERNAME || env->prog->expected_attach_type == BPF_CGROUP_INET6_GETPEERNAME || + env->prog->expected_attach_type == BPF_CGROUP_UNIX_GETPEERNAME || env->prog->expected_attach_type == BPF_CGROUP_INET4_GETSOCKNAME || - env->prog->expected_attach_type == BPF_CGROUP_INET6_GETSOCKNAME) + env->prog->expected_attach_type == BPF_CGROUP_INET6_GETSOCKNAME || + env->prog->expected_attach_type == BPF_CGROUP_UNIX_GETSOCKNAME) range = tnum_range(1, 1); if (env->prog->expected_attach_type == BPF_CGROUP_INET4_BIND || env->prog->expected_attach_type == BPF_CGROUP_INET6_BIND) @@ -15048,8 +15420,8 @@ static int check_return_code(struct bpf_verifier_env *env) } if (reg->type != SCALAR_VALUE) { - verbose(env, "At program exit the register R0 is not a known value (%s)\n", - reg_type_str(env, reg->type)); + verbose(env, "At program exit the register R%d is not a known value (%s)\n", + regno, reg_type_str(env, reg->type)); return -EINVAL; } @@ -15325,8 +15697,8 @@ static int check_cfg(struct bpf_verifier_env *env) { int insn_cnt = env->prog->len; int *insn_stack, *insn_state; - int ret = 0; - int i; + int ex_insn_beg, i, ret = 0; + bool ex_done = false; insn_state = env->cfg.insn_state = kvcalloc(insn_cnt, sizeof(int), GFP_KERNEL); if (!insn_state) @@ -15342,6 +15714,7 @@ static int check_cfg(struct bpf_verifier_env *env) insn_stack[0] = 0; /* 0 is the first instruction */ env->cfg.cur_stack = 1; +walk_cfg: while (env->cfg.cur_stack > 0) { int t = insn_stack[env->cfg.cur_stack - 1]; @@ -15368,6 +15741,16 @@ static int check_cfg(struct bpf_verifier_env *env) goto err_free; } + if (env->exception_callback_subprog && !ex_done) { + ex_insn_beg = env->subprog_info[env->exception_callback_subprog].start; + + insn_state[ex_insn_beg] = DISCOVERED; + insn_stack[0] = ex_insn_beg; + env->cfg.cur_stack = 1; + ex_done = true; + goto walk_cfg; + } + for (i = 0; i < insn_cnt; i++) { struct bpf_insn *insn = &env->prog->insnsi[i]; @@ -15415,20 +15798,18 @@ static int check_abnormal_return(struct bpf_verifier_env *env) #define MIN_BPF_FUNCINFO_SIZE 8 #define MAX_FUNCINFO_REC_SIZE 252 -static int check_btf_func(struct bpf_verifier_env *env, - const union bpf_attr *attr, - bpfptr_t uattr) +static int check_btf_func_early(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) { - const struct btf_type *type, *func_proto, *ret_type; - u32 i, nfuncs, urec_size, min_size; u32 krec_size = sizeof(struct bpf_func_info); + const struct btf_type *type, *func_proto; + u32 i, nfuncs, urec_size, min_size; struct bpf_func_info *krecord; - struct bpf_func_info_aux *info_aux = NULL; struct bpf_prog *prog; const struct btf *btf; - bpfptr_t urecord; u32 prev_offset = 0; - bool scalar_return; + bpfptr_t urecord; int ret = -ENOMEM; nfuncs = attr->func_info_cnt; @@ -15438,11 +15819,6 @@ static int check_btf_func(struct bpf_verifier_env *env, return 0; } - if (nfuncs != env->subprog_cnt) { - verbose(env, "number of funcs in func_info doesn't match number of subprogs\n"); - return -EINVAL; - } - urec_size = attr->func_info_rec_size; if (urec_size < MIN_BPF_FUNCINFO_SIZE || urec_size > MAX_FUNCINFO_REC_SIZE || @@ -15460,9 +15836,6 @@ static int check_btf_func(struct bpf_verifier_env *env, krecord = kvcalloc(nfuncs, krec_size, GFP_KERNEL | __GFP_NOWARN); if (!krecord) return -ENOMEM; - info_aux = kcalloc(nfuncs, sizeof(*info_aux), GFP_KERNEL | __GFP_NOWARN); - if (!info_aux) - goto err_free; for (i = 0; i < nfuncs; i++) { ret = bpf_check_uarg_tail_zero(urecord, krec_size, urec_size); @@ -15501,11 +15874,6 @@ static int check_btf_func(struct bpf_verifier_env *env, goto err_free; } - if (env->subprog_info[i].start != krecord[i].insn_off) { - verbose(env, "func_info BTF section doesn't match subprog layout in BPF program\n"); - goto err_free; - } - /* check type_id */ type = btf_type_by_id(btf, krecord[i].type_id); if (!type || !btf_type_is_func(type)) { @@ -15513,12 +15881,77 @@ static int check_btf_func(struct bpf_verifier_env *env, krecord[i].type_id); goto err_free; } - info_aux[i].linkage = BTF_INFO_VLEN(type->info); func_proto = btf_type_by_id(btf, type->type); if (unlikely(!func_proto || !btf_type_is_func_proto(func_proto))) /* btf_func_check() already verified it during BTF load */ goto err_free; + + prev_offset = krecord[i].insn_off; + bpfptr_add(&urecord, urec_size); + } + + prog->aux->func_info = krecord; + prog->aux->func_info_cnt = nfuncs; + return 0; + +err_free: + kvfree(krecord); + return ret; +} + +static int check_btf_func(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) +{ + const struct btf_type *type, *func_proto, *ret_type; + u32 i, nfuncs, urec_size; + struct bpf_func_info *krecord; + struct bpf_func_info_aux *info_aux = NULL; + struct bpf_prog *prog; + const struct btf *btf; + bpfptr_t urecord; + bool scalar_return; + int ret = -ENOMEM; + + nfuncs = attr->func_info_cnt; + if (!nfuncs) { + if (check_abnormal_return(env)) + return -EINVAL; + return 0; + } + if (nfuncs != env->subprog_cnt) { + verbose(env, "number of funcs in func_info doesn't match number of subprogs\n"); + return -EINVAL; + } + + urec_size = attr->func_info_rec_size; + + prog = env->prog; + btf = prog->aux->btf; + + urecord = make_bpfptr(attr->func_info, uattr.is_kernel); + + krecord = prog->aux->func_info; + info_aux = kcalloc(nfuncs, sizeof(*info_aux), GFP_KERNEL | __GFP_NOWARN); + if (!info_aux) + return -ENOMEM; + + for (i = 0; i < nfuncs; i++) { + /* check insn_off */ + ret = -EINVAL; + + if (env->subprog_info[i].start != krecord[i].insn_off) { + verbose(env, "func_info BTF section doesn't match subprog layout in BPF program\n"); + goto err_free; + } + + /* Already checked type_id */ + type = btf_type_by_id(btf, krecord[i].type_id); + info_aux[i].linkage = BTF_INFO_VLEN(type->info); + /* Already checked func_proto */ + func_proto = btf_type_by_id(btf, type->type); + ret_type = btf_type_skip_modifiers(btf, func_proto->type, NULL); scalar_return = btf_type_is_small_int(ret_type) || btf_is_any_enum(ret_type); @@ -15531,17 +15964,13 @@ static int check_btf_func(struct bpf_verifier_env *env, goto err_free; } - prev_offset = krecord[i].insn_off; bpfptr_add(&urecord, urec_size); } - prog->aux->func_info = krecord; - prog->aux->func_info_cnt = nfuncs; prog->aux->func_info_aux = info_aux; return 0; err_free: - kvfree(krecord); kfree(info_aux); return ret; } @@ -15554,7 +15983,8 @@ static void adjust_btf_func(struct bpf_verifier_env *env) if (!aux->func_info) return; - for (i = 0; i < env->subprog_cnt; i++) + /* func_info is not available for hidden subprogs */ + for (i = 0; i < env->subprog_cnt - env->hidden_subprog_cnt; i++) aux->func_info[i].insn_off = env->subprog_info[i].start; } @@ -15758,9 +16188,9 @@ static int check_core_relo(struct bpf_verifier_env *env, return err; } -static int check_btf_info(struct bpf_verifier_env *env, - const union bpf_attr *attr, - bpfptr_t uattr) +static int check_btf_info_early(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) { struct btf *btf; int err; @@ -15780,6 +16210,24 @@ static int check_btf_info(struct bpf_verifier_env *env, } env->prog->aux->btf = btf; + err = check_btf_func_early(env, attr, uattr); + if (err) + return err; + return 0; +} + +static int check_btf_info(struct bpf_verifier_env *env, + const union bpf_attr *attr, + bpfptr_t uattr) +{ + int err; + + if (!attr->func_info_cnt && !attr->line_info_cnt) { + if (check_abnormal_return(env)) + return -EINVAL; + return 0; + } + err = check_btf_func(env, attr, uattr); if (err) return err; @@ -16964,6 +17412,7 @@ static int do_check(struct bpf_verifier_env *env) int prev_insn_idx = -1; for (;;) { + bool exception_exit = false; struct bpf_insn *insn; u8 class; int err; @@ -17178,12 +17627,17 @@ static int do_check(struct bpf_verifier_env *env) return -EINVAL; } } - if (insn->src_reg == BPF_PSEUDO_CALL) + if (insn->src_reg == BPF_PSEUDO_CALL) { err = check_func_call(env, insn, &env->insn_idx); - else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) + } else if (insn->src_reg == BPF_PSEUDO_KFUNC_CALL) { err = check_kfunc_call(env, insn, &env->insn_idx); - else + if (!err && is_bpf_throw_kfunc(insn)) { + exception_exit = true; + goto process_bpf_exit_full; + } + } else { err = check_helper_call(env, insn, &env->insn_idx); + } if (err) return err; @@ -17213,7 +17667,7 @@ static int do_check(struct bpf_verifier_env *env) verbose(env, "BPF_EXIT uses reserved fields\n"); return -EINVAL; } - +process_bpf_exit_full: if (env->cur_state->active_lock.ptr && !in_rbtree_lock_required_cb(env)) { verbose(env, "bpf_spin_unlock is missing\n"); @@ -17232,10 +17686,23 @@ static int do_check(struct bpf_verifier_env *env) * function, for which reference_state must * match caller reference state when it exits. */ - err = check_reference_leak(env); + err = check_reference_leak(env, exception_exit); if (err) return err; + /* The side effect of the prepare_func_exit + * which is being skipped is that it frees + * bpf_func_state. Typically, process_bpf_exit + * will only be hit with outermost exit. + * copy_verifier_state in pop_stack will handle + * freeing of any extra bpf_func_state left over + * from not processing all nested function + * exits. We also skip return code checks as + * they are not needed for exceptional exits. + */ + if (exception_exit) + goto process_bpf_exit; + if (state->curframe) { /* exit from nested function */ err = prepare_func_exit(env, &env->insn_idx); @@ -17245,7 +17712,7 @@ static int do_check(struct bpf_verifier_env *env) continue; } - err = check_return_code(env); + err = check_return_code(env, BPF_REG_0); if (err) return err; process_bpf_exit: @@ -18538,6 +19005,9 @@ static int jit_subprogs(struct bpf_verifier_env *env) } func[i]->aux->num_exentries = num_exentries; func[i]->aux->tail_call_reachable = env->subprog_info[i].tail_call_reachable; + func[i]->aux->exception_cb = env->subprog_info[i].is_exception_cb; + if (!i) + func[i]->aux->exception_boundary = env->seen_exception; func[i] = bpf_int_jit_compile(func[i]); if (!func[i]->jited) { err = -ENOTSUPP; @@ -18577,7 +19047,8 @@ static int jit_subprogs(struct bpf_verifier_env *env) * the call instruction, as an index for this list */ func[i]->aux->func = func; - func[i]->aux->func_cnt = env->subprog_cnt; + func[i]->aux->func_cnt = env->subprog_cnt - env->hidden_subprog_cnt; + func[i]->aux->real_func_cnt = env->subprog_cnt; } for (i = 0; i < env->subprog_cnt; i++) { old_bpf_func = func[i]->bpf_func; @@ -18623,7 +19094,10 @@ static int jit_subprogs(struct bpf_verifier_env *env) prog->aux->extable = func[0]->aux->extable; prog->aux->num_exentries = func[0]->aux->num_exentries; prog->aux->func = func; - prog->aux->func_cnt = env->subprog_cnt; + prog->aux->func_cnt = env->subprog_cnt - env->hidden_subprog_cnt; + prog->aux->real_func_cnt = env->subprog_cnt; + prog->aux->bpf_exception_cb = (void *)func[env->exception_callback_subprog]->bpf_func; + prog->aux->exception_boundary = func[0]->aux->exception_boundary; bpf_prog_jit_attempt_done(prog); return 0; out_free: @@ -18790,21 +19264,35 @@ static int fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, insn->imm = BPF_CALL_IMM(desc->addr); if (insn->off) return 0; - if (desc->func_id == special_kfunc_list[KF_bpf_obj_new_impl]) { + if (desc->func_id == special_kfunc_list[KF_bpf_obj_new_impl] || + desc->func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl]) { struct btf_struct_meta *kptr_struct_meta = env->insn_aux_data[insn_idx].kptr_struct_meta; struct bpf_insn addr[2] = { BPF_LD_IMM64(BPF_REG_2, (long)kptr_struct_meta) }; u64 obj_new_size = env->insn_aux_data[insn_idx].obj_new_size; + if (desc->func_id == special_kfunc_list[KF_bpf_percpu_obj_new_impl] && kptr_struct_meta) { + verbose(env, "verifier internal error: NULL kptr_struct_meta expected at insn_idx %d\n", + insn_idx); + return -EFAULT; + } + insn_buf[0] = BPF_MOV64_IMM(BPF_REG_1, obj_new_size); insn_buf[1] = addr[0]; insn_buf[2] = addr[1]; insn_buf[3] = *insn; *cnt = 4; } else if (desc->func_id == special_kfunc_list[KF_bpf_obj_drop_impl] || + desc->func_id == special_kfunc_list[KF_bpf_percpu_obj_drop_impl] || desc->func_id == special_kfunc_list[KF_bpf_refcount_acquire_impl]) { struct btf_struct_meta *kptr_struct_meta = env->insn_aux_data[insn_idx].kptr_struct_meta; struct bpf_insn addr[2] = { BPF_LD_IMM64(BPF_REG_2, (long)kptr_struct_meta) }; + if (desc->func_id == special_kfunc_list[KF_bpf_percpu_obj_drop_impl] && kptr_struct_meta) { + verbose(env, "verifier internal error: NULL kptr_struct_meta expected at insn_idx %d\n", + insn_idx); + return -EFAULT; + } + if (desc->func_id == special_kfunc_list[KF_bpf_refcount_acquire_impl] && !kptr_struct_meta) { verbose(env, "verifier internal error: kptr_struct_meta expected at insn_idx %d\n", @@ -18845,6 +19333,33 @@ static int fixup_kfunc_call(struct bpf_verifier_env *env, struct bpf_insn *insn, return 0; } +/* The function requires that first instruction in 'patch' is insnsi[prog->len - 1] */ +static int add_hidden_subprog(struct bpf_verifier_env *env, struct bpf_insn *patch, int len) +{ + struct bpf_subprog_info *info = env->subprog_info; + int cnt = env->subprog_cnt; + struct bpf_prog *prog; + + /* We only reserve one slot for hidden subprogs in subprog_info. */ + if (env->hidden_subprog_cnt) { + verbose(env, "verifier internal error: only one hidden subprog supported\n"); + return -EFAULT; + } + /* We're not patching any existing instruction, just appending the new + * ones for the hidden subprog. Hence all of the adjustment operations + * in bpf_patch_insn_data are no-ops. + */ + prog = bpf_patch_insn_data(env, env->prog->len - 1, patch, len); + if (!prog) + return -ENOMEM; + env->prog = prog; + info[cnt + 1].start = info[cnt].start; + info[cnt].start = prog->len - len + 1; + env->subprog_cnt++; + env->hidden_subprog_cnt++; + return 0; +} + /* Do various post-verification rewrites in a single program pass. * These rewrites simplify JIT and interpreter implementations. */ @@ -18863,6 +19378,26 @@ static int do_misc_fixups(struct bpf_verifier_env *env) struct bpf_map *map_ptr; int i, ret, cnt, delta = 0; + if (env->seen_exception && !env->exception_callback_subprog) { + struct bpf_insn patch[] = { + env->prog->insnsi[insn_cnt - 1], + BPF_MOV64_REG(BPF_REG_0, BPF_REG_1), + BPF_EXIT_INSN(), + }; + + ret = add_hidden_subprog(env, patch, ARRAY_SIZE(patch)); + if (ret < 0) + return ret; + prog = env->prog; + insn = prog->insnsi; + + env->exception_callback_subprog = env->subprog_cnt - 1; + /* Don't update insn_cnt, as add_hidden_subprog always appends insns */ + env->subprog_info[env->exception_callback_subprog].is_cb = true; + env->subprog_info[env->exception_callback_subprog].is_async_cb = true; + env->subprog_info[env->exception_callback_subprog].is_exception_cb = true; + } + for (i = 0; i < insn_cnt; i++, insn++) { /* Make divide-by-zero exceptions impossible. */ if (insn->code == (BPF_ALU64 | BPF_MOD | BPF_X) || @@ -19132,6 +19667,25 @@ static int do_misc_fixups(struct bpf_verifier_env *env) goto patch_call_imm; } + /* bpf_per_cpu_ptr() and bpf_this_cpu_ptr() */ + if (env->insn_aux_data[i + delta].call_with_percpu_alloc_ptr) { + /* patch with 'r1 = *(u64 *)(r1 + 0)' since for percpu data, + * bpf_mem_alloc() returns a ptr to the percpu data ptr. + */ + insn_buf[0] = BPF_LDX_MEM(BPF_DW, BPF_REG_1, BPF_REG_1, 0); + insn_buf[1] = *insn; + cnt = 2; + + new_prog = bpf_patch_insn_data(env, i + delta, insn_buf, cnt); + if (!new_prog) + return -ENOMEM; + + delta += cnt - 1; + env->prog = prog = new_prog; + insn = new_prog->insnsi + i + delta; + goto patch_call_imm; + } + /* BPF_EMIT_CALL() assumptions in some of the map_gen_lookup * and other inlining handlers are currently limited to 64 bit * only. @@ -19541,7 +20095,7 @@ static void free_states(struct bpf_verifier_env *env) } } -static int do_check_common(struct bpf_verifier_env *env, int subprog) +static int do_check_common(struct bpf_verifier_env *env, int subprog, bool is_ex_cb) { bool pop_log = !(env->log.level & BPF_LOG_LEVEL2); struct bpf_verifier_state *state; @@ -19572,7 +20126,7 @@ static int do_check_common(struct bpf_verifier_env *env, int subprog) regs = state->frame[state->curframe]->regs; if (subprog || env->prog->type == BPF_PROG_TYPE_EXT) { - ret = btf_prepare_func_args(env, subprog, regs); + ret = btf_prepare_func_args(env, subprog, regs, is_ex_cb); if (ret) goto out; for (i = BPF_REG_1; i <= BPF_REG_5; i++) { @@ -19588,6 +20142,12 @@ static int do_check_common(struct bpf_verifier_env *env, int subprog) regs[i].id = ++env->id_gen; } } + if (is_ex_cb) { + state->frame[0]->in_exception_callback_fn = true; + env->subprog_info[subprog].is_cb = true; + env->subprog_info[subprog].is_async_cb = true; + env->subprog_info[subprog].is_exception_cb = true; + } } else { /* 1st arg to a function */ regs[BPF_REG_1].type = PTR_TO_CTX; @@ -19652,7 +20212,7 @@ static int do_check_subprogs(struct bpf_verifier_env *env) continue; env->insn_idx = env->subprog_info[i].start; WARN_ON_ONCE(env->insn_idx == 0); - ret = do_check_common(env, i); + ret = do_check_common(env, i, env->exception_callback_subprog == i); if (ret) { return ret; } else if (env->log.level & BPF_LOG_LEVEL) { @@ -19669,7 +20229,7 @@ static int do_check_main(struct bpf_verifier_env *env) int ret; env->insn_idx = 0; - ret = do_check_common(env, 0); + ret = do_check_common(env, 0, false); if (!ret) env->prog->aux->stack_depth = env->subprog_info[0].stack_depth; return ret; @@ -19838,6 +20398,12 @@ int bpf_check_attach_target(struct bpf_verifier_log *log, bpf_log(log, "Subprog %s doesn't exist\n", tname); return -EINVAL; } + if (aux->func && aux->func[subprog]->aux->exception_cb) { + bpf_log(log, + "%s programs cannot attach to exception callback\n", + prog_extension ? "Extension" : "FENTRY/FEXIT"); + return -EINVAL; + } conservative = aux->func_info_aux[subprog].unreliable; if (prog_extension) { if (conservative) { @@ -20265,6 +20831,10 @@ int bpf_check(struct bpf_prog **prog, union bpf_attr *attr, bpfptr_t uattr, __u3 if (!env->explored_states) goto skip_full_check; + ret = check_btf_info_early(env, attr, uattr); + if (ret < 0) + goto skip_full_check; + ret = add_subprog_and_kfunc(env); if (ret < 0) goto skip_full_check; diff --git a/kernel/cgroup/cgroup.c b/kernel/cgroup/cgroup.c index 518725b572..4b9ff41ca6 100644 --- a/kernel/cgroup/cgroup.c +++ b/kernel/cgroup/cgroup.c @@ -207,6 +207,8 @@ static u16 have_exit_callback __read_mostly; static u16 have_release_callback __read_mostly; static u16 have_canfork_callback __read_mostly; +static bool have_favordynmods __ro_after_init = IS_ENABLED(CONFIG_CGROUP_FAVOR_DYNMODS); + /* cgroup namespace for init task */ struct cgroup_namespace init_cgroup_ns = { .ns.count = REFCOUNT_INIT(2), @@ -1350,7 +1352,9 @@ static void cgroup_destroy_root(struct cgroup_root *root) cgroup_root_count--; } - cgroup_favor_dynmods(root, false); + if (!have_favordynmods) + cgroup_favor_dynmods(root, false); + cgroup_exit_root_id(root); cgroup_unlock(); @@ -1719,20 +1723,22 @@ static int css_populate_dir(struct cgroup_subsys_state *css) if (!css->ss) { if (cgroup_on_dfl(cgrp)) { - ret = cgroup_addrm_files(&cgrp->self, cgrp, + ret = cgroup_addrm_files(css, cgrp, cgroup_base_files, true); if (ret < 0) return ret; if (cgroup_psi_enabled()) { - ret = cgroup_addrm_files(&cgrp->self, cgrp, + ret = cgroup_addrm_files(css, cgrp, cgroup_psi_files, true); if (ret < 0) return ret; } } else { - cgroup_addrm_files(css, cgrp, - cgroup1_base_files, true); + ret = cgroup_addrm_files(css, cgrp, + cgroup1_base_files, true); + if (ret < 0) + return ret; } } else { list_for_each_entry(cfts, &css->ss->cfts, node) { @@ -1902,6 +1908,7 @@ enum cgroup2_param { Opt_favordynmods, Opt_memory_localevents, Opt_memory_recursiveprot, + Opt_memory_hugetlb_accounting, nr__cgroup2_params }; @@ -1910,6 +1917,7 @@ static const struct fs_parameter_spec cgroup2_fs_parameters[] = { fsparam_flag("favordynmods", Opt_favordynmods), fsparam_flag("memory_localevents", Opt_memory_localevents), fsparam_flag("memory_recursiveprot", Opt_memory_recursiveprot), + fsparam_flag("memory_hugetlb_accounting", Opt_memory_hugetlb_accounting), {} }; @@ -1936,6 +1944,9 @@ static int cgroup2_parse_param(struct fs_context *fc, struct fs_parameter *param case Opt_memory_recursiveprot: ctx->flags |= CGRP_ROOT_MEMORY_RECURSIVE_PROT; return 0; + case Opt_memory_hugetlb_accounting: + ctx->flags |= CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; + return 0; } return -EINVAL; } @@ -1960,6 +1971,11 @@ static void apply_cgroup_root_flags(unsigned int root_flags) cgrp_dfl_root.flags |= CGRP_ROOT_MEMORY_RECURSIVE_PROT; else cgrp_dfl_root.flags &= ~CGRP_ROOT_MEMORY_RECURSIVE_PROT; + + if (root_flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING) + cgrp_dfl_root.flags |= CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; + else + cgrp_dfl_root.flags &= ~CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING; } } @@ -1973,6 +1989,8 @@ static int cgroup_show_options(struct seq_file *seq, struct kernfs_root *kf_root seq_puts(seq, ",memory_localevents"); if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_RECURSIVE_PROT) seq_puts(seq, ",memory_recursiveprot"); + if (cgrp_dfl_root.flags & CGRP_ROOT_MEMORY_HUGETLB_ACCOUNTING) + seq_puts(seq, ",memory_hugetlb_accounting"); return 0; } @@ -2243,9 +2261,9 @@ static int cgroup_init_fs_context(struct fs_context *fc) fc->user_ns = get_user_ns(ctx->ns->user_ns); fc->global = true; -#ifdef CONFIG_CGROUP_FAVOR_DYNMODS - ctx->flags |= CGRP_ROOT_FAVOR_DYNMODS; -#endif + if (have_favordynmods) + ctx->flags |= CGRP_ROOT_FAVOR_DYNMODS; + return 0; } @@ -4909,9 +4927,11 @@ repeat: void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags, struct css_task_iter *it) { + unsigned long irqflags; + memset(it, 0, sizeof(*it)); - spin_lock_irq(&css_set_lock); + spin_lock_irqsave(&css_set_lock, irqflags); it->ss = css->ss; it->flags = flags; @@ -4925,7 +4945,7 @@ void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags, css_task_iter_advance(it); - spin_unlock_irq(&css_set_lock); + spin_unlock_irqrestore(&css_set_lock, irqflags); } /** @@ -4938,12 +4958,14 @@ void css_task_iter_start(struct cgroup_subsys_state *css, unsigned int flags, */ struct task_struct *css_task_iter_next(struct css_task_iter *it) { + unsigned long irqflags; + if (it->cur_task) { put_task_struct(it->cur_task); it->cur_task = NULL; } - spin_lock_irq(&css_set_lock); + spin_lock_irqsave(&css_set_lock, irqflags); /* @it may be half-advanced by skips, finish advancing */ if (it->flags & CSS_TASK_ITER_SKIPPED) @@ -4956,7 +4978,7 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it) css_task_iter_advance(it); } - spin_unlock_irq(&css_set_lock); + spin_unlock_irqrestore(&css_set_lock, irqflags); return it->cur_task; } @@ -4969,11 +4991,13 @@ struct task_struct *css_task_iter_next(struct css_task_iter *it) */ void css_task_iter_end(struct css_task_iter *it) { + unsigned long irqflags; + if (it->cur_cset) { - spin_lock_irq(&css_set_lock); + spin_lock_irqsave(&css_set_lock, irqflags); list_del(&it->iters_node); put_css_set_locked(it->cur_cset); - spin_unlock_irq(&css_set_lock); + spin_unlock_irqrestore(&css_set_lock, irqflags); } if (it->cur_dcset) @@ -6109,7 +6133,7 @@ int __init cgroup_init(void) if (cgroup1_ssid_disabled(ssid)) pr_info("Disabling %s control group subsystem in v1 mounts\n", - ss->name); + ss->legacy_name); cgrp_dfl_root.subsys_mask |= 1 << ss->id; @@ -6752,6 +6776,12 @@ static int __init enable_cgroup_debug(char *str) } __setup("cgroup_debug", enable_cgroup_debug); +static int __init cgroup_favordynmods_setup(char *str) +{ + return (kstrtobool(str, &have_favordynmods) == 0); +} +__setup("cgroup_favordynmods=", cgroup_favordynmods_setup); + /** * css_tryget_online_from_dir - get corresponding css from a cgroup dentry * @dentry: directory dentry of interest @@ -7038,7 +7068,8 @@ static ssize_t features_show(struct kobject *kobj, struct kobj_attribute *attr, "nsdelegate\n" "favordynmods\n" "memory_localevents\n" - "memory_recursiveprot\n"); + "memory_recursiveprot\n" + "memory_hugetlb_accounting\n"); } static struct kobj_attribute cgroup_features_attr = __ATTR_RO(features); diff --git a/kernel/cgroup/cpuset.c b/kernel/cgroup/cpuset.c index 4749e0c86c..615daaf87f 100644 --- a/kernel/cgroup/cpuset.c +++ b/kernel/cgroup/cpuset.c @@ -75,16 +75,18 @@ enum prs_errcode { PERR_NOCPUS, PERR_HOTPLUG, PERR_CPUSEMPTY, + PERR_HKEEPING, }; static const char * const perr_strings[] = { - [PERR_INVCPUS] = "Invalid cpu list in cpuset.cpus", + [PERR_INVCPUS] = "Invalid cpu list in cpuset.cpus.exclusive", [PERR_INVPARENT] = "Parent is an invalid partition root", [PERR_NOTPART] = "Parent is not a partition root", [PERR_NOTEXCL] = "Cpu list in cpuset.cpus not exclusive", [PERR_NOCPUS] = "Parent unable to distribute cpu downstream", [PERR_HOTPLUG] = "No cpu available due to hotplug", [PERR_CPUSEMPTY] = "cpuset.cpus is empty", + [PERR_HKEEPING] = "partition config conflicts with housekeeping setup", }; struct cpuset { @@ -121,14 +123,23 @@ struct cpuset { nodemask_t effective_mems; /* - * CPUs allocated to child sub-partitions (default hierarchy only) - * - CPUs granted by the parent = effective_cpus U subparts_cpus - * - effective_cpus and subparts_cpus are mutually exclusive. + * Exclusive CPUs dedicated to current cgroup (default hierarchy only) * - * effective_cpus contains only onlined CPUs, but subparts_cpus - * may have offlined ones. + * This exclusive CPUs must be a subset of cpus_allowed. A parent + * cgroup can only grant exclusive CPUs to one of its children. + * + * When the cgroup becomes a valid partition root, effective_xcpus + * defaults to cpus_allowed if not set. The effective_cpus of a valid + * partition root comes solely from its effective_xcpus and some of the + * effective_xcpus may be distributed to sub-partitions below & hence + * excluded from its effective_cpus. + */ + cpumask_var_t effective_xcpus; + + /* + * Exclusive CPUs as requested by the user (default hierarchy only) */ - cpumask_var_t subparts_cpus; + cpumask_var_t exclusive_cpus; /* * This is old Memory Nodes tasks took on. @@ -156,8 +167,8 @@ struct cpuset { /* for custom sched domain */ int relax_domain_level; - /* number of CPUs in subparts_cpus */ - int nr_subparts_cpus; + /* number of valid sub-partitions */ + int nr_subparts; /* partition root state */ int partition_root_state; @@ -183,9 +194,20 @@ struct cpuset { /* Handle for cpuset.cpus.partition */ struct cgroup_file partition_file; + + /* Remote partition silbling list anchored at remote_children */ + struct list_head remote_sibling; }; /* + * Exclusive CPUs distributed out to sub-partitions of top_cpuset + */ +static cpumask_var_t subpartitions_cpus; + +/* List of remote partition root children */ +static struct list_head remote_children; + +/* * Partition root states: * * 0 - member (not a partition root) @@ -312,7 +334,7 @@ static inline int is_partition_invalid(const struct cpuset *cs) */ static inline void make_partition_invalid(struct cpuset *cs) { - if (is_partition_valid(cs)) + if (cs->partition_root_state > 0) cs->partition_root_state = -cs->partition_root_state; } @@ -334,6 +356,7 @@ static struct cpuset top_cpuset = { .flags = ((1 << CS_ONLINE) | (1 << CS_CPU_EXCLUSIVE) | (1 << CS_MEM_EXCLUSIVE)), .partition_root_state = PRS_ROOT, + .remote_sibling = LIST_HEAD_INIT(top_cpuset.remote_sibling), }; /** @@ -469,7 +492,7 @@ static inline bool partition_is_populated(struct cpuset *cs, if (cs->css.cgroup->nr_populated_csets) return true; - if (!excluded_child && !cs->nr_subparts_cpus) + if (!excluded_child && !cs->nr_subparts) return cgroup_is_populated(cs->css.cgroup); rcu_read_lock(); @@ -596,16 +619,18 @@ static int is_cpuset_subset(const struct cpuset *p, const struct cpuset *q) */ static inline int alloc_cpumasks(struct cpuset *cs, struct tmpmasks *tmp) { - cpumask_var_t *pmask1, *pmask2, *pmask3; + cpumask_var_t *pmask1, *pmask2, *pmask3, *pmask4; if (cs) { pmask1 = &cs->cpus_allowed; pmask2 = &cs->effective_cpus; - pmask3 = &cs->subparts_cpus; + pmask3 = &cs->effective_xcpus; + pmask4 = &cs->exclusive_cpus; } else { pmask1 = &tmp->new_cpus; pmask2 = &tmp->addmask; pmask3 = &tmp->delmask; + pmask4 = NULL; } if (!zalloc_cpumask_var(pmask1, GFP_KERNEL)) @@ -617,8 +642,14 @@ static inline int alloc_cpumasks(struct cpuset *cs, struct tmpmasks *tmp) if (!zalloc_cpumask_var(pmask3, GFP_KERNEL)) goto free_two; + if (pmask4 && !zalloc_cpumask_var(pmask4, GFP_KERNEL)) + goto free_three; + + return 0; +free_three: + free_cpumask_var(*pmask3); free_two: free_cpumask_var(*pmask2); free_one: @@ -636,7 +667,8 @@ static inline void free_cpumasks(struct cpuset *cs, struct tmpmasks *tmp) if (cs) { free_cpumask_var(cs->cpus_allowed); free_cpumask_var(cs->effective_cpus); - free_cpumask_var(cs->subparts_cpus); + free_cpumask_var(cs->effective_xcpus); + free_cpumask_var(cs->exclusive_cpus); } if (tmp) { free_cpumask_var(tmp->new_cpus); @@ -664,6 +696,8 @@ static struct cpuset *alloc_trial_cpuset(struct cpuset *cs) cpumask_copy(trial->cpus_allowed, cs->cpus_allowed); cpumask_copy(trial->effective_cpus, cs->effective_cpus); + cpumask_copy(trial->effective_xcpus, cs->effective_xcpus); + cpumask_copy(trial->exclusive_cpus, cs->exclusive_cpus); return trial; } @@ -677,6 +711,28 @@ static inline void free_cpuset(struct cpuset *cs) kfree(cs); } +static inline struct cpumask *fetch_xcpus(struct cpuset *cs) +{ + return !cpumask_empty(cs->exclusive_cpus) ? cs->exclusive_cpus : + cpumask_empty(cs->effective_xcpus) ? cs->cpus_allowed + : cs->effective_xcpus; +} + +/* + * cpusets_are_exclusive() - check if two cpusets are exclusive + * + * Return true if exclusive, false if not + */ +static inline bool cpusets_are_exclusive(struct cpuset *cs1, struct cpuset *cs2) +{ + struct cpumask *xcpus1 = fetch_xcpus(cs1); + struct cpumask *xcpus2 = fetch_xcpus(cs2); + + if (cpumask_intersects(xcpus1, xcpus2)) + return false; + return true; +} + /* * validate_change_legacy() - Validate conditions specific to legacy (v1) * behavior. @@ -776,9 +832,10 @@ static int validate_change(struct cpuset *cur, struct cpuset *trial) ret = -EINVAL; cpuset_for_each_child(c, css, par) { if ((is_cpu_exclusive(trial) || is_cpu_exclusive(c)) && - c != cur && - cpumask_intersects(trial->cpus_allowed, c->cpus_allowed)) - goto out; + c != cur) { + if (!cpusets_are_exclusive(trial, c)) + goto out; + } if ((is_mem_exclusive(trial) || is_mem_exclusive(c)) && c != cur && nodes_intersects(trial->mems_allowed, c->mems_allowed)) @@ -908,7 +965,7 @@ static int generate_sched_domains(cpumask_var_t **domains, csa = NULL; /* Special case for the 99% of systems with one, full, sched domain */ - if (root_load_balance && !top_cpuset.nr_subparts_cpus) { + if (root_load_balance && !top_cpuset.nr_subparts) { ndoms = 1; doms = alloc_sched_domains(ndoms); if (!doms) @@ -1159,7 +1216,7 @@ static void rebuild_sched_domains_locked(void) * should be the same as the active CPUs, so checking only top_cpuset * is enough to detect racing CPU offlines. */ - if (!top_cpuset.nr_subparts_cpus && + if (cpumask_empty(subpartitions_cpus) && !cpumask_equal(top_cpuset.effective_cpus, cpu_active_mask)) return; @@ -1168,7 +1225,7 @@ static void rebuild_sched_domains_locked(void) * root should be only a subset of the active CPUs. Since a CPU in any * partition root could be offlined, all must be checked. */ - if (top_cpuset.nr_subparts_cpus) { + if (top_cpuset.nr_subparts) { rcu_read_lock(); cpuset_for_each_descendant_pre(cs, pos_css, &top_cpuset) { if (!is_partition_valid(cs)) { @@ -1232,7 +1289,7 @@ static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus) */ if (kthread_is_per_cpu(task)) continue; - cpumask_andnot(new_cpus, possible_mask, cs->subparts_cpus); + cpumask_andnot(new_cpus, possible_mask, subpartitions_cpus); } else { cpumask_and(new_cpus, possible_mask, cs->effective_cpus); } @@ -1247,32 +1304,22 @@ static void update_tasks_cpumask(struct cpuset *cs, struct cpumask *new_cpus) * @cs: the cpuset the need to recompute the new effective_cpus mask * @parent: the parent cpuset * - * If the parent has subpartition CPUs, include them in the list of - * allowable CPUs in computing the new effective_cpus mask. Since offlined - * CPUs are not removed from subparts_cpus, we have to use cpu_active_mask - * to mask those out. + * The result is valid only if the given cpuset isn't a partition root. */ static void compute_effective_cpumask(struct cpumask *new_cpus, struct cpuset *cs, struct cpuset *parent) { - if (parent->nr_subparts_cpus && is_partition_valid(cs)) { - cpumask_or(new_cpus, parent->effective_cpus, - parent->subparts_cpus); - cpumask_and(new_cpus, new_cpus, cs->cpus_allowed); - cpumask_and(new_cpus, new_cpus, cpu_active_mask); - } else { - cpumask_and(new_cpus, cs->cpus_allowed, parent->effective_cpus); - } + cpumask_and(new_cpus, cs->cpus_allowed, parent->effective_cpus); } /* - * Commands for update_parent_subparts_cpumask + * Commands for update_parent_effective_cpumask */ -enum subparts_cmd { - partcmd_enable, /* Enable partition root */ - partcmd_disable, /* Disable partition root */ - partcmd_update, /* Update parent's subparts_cpus */ - partcmd_invalidate, /* Make partition invalid */ +enum partition_cmd { + partcmd_enable, /* Enable partition root */ + partcmd_disable, /* Disable partition root */ + partcmd_update, /* Update parent's effective_cpus */ + partcmd_invalidate, /* Make partition invalid */ }; static int update_flag(cpuset_flagbits_t bit, struct cpuset *cs, @@ -1333,8 +1380,296 @@ static void update_partition_sd_lb(struct cpuset *cs, int old_prs) rebuild_sched_domains_locked(); } +/* + * tasks_nocpu_error - Return true if tasks will have no effective_cpus + */ +static bool tasks_nocpu_error(struct cpuset *parent, struct cpuset *cs, + struct cpumask *xcpus) +{ + /* + * A populated partition (cs or parent) can't have empty effective_cpus + */ + return (cpumask_subset(parent->effective_cpus, xcpus) && + partition_is_populated(parent, cs)) || + (!cpumask_intersects(xcpus, cpu_active_mask) && + partition_is_populated(cs, NULL)); +} + +static void reset_partition_data(struct cpuset *cs) +{ + struct cpuset *parent = parent_cs(cs); + + if (!cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) + return; + + lockdep_assert_held(&callback_lock); + + cs->nr_subparts = 0; + if (cpumask_empty(cs->exclusive_cpus)) { + cpumask_clear(cs->effective_xcpus); + if (is_cpu_exclusive(cs)) + clear_bit(CS_CPU_EXCLUSIVE, &cs->flags); + } + if (!cpumask_and(cs->effective_cpus, + parent->effective_cpus, cs->cpus_allowed)) { + cs->use_parent_ecpus = true; + parent->child_ecpus_count++; + cpumask_copy(cs->effective_cpus, parent->effective_cpus); + } +} + +/* + * compute_effective_exclusive_cpumask - compute effective exclusive CPUs + * @cs: cpuset + * @xcpus: effective exclusive CPUs value to be set + * Return: true if xcpus is not empty, false otherwise. + * + * Starting with exclusive_cpus (cpus_allowed if exclusive_cpus is not set), + * it must be a subset of cpus_allowed and parent's effective_xcpus. + */ +static bool compute_effective_exclusive_cpumask(struct cpuset *cs, + struct cpumask *xcpus) +{ + struct cpuset *parent = parent_cs(cs); + + if (!xcpus) + xcpus = cs->effective_xcpus; + + if (!cpumask_empty(cs->exclusive_cpus)) + cpumask_and(xcpus, cs->exclusive_cpus, cs->cpus_allowed); + else + cpumask_copy(xcpus, cs->cpus_allowed); + + return cpumask_and(xcpus, xcpus, parent->effective_xcpus); +} + +static inline bool is_remote_partition(struct cpuset *cs) +{ + return !list_empty(&cs->remote_sibling); +} + +static inline bool is_local_partition(struct cpuset *cs) +{ + return is_partition_valid(cs) && !is_remote_partition(cs); +} + +/* + * remote_partition_enable - Enable current cpuset as a remote partition root + * @cs: the cpuset to update + * @tmp: temparary masks + * Return: 1 if successful, 0 if error + * + * Enable the current cpuset to become a remote partition root taking CPUs + * directly from the top cpuset. cpuset_mutex must be held by the caller. + */ +static int remote_partition_enable(struct cpuset *cs, struct tmpmasks *tmp) +{ + /* + * The user must have sysadmin privilege. + */ + if (!capable(CAP_SYS_ADMIN)) + return 0; + + /* + * The requested exclusive_cpus must not be allocated to other + * partitions and it can't use up all the root's effective_cpus. + * + * Note that if there is any local partition root above it or + * remote partition root underneath it, its exclusive_cpus must + * have overlapped with subpartitions_cpus. + */ + compute_effective_exclusive_cpumask(cs, tmp->new_cpus); + if (cpumask_empty(tmp->new_cpus) || + cpumask_intersects(tmp->new_cpus, subpartitions_cpus) || + cpumask_subset(top_cpuset.effective_cpus, tmp->new_cpus)) + return 0; + + spin_lock_irq(&callback_lock); + cpumask_andnot(top_cpuset.effective_cpus, + top_cpuset.effective_cpus, tmp->new_cpus); + cpumask_or(subpartitions_cpus, + subpartitions_cpus, tmp->new_cpus); + + if (cs->use_parent_ecpus) { + struct cpuset *parent = parent_cs(cs); + + cs->use_parent_ecpus = false; + parent->child_ecpus_count--; + } + list_add(&cs->remote_sibling, &remote_children); + spin_unlock_irq(&callback_lock); + + /* + * Proprogate changes in top_cpuset's effective_cpus down the hierarchy. + */ + update_tasks_cpumask(&top_cpuset, tmp->new_cpus); + update_sibling_cpumasks(&top_cpuset, NULL, tmp); + + return 1; +} + +/* + * remote_partition_disable - Remove current cpuset from remote partition list + * @cs: the cpuset to update + * @tmp: temparary masks + * + * The effective_cpus is also updated. + * + * cpuset_mutex must be held by the caller. + */ +static void remote_partition_disable(struct cpuset *cs, struct tmpmasks *tmp) +{ + compute_effective_exclusive_cpumask(cs, tmp->new_cpus); + WARN_ON_ONCE(!is_remote_partition(cs)); + WARN_ON_ONCE(!cpumask_subset(tmp->new_cpus, subpartitions_cpus)); + + spin_lock_irq(&callback_lock); + cpumask_andnot(subpartitions_cpus, + subpartitions_cpus, tmp->new_cpus); + cpumask_and(tmp->new_cpus, + tmp->new_cpus, cpu_active_mask); + cpumask_or(top_cpuset.effective_cpus, + top_cpuset.effective_cpus, tmp->new_cpus); + list_del_init(&cs->remote_sibling); + cs->partition_root_state = -cs->partition_root_state; + if (!cs->prs_err) + cs->prs_err = PERR_INVCPUS; + reset_partition_data(cs); + spin_unlock_irq(&callback_lock); + + /* + * Proprogate changes in top_cpuset's effective_cpus down the hierarchy. + */ + update_tasks_cpumask(&top_cpuset, tmp->new_cpus); + update_sibling_cpumasks(&top_cpuset, NULL, tmp); +} + +/* + * remote_cpus_update - cpus_exclusive change of remote partition + * @cs: the cpuset to be updated + * @newmask: the new effective_xcpus mask + * @tmp: temparary masks + * + * top_cpuset and subpartitions_cpus will be updated or partition can be + * invalidated. + */ +static void remote_cpus_update(struct cpuset *cs, struct cpumask *newmask, + struct tmpmasks *tmp) +{ + bool adding, deleting; + + if (WARN_ON_ONCE(!is_remote_partition(cs))) + return; + + WARN_ON_ONCE(!cpumask_subset(cs->effective_xcpus, subpartitions_cpus)); + + if (cpumask_empty(newmask)) + goto invalidate; + + adding = cpumask_andnot(tmp->addmask, newmask, cs->effective_xcpus); + deleting = cpumask_andnot(tmp->delmask, cs->effective_xcpus, newmask); + + /* + * Additions of remote CPUs is only allowed if those CPUs are + * not allocated to other partitions and there are effective_cpus + * left in the top cpuset. + */ + if (adding && (!capable(CAP_SYS_ADMIN) || + cpumask_intersects(tmp->addmask, subpartitions_cpus) || + cpumask_subset(top_cpuset.effective_cpus, tmp->addmask))) + goto invalidate; + + spin_lock_irq(&callback_lock); + if (adding) { + cpumask_or(subpartitions_cpus, + subpartitions_cpus, tmp->addmask); + cpumask_andnot(top_cpuset.effective_cpus, + top_cpuset.effective_cpus, tmp->addmask); + } + if (deleting) { + cpumask_andnot(subpartitions_cpus, + subpartitions_cpus, tmp->delmask); + cpumask_and(tmp->delmask, + tmp->delmask, cpu_active_mask); + cpumask_or(top_cpuset.effective_cpus, + top_cpuset.effective_cpus, tmp->delmask); + } + spin_unlock_irq(&callback_lock); + + /* + * Proprogate changes in top_cpuset's effective_cpus down the hierarchy. + */ + update_tasks_cpumask(&top_cpuset, tmp->new_cpus); + update_sibling_cpumasks(&top_cpuset, NULL, tmp); + return; + +invalidate: + remote_partition_disable(cs, tmp); +} + +/* + * remote_partition_check - check if a child remote partition needs update + * @cs: the cpuset to be updated + * @newmask: the new effective_xcpus mask + * @delmask: temporary mask for deletion (not in tmp) + * @tmp: temparary masks + * + * This should be called before the given cs has updated its cpus_allowed + * and/or effective_xcpus. + */ +static void remote_partition_check(struct cpuset *cs, struct cpumask *newmask, + struct cpumask *delmask, struct tmpmasks *tmp) +{ + struct cpuset *child, *next; + int disable_cnt = 0; + + /* + * Compute the effective exclusive CPUs that will be deleted. + */ + if (!cpumask_andnot(delmask, cs->effective_xcpus, newmask) || + !cpumask_intersects(delmask, subpartitions_cpus)) + return; /* No deletion of exclusive CPUs in partitions */ + + /* + * Searching the remote children list to look for those that will + * be impacted by the deletion of exclusive CPUs. + * + * Since a cpuset must be removed from the remote children list + * before it can go offline and holding cpuset_mutex will prevent + * any change in cpuset status. RCU read lock isn't needed. + */ + lockdep_assert_held(&cpuset_mutex); + list_for_each_entry_safe(child, next, &remote_children, remote_sibling) + if (cpumask_intersects(child->effective_cpus, delmask)) { + remote_partition_disable(child, tmp); + disable_cnt++; + } + if (disable_cnt) + rebuild_sched_domains_locked(); +} + +/* + * prstate_housekeeping_conflict - check for partition & housekeeping conflicts + * @prstate: partition root state to be checked + * @new_cpus: cpu mask + * Return: true if there is conflict, false otherwise + * + * CPUs outside of housekeeping_cpumask(HK_TYPE_DOMAIN) can only be used in + * an isolated partition. + */ +static bool prstate_housekeeping_conflict(int prstate, struct cpumask *new_cpus) +{ + const struct cpumask *hk_domain = housekeeping_cpumask(HK_TYPE_DOMAIN); + bool all_in_hk = cpumask_subset(new_cpus, hk_domain); + + if (!all_in_hk && (prstate != PRS_ISOLATED)) + return true; + + return false; +} + /** - * update_parent_subparts_cpumask - update subparts_cpus mask of parent cpuset + * update_parent_effective_cpumask - update effective_cpus mask of parent cpuset * @cs: The cpuset that requests change in partition root state * @cmd: Partition root state change command * @newmask: Optional new cpumask for partcmd_update @@ -1342,21 +1677,20 @@ static void update_partition_sd_lb(struct cpuset *cs, int old_prs) * Return: 0 or a partition root state error code * * For partcmd_enable, the cpuset is being transformed from a non-partition - * root to a partition root. The cpus_allowed mask of the given cpuset will - * be put into parent's subparts_cpus and taken away from parent's + * root to a partition root. The effective_xcpus (cpus_allowed if effective_xcpus + * not set) mask of the given cpuset will be taken away from parent's * effective_cpus. The function will return 0 if all the CPUs listed in - * cpus_allowed can be granted or an error code will be returned. + * effective_xcpus can be granted or an error code will be returned. * * For partcmd_disable, the cpuset is being transformed from a partition - * root back to a non-partition root. Any CPUs in cpus_allowed that are in - * parent's subparts_cpus will be taken away from that cpumask and put back - * into parent's effective_cpus. 0 will always be returned. + * root back to a non-partition root. Any CPUs in effective_xcpus will be + * given back to parent's effective_cpus. 0 will always be returned. * * For partcmd_update, if the optional newmask is specified, the cpu list is - * to be changed from cpus_allowed to newmask. Otherwise, cpus_allowed is + * to be changed from effective_xcpus to newmask. Otherwise, effective_xcpus is * assumed to remain the same. The cpuset should either be a valid or invalid * partition root. The partition root state may change from valid to invalid - * or vice versa. An error code will only be returned if transitioning from + * or vice versa. An error code will be returned if transitioning from * invalid to valid violates the exclusivity rule. * * For partcmd_invalidate, the current partition will be made invalid. @@ -1371,19 +1705,48 @@ static void update_partition_sd_lb(struct cpuset *cs, int old_prs) * check for error and so partition_root_state and prs_error will be updated * directly. */ -static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, - struct cpumask *newmask, - struct tmpmasks *tmp) +static int update_parent_effective_cpumask(struct cpuset *cs, int cmd, + struct cpumask *newmask, + struct tmpmasks *tmp) { struct cpuset *parent = parent_cs(cs); - int adding; /* Moving cpus from effective_cpus to subparts_cpus */ - int deleting; /* Moving cpus from subparts_cpus to effective_cpus */ + int adding; /* Adding cpus to parent's effective_cpus */ + int deleting; /* Deleting cpus from parent's effective_cpus */ int old_prs, new_prs; int part_error = PERR_NONE; /* Partition error? */ + int subparts_delta = 0; + struct cpumask *xcpus; /* cs effective_xcpus */ + bool nocpu; lockdep_assert_held(&cpuset_mutex); /* + * new_prs will only be changed for the partcmd_update and + * partcmd_invalidate commands. + */ + adding = deleting = false; + old_prs = new_prs = cs->partition_root_state; + xcpus = !cpumask_empty(cs->exclusive_cpus) + ? cs->effective_xcpus : cs->cpus_allowed; + + if (cmd == partcmd_invalidate) { + if (is_prs_invalid(old_prs)) + return 0; + + /* + * Make the current partition invalid. + */ + if (is_partition_valid(parent)) + adding = cpumask_and(tmp->addmask, + xcpus, parent->effective_xcpus); + if (old_prs > 0) { + new_prs = -old_prs; + subparts_delta--; + } + goto write_error; + } + + /* * The parent must be a partition root. * The new cpumask, if present, or the current cpus_allowed must * not be empty. @@ -1395,124 +1758,138 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, if (!newmask && cpumask_empty(cs->cpus_allowed)) return PERR_CPUSEMPTY; - /* - * new_prs will only be changed for the partcmd_update and - * partcmd_invalidate commands. - */ - adding = deleting = false; - old_prs = new_prs = cs->partition_root_state; + nocpu = tasks_nocpu_error(parent, cs, xcpus); + if (cmd == partcmd_enable) { /* - * Enabling partition root is not allowed if cpus_allowed - * doesn't overlap parent's cpus_allowed. + * Enabling partition root is not allowed if its + * effective_xcpus is empty or doesn't overlap with + * parent's effective_xcpus. */ - if (!cpumask_intersects(cs->cpus_allowed, parent->cpus_allowed)) + if (cpumask_empty(xcpus) || + !cpumask_intersects(xcpus, parent->effective_xcpus)) return PERR_INVCPUS; + if (prstate_housekeeping_conflict(new_prs, xcpus)) + return PERR_HKEEPING; + /* * A parent can be left with no CPU as long as there is no * task directly associated with the parent partition. */ - if (cpumask_subset(parent->effective_cpus, cs->cpus_allowed) && - partition_is_populated(parent, cs)) + if (nocpu) return PERR_NOCPUS; - cpumask_copy(tmp->addmask, cs->cpus_allowed); - adding = true; + cpumask_copy(tmp->delmask, xcpus); + deleting = true; + subparts_delta++; } else if (cmd == partcmd_disable) { /* - * Need to remove cpus from parent's subparts_cpus for valid - * partition root. + * May need to add cpus to parent's effective_cpus for + * valid partition root. */ - deleting = !is_prs_invalid(old_prs) && - cpumask_and(tmp->delmask, cs->cpus_allowed, - parent->subparts_cpus); - } else if (cmd == partcmd_invalidate) { - if (is_prs_invalid(old_prs)) - return 0; - + adding = !is_prs_invalid(old_prs) && + cpumask_and(tmp->addmask, xcpus, parent->effective_xcpus); + if (adding) + subparts_delta--; + } else if (newmask) { /* - * Make the current partition invalid. It is assumed that - * invalidation is caused by violating cpu exclusivity rule. + * Empty cpumask is not allowed */ - deleting = cpumask_and(tmp->delmask, cs->cpus_allowed, - parent->subparts_cpus); - if (old_prs > 0) { - new_prs = -old_prs; - part_error = PERR_NOTEXCL; + if (cpumask_empty(newmask)) { + part_error = PERR_CPUSEMPTY; + goto write_error; } - } else if (newmask) { + /* * partcmd_update with newmask: * - * Compute add/delete mask to/from subparts_cpus + * Compute add/delete mask to/from effective_cpus + * + * For valid partition: + * addmask = exclusive_cpus & ~newmask + * & parent->effective_xcpus + * delmask = newmask & ~exclusive_cpus + * & parent->effective_xcpus * - * delmask = cpus_allowed & ~newmask & parent->subparts_cpus - * addmask = newmask & parent->cpus_allowed - * & ~parent->subparts_cpus + * For invalid partition: + * delmask = newmask & parent->effective_xcpus */ - cpumask_andnot(tmp->delmask, cs->cpus_allowed, newmask); - deleting = cpumask_and(tmp->delmask, tmp->delmask, - parent->subparts_cpus); + if (is_prs_invalid(old_prs)) { + adding = false; + deleting = cpumask_and(tmp->delmask, + newmask, parent->effective_xcpus); + } else { + cpumask_andnot(tmp->addmask, xcpus, newmask); + adding = cpumask_and(tmp->addmask, tmp->addmask, + parent->effective_xcpus); - cpumask_and(tmp->addmask, newmask, parent->cpus_allowed); - adding = cpumask_andnot(tmp->addmask, tmp->addmask, - parent->subparts_cpus); - /* - * Empty cpumask is not allowed - */ - if (cpumask_empty(newmask)) { - part_error = PERR_CPUSEMPTY; + cpumask_andnot(tmp->delmask, newmask, xcpus); + deleting = cpumask_and(tmp->delmask, tmp->delmask, + parent->effective_xcpus); + } /* * Make partition invalid if parent's effective_cpus could * become empty and there are tasks in the parent. */ - } else if (adding && - cpumask_subset(parent->effective_cpus, tmp->addmask) && - !cpumask_intersects(tmp->delmask, cpu_active_mask) && - partition_is_populated(parent, cs)) { + if (nocpu && (!adding || + !cpumask_intersects(tmp->addmask, cpu_active_mask))) { part_error = PERR_NOCPUS; - adding = false; - deleting = cpumask_and(tmp->delmask, cs->cpus_allowed, - parent->subparts_cpus); + deleting = false; + adding = cpumask_and(tmp->addmask, + xcpus, parent->effective_xcpus); } } else { /* - * partcmd_update w/o newmask: + * partcmd_update w/o newmask + * + * delmask = effective_xcpus & parent->effective_cpus * - * delmask = cpus_allowed & parent->subparts_cpus - * addmask = cpus_allowed & parent->cpus_allowed - * & ~parent->subparts_cpus + * This can be called from: + * 1) update_cpumasks_hier() + * 2) cpuset_hotplug_update_tasks() * - * This gets invoked either due to a hotplug event or from - * update_cpumasks_hier(). This can cause the state of a - * partition root to transition from valid to invalid or vice - * versa. So we still need to compute the addmask and delmask. - - * A partition error happens when: - * 1) Cpuset is valid partition, but parent does not distribute - * out any CPUs. - * 2) Parent has tasks and all its effective CPUs will have - * to be distributed out. + * Check to see if it can be transitioned from valid to + * invalid partition or vice versa. + * + * A partition error happens when parent has tasks and all + * its effective CPUs will have to be distributed out. */ - cpumask_and(tmp->addmask, cs->cpus_allowed, - parent->cpus_allowed); - adding = cpumask_andnot(tmp->addmask, tmp->addmask, - parent->subparts_cpus); - - if ((is_partition_valid(cs) && !parent->nr_subparts_cpus) || - (adding && - cpumask_subset(parent->effective_cpus, tmp->addmask) && - partition_is_populated(parent, cs))) { + WARN_ON_ONCE(!is_partition_valid(parent)); + if (nocpu) { part_error = PERR_NOCPUS; - adding = false; - } + if (is_partition_valid(cs)) + adding = cpumask_and(tmp->addmask, + xcpus, parent->effective_xcpus); + } else if (is_partition_invalid(cs) && + cpumask_subset(xcpus, parent->effective_xcpus)) { + struct cgroup_subsys_state *css; + struct cpuset *child; + bool exclusive = true; - if (part_error && is_partition_valid(cs) && - parent->nr_subparts_cpus) - deleting = cpumask_and(tmp->delmask, cs->cpus_allowed, - parent->subparts_cpus); + /* + * Convert invalid partition to valid has to + * pass the cpu exclusivity test. + */ + rcu_read_lock(); + cpuset_for_each_child(child, css, parent) { + if (child == cs) + continue; + if (!cpusets_are_exclusive(cs, child)) { + exclusive = false; + break; + } + } + rcu_read_unlock(); + if (exclusive) + deleting = cpumask_and(tmp->delmask, + xcpus, parent->effective_cpus); + else + part_error = PERR_NOTEXCL; + } } + +write_error: if (part_error) WRITE_ONCE(cs->prs_err, part_error); @@ -1524,13 +1901,17 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, switch (cs->partition_root_state) { case PRS_ROOT: case PRS_ISOLATED: - if (part_error) + if (part_error) { new_prs = -old_prs; + subparts_delta--; + } break; case PRS_INVALID_ROOT: case PRS_INVALID_ISOLATED: - if (!part_error) + if (!part_error) { new_prs = -old_prs; + subparts_delta++; + } break; } } @@ -1540,9 +1921,11 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, /* * Transitioning between invalid to valid or vice versa may require - * changing CS_CPU_EXCLUSIVE. + * changing CS_CPU_EXCLUSIVE. In the case of partcmd_update, + * validate_change() has already been successfully called and + * CPU lists in cs haven't been updated yet. So defer it to later. */ - if (old_prs != new_prs) { + if ((old_prs != new_prs) && (cmd != partcmd_update)) { int err = update_partition_exclusive(cs, new_prs); if (err) @@ -1550,39 +1933,52 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, } /* - * Change the parent's subparts_cpus. + * Change the parent's effective_cpus & effective_xcpus (top cpuset + * only). + * * Newly added CPUs will be removed from effective_cpus and * newly deleted ones will be added back to effective_cpus. */ spin_lock_irq(&callback_lock); if (adding) { - cpumask_or(parent->subparts_cpus, - parent->subparts_cpus, tmp->addmask); - cpumask_andnot(parent->effective_cpus, - parent->effective_cpus, tmp->addmask); - } - if (deleting) { - cpumask_andnot(parent->subparts_cpus, - parent->subparts_cpus, tmp->delmask); + if (parent == &top_cpuset) + cpumask_andnot(subpartitions_cpus, + subpartitions_cpus, tmp->addmask); /* - * Some of the CPUs in subparts_cpus might have been offlined. + * Some of the CPUs in effective_xcpus might have been offlined. */ - cpumask_and(tmp->delmask, tmp->delmask, cpu_active_mask); cpumask_or(parent->effective_cpus, - parent->effective_cpus, tmp->delmask); + parent->effective_cpus, tmp->addmask); + cpumask_and(parent->effective_cpus, + parent->effective_cpus, cpu_active_mask); + } + if (deleting) { + if (parent == &top_cpuset) + cpumask_or(subpartitions_cpus, + subpartitions_cpus, tmp->delmask); + cpumask_andnot(parent->effective_cpus, + parent->effective_cpus, tmp->delmask); } - parent->nr_subparts_cpus = cpumask_weight(parent->subparts_cpus); + if (is_partition_valid(parent)) { + parent->nr_subparts += subparts_delta; + WARN_ON_ONCE(parent->nr_subparts < 0); + } - if (old_prs != new_prs) + if (old_prs != new_prs) { cs->partition_root_state = new_prs; + if (new_prs <= 0) + cs->nr_subparts = 0; + } spin_unlock_irq(&callback_lock); + if ((old_prs != new_prs) && (cmd == partcmd_update)) + update_partition_exclusive(cs, new_prs); + if (adding || deleting) { update_tasks_cpumask(parent, tmp->addmask); - if (parent->child_ecpus_count) - update_sibling_cpumasks(parent, cs, tmp); + update_sibling_cpumasks(parent, cs, tmp); } /* @@ -1600,6 +1996,73 @@ static int update_parent_subparts_cpumask(struct cpuset *cs, int cmd, return 0; } +/** + * compute_partition_effective_cpumask - compute effective_cpus for partition + * @cs: partition root cpuset + * @new_ecpus: previously computed effective_cpus to be updated + * + * Compute the effective_cpus of a partition root by scanning effective_xcpus + * of child partition roots and excluding their effective_xcpus. + * + * This has the side effect of invalidating valid child partition roots, + * if necessary. Since it is called from either cpuset_hotplug_update_tasks() + * or update_cpumasks_hier() where parent and children are modified + * successively, we don't need to call update_parent_effective_cpumask() + * and the child's effective_cpus will be updated in later iterations. + * + * Note that rcu_read_lock() is assumed to be held. + */ +static void compute_partition_effective_cpumask(struct cpuset *cs, + struct cpumask *new_ecpus) +{ + struct cgroup_subsys_state *css; + struct cpuset *child; + bool populated = partition_is_populated(cs, NULL); + + /* + * Check child partition roots to see if they should be + * invalidated when + * 1) child effective_xcpus not a subset of new + * excluisve_cpus + * 2) All the effective_cpus will be used up and cp + * has tasks + */ + compute_effective_exclusive_cpumask(cs, new_ecpus); + cpumask_and(new_ecpus, new_ecpus, cpu_active_mask); + + rcu_read_lock(); + cpuset_for_each_child(child, css, cs) { + if (!is_partition_valid(child)) + continue; + + child->prs_err = 0; + if (!cpumask_subset(child->effective_xcpus, + cs->effective_xcpus)) + child->prs_err = PERR_INVCPUS; + else if (populated && + cpumask_subset(new_ecpus, child->effective_xcpus)) + child->prs_err = PERR_NOCPUS; + + if (child->prs_err) { + int old_prs = child->partition_root_state; + + /* + * Invalidate child partition + */ + spin_lock_irq(&callback_lock); + make_partition_invalid(child); + cs->nr_subparts--; + child->nr_subparts = 0; + spin_unlock_irq(&callback_lock); + notify_partition_change(child, old_prs); + continue; + } + cpumask_andnot(new_ecpus, new_ecpus, + child->effective_xcpus); + } + rcu_read_unlock(); +} + /* * update_cpumasks_hier() flags */ @@ -1630,9 +2093,44 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp, rcu_read_lock(); cpuset_for_each_descendant_pre(cp, pos_css, cs) { struct cpuset *parent = parent_cs(cp); + bool remote = is_remote_partition(cp); bool update_parent = false; - compute_effective_cpumask(tmp->new_cpus, cp, parent); + /* + * Skip descendent remote partition that acquires CPUs + * directly from top cpuset unless it is cs. + */ + if (remote && (cp != cs)) { + pos_css = css_rightmost_descendant(pos_css); + continue; + } + + /* + * Update effective_xcpus if exclusive_cpus set. + * The case when exclusive_cpus isn't set is handled later. + */ + if (!cpumask_empty(cp->exclusive_cpus) && (cp != cs)) { + spin_lock_irq(&callback_lock); + compute_effective_exclusive_cpumask(cp, NULL); + spin_unlock_irq(&callback_lock); + } + + old_prs = new_prs = cp->partition_root_state; + if (remote || (is_partition_valid(parent) && + is_partition_valid(cp))) + compute_partition_effective_cpumask(cp, tmp->new_cpus); + else + compute_effective_cpumask(tmp->new_cpus, cp, parent); + + /* + * A partition with no effective_cpus is allowed as long as + * there is no task associated with it. Call + * update_parent_effective_cpumask() to check it. + */ + if (is_partition_valid(cp) && cpumask_empty(tmp->new_cpus)) { + update_parent = true; + goto update_parent_effective; + } /* * If it becomes empty, inherit the effective mask of the @@ -1640,11 +2138,7 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp, * it is a partition root that has explicitly distributed * out all its CPUs. */ - if (is_in_v2_mode() && cpumask_empty(tmp->new_cpus)) { - if (is_partition_valid(cp) && - cpumask_equal(cp->cpus_allowed, cp->subparts_cpus)) - goto update_parent_subparts; - + if (is_in_v2_mode() && !remote && cpumask_empty(tmp->new_cpus)) { cpumask_copy(tmp->new_cpus, parent->effective_cpus); if (!cp->use_parent_ecpus) { cp->use_parent_ecpus = true; @@ -1656,6 +2150,9 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp, parent->child_ecpus_count--; } + if (remote) + goto get_css; + /* * Skip the whole subtree if * 1) the cpumask remains the same, @@ -1671,14 +2168,13 @@ static void update_cpumasks_hier(struct cpuset *cs, struct tmpmasks *tmp, continue; } -update_parent_subparts: +update_parent_effective: /* - * update_parent_subparts_cpumask() should have been called + * update_parent_effective_cpumask() should have been called * for cs already in update_cpumask(). We should also call * update_tasks_cpumask() again for tasks in the parent - * cpuset if the parent's subparts_cpus changes. + * cpuset if the parent's effective_cpus changes. */ - old_prs = new_prs = cp->partition_root_state; if ((cp != cs) && old_prs) { switch (parent->partition_root_state) { case PRS_ROOT: @@ -1700,14 +2196,13 @@ update_parent_subparts: break; } } - +get_css: if (!css_tryget_online(&cp->css)) continue; rcu_read_unlock(); if (update_parent) { - update_parent_subparts_cpumask(cp, partcmd_update, NULL, - tmp); + update_parent_effective_cpumask(cp, partcmd_update, NULL, tmp); /* * The cpuset partition_root_state may become * invalid. Capture it. @@ -1716,30 +2211,17 @@ update_parent_subparts: } spin_lock_irq(&callback_lock); - - if (cp->nr_subparts_cpus && !is_partition_valid(cp)) { - /* - * Put all active subparts_cpus back to effective_cpus. - */ - cpumask_or(tmp->new_cpus, tmp->new_cpus, - cp->subparts_cpus); - cpumask_and(tmp->new_cpus, tmp->new_cpus, - cpu_active_mask); - cp->nr_subparts_cpus = 0; - cpumask_clear(cp->subparts_cpus); - } - cpumask_copy(cp->effective_cpus, tmp->new_cpus); - if (cp->nr_subparts_cpus) { - /* - * Make sure that effective_cpus & subparts_cpus - * are mutually exclusive. - */ - cpumask_andnot(cp->effective_cpus, cp->effective_cpus, - cp->subparts_cpus); - } - cp->partition_root_state = new_prs; + /* + * Make sure effective_xcpus is properly set for a valid + * partition root. + */ + if ((new_prs > 0) && cpumask_empty(cp->exclusive_cpus)) + cpumask_and(cp->effective_xcpus, + cp->cpus_allowed, parent->effective_xcpus); + else if (new_prs < 0) + reset_partition_data(cp); spin_unlock_irq(&callback_lock); notify_partition_change(cp, old_prs); @@ -1747,7 +2229,7 @@ update_parent_subparts: WARN_ON(!is_in_v2_mode() && !cpumask_equal(cp->cpus_allowed, cp->effective_cpus)); - update_tasks_cpumask(cp, tmp->new_cpus); + update_tasks_cpumask(cp, cp->effective_cpus); /* * On default hierarchy, inherit the CS_SCHED_LOAD_BALANCE @@ -1800,8 +2282,13 @@ static void update_sibling_cpumasks(struct cpuset *parent, struct cpuset *cs, /* * Check all its siblings and call update_cpumasks_hier() - * if their use_parent_ecpus flag is set in order for them - * to use the right effective_cpus value. + * if their effective_cpus will need to be changed. + * + * With the addition of effective_xcpus which is a subset of + * cpus_allowed. It is possible a change in parent's effective_cpus + * due to a change in a child partition's effective_xcpus will impact + * its siblings even if they do not inherit parent's effective_cpus + * directly. * * The update_cpumasks_hier() function may sleep. So we have to * release the RCU read lock before calling it. HIER_NO_SD_REBUILD @@ -1812,8 +2299,13 @@ static void update_sibling_cpumasks(struct cpuset *parent, struct cpuset *cs, cpuset_for_each_child(sibling, pos_css, parent) { if (sibling == cs) continue; - if (!sibling->use_parent_ecpus) - continue; + if (!sibling->use_parent_ecpus && + !is_partition_valid(sibling)) { + compute_effective_cpumask(tmp->new_cpus, sibling, + parent); + if (cpumask_equal(tmp->new_cpus, sibling->effective_cpus)) + continue; + } if (!css_tryget_online(&sibling->css)) continue; @@ -1836,7 +2328,9 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, { int retval; struct tmpmasks tmp; + struct cpuset *parent = parent_cs(cs); bool invalidate = false; + int hier_flags = 0; int old_prs = cs->partition_root_state; /* top_cpuset.cpus_allowed tracks cpu_online_mask; it's read-only */ @@ -1851,6 +2345,7 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, */ if (!*buf) { cpumask_clear(trialcs->cpus_allowed); + cpumask_clear(trialcs->effective_xcpus); } else { retval = cpulist_parse(buf, trialcs->cpus_allowed); if (retval < 0) @@ -1859,6 +2354,15 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, if (!cpumask_subset(trialcs->cpus_allowed, top_cpuset.cpus_allowed)) return -EINVAL; + + /* + * When exclusive_cpus isn't explicitly set, it is constrainted + * by cpus_allowed and parent's effective_xcpus. Otherwise, + * trialcs->effective_xcpus is used as a temporary cpumask + * for checking validity of the partition root. + */ + if (!cpumask_empty(trialcs->exclusive_cpus) || is_partition_valid(cs)) + compute_effective_exclusive_cpumask(trialcs, NULL); } /* Nothing to do if the cpus didn't change */ @@ -1868,11 +2372,32 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, if (alloc_cpumasks(NULL, &tmp)) return -ENOMEM; + if (old_prs) { + if (is_partition_valid(cs) && + cpumask_empty(trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_INVCPUS; + } else if (prstate_housekeeping_conflict(old_prs, trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_HKEEPING; + } else if (tasks_nocpu_error(parent, cs, trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_NOCPUS; + } + } + + /* + * Check all the descendants in update_cpumasks_hier() if + * effective_xcpus is to be changed. + */ + if (!cpumask_equal(cs->effective_xcpus, trialcs->effective_xcpus)) + hier_flags = HIER_CHECKALL; + retval = validate_change(cs, trialcs); if ((retval == -EINVAL) && cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) { - struct cpuset *cp, *parent; struct cgroup_subsys_state *css; + struct cpuset *cp; /* * The -EINVAL error code indicates that partition sibling @@ -1883,70 +2408,168 @@ static int update_cpumask(struct cpuset *cs, struct cpuset *trialcs, */ invalidate = true; rcu_read_lock(); - parent = parent_cs(cs); - cpuset_for_each_child(cp, css, parent) + cpuset_for_each_child(cp, css, parent) { + struct cpumask *xcpus = fetch_xcpus(trialcs); + if (is_partition_valid(cp) && - cpumask_intersects(trialcs->cpus_allowed, cp->cpus_allowed)) { + cpumask_intersects(xcpus, cp->effective_xcpus)) { rcu_read_unlock(); - update_parent_subparts_cpumask(cp, partcmd_invalidate, NULL, &tmp); + update_parent_effective_cpumask(cp, partcmd_invalidate, NULL, &tmp); rcu_read_lock(); } + } rcu_read_unlock(); retval = 0; } + if (retval < 0) goto out_free; - if (cs->partition_root_state) { - if (invalidate) - update_parent_subparts_cpumask(cs, partcmd_invalidate, - NULL, &tmp); + if (is_partition_valid(cs) || + (is_partition_invalid(cs) && !invalidate)) { + struct cpumask *xcpus = trialcs->effective_xcpus; + + if (cpumask_empty(xcpus) && is_partition_invalid(cs)) + xcpus = trialcs->cpus_allowed; + + /* + * Call remote_cpus_update() to handle valid remote partition + */ + if (is_remote_partition(cs)) + remote_cpus_update(cs, xcpus, &tmp); + else if (invalidate) + update_parent_effective_cpumask(cs, partcmd_invalidate, + NULL, &tmp); else - update_parent_subparts_cpumask(cs, partcmd_update, - trialcs->cpus_allowed, &tmp); + update_parent_effective_cpumask(cs, partcmd_update, + xcpus, &tmp); + } else if (!cpumask_empty(cs->exclusive_cpus)) { + /* + * Use trialcs->effective_cpus as a temp cpumask + */ + remote_partition_check(cs, trialcs->effective_xcpus, + trialcs->effective_cpus, &tmp); } - compute_effective_cpumask(trialcs->effective_cpus, trialcs, - parent_cs(cs)); spin_lock_irq(&callback_lock); cpumask_copy(cs->cpus_allowed, trialcs->cpus_allowed); + cpumask_copy(cs->effective_xcpus, trialcs->effective_xcpus); + if ((old_prs > 0) && !is_partition_valid(cs)) + reset_partition_data(cs); + spin_unlock_irq(&callback_lock); + + /* effective_cpus/effective_xcpus will be updated here */ + update_cpumasks_hier(cs, &tmp, hier_flags); + + /* Update CS_SCHED_LOAD_BALANCE and/or sched_domains, if necessary */ + if (cs->partition_root_state) + update_partition_sd_lb(cs, old_prs); +out_free: + free_cpumasks(NULL, &tmp); + return 0; +} + +/** + * update_exclusive_cpumask - update the exclusive_cpus mask of a cpuset + * @cs: the cpuset to consider + * @trialcs: trial cpuset + * @buf: buffer of cpu numbers written to this cpuset + * + * The tasks' cpumask will be updated if cs is a valid partition root. + */ +static int update_exclusive_cpumask(struct cpuset *cs, struct cpuset *trialcs, + const char *buf) +{ + int retval; + struct tmpmasks tmp; + struct cpuset *parent = parent_cs(cs); + bool invalidate = false; + int hier_flags = 0; + int old_prs = cs->partition_root_state; + + if (!*buf) { + cpumask_clear(trialcs->exclusive_cpus); + cpumask_clear(trialcs->effective_xcpus); + } else { + retval = cpulist_parse(buf, trialcs->exclusive_cpus); + if (retval < 0) + return retval; + if (!is_cpu_exclusive(cs)) + set_bit(CS_CPU_EXCLUSIVE, &trialcs->flags); + } + + /* Nothing to do if the CPUs didn't change */ + if (cpumask_equal(cs->exclusive_cpus, trialcs->exclusive_cpus)) + return 0; + + if (alloc_cpumasks(NULL, &tmp)) + return -ENOMEM; + + if (*buf) + compute_effective_exclusive_cpumask(trialcs, NULL); /* - * Make sure that subparts_cpus, if not empty, is a subset of - * cpus_allowed. Clear subparts_cpus if partition not valid or - * empty effective cpus with tasks. + * Check all the descendants in update_cpumasks_hier() if + * effective_xcpus is to be changed. */ - if (cs->nr_subparts_cpus) { - if (!is_partition_valid(cs) || - (cpumask_subset(trialcs->effective_cpus, cs->subparts_cpus) && - partition_is_populated(cs, NULL))) { - cs->nr_subparts_cpus = 0; - cpumask_clear(cs->subparts_cpus); + if (!cpumask_equal(cs->effective_xcpus, trialcs->effective_xcpus)) + hier_flags = HIER_CHECKALL; + + retval = validate_change(cs, trialcs); + if (retval) + return retval; + + if (old_prs) { + if (cpumask_empty(trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_INVCPUS; + } else if (prstate_housekeeping_conflict(old_prs, trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_HKEEPING; + } else if (tasks_nocpu_error(parent, cs, trialcs->effective_xcpus)) { + invalidate = true; + cs->prs_err = PERR_NOCPUS; + } + + if (is_remote_partition(cs)) { + if (invalidate) + remote_partition_disable(cs, &tmp); + else + remote_cpus_update(cs, trialcs->effective_xcpus, + &tmp); + } else if (invalidate) { + update_parent_effective_cpumask(cs, partcmd_invalidate, + NULL, &tmp); } else { - cpumask_and(cs->subparts_cpus, cs->subparts_cpus, - cs->cpus_allowed); - cs->nr_subparts_cpus = cpumask_weight(cs->subparts_cpus); + update_parent_effective_cpumask(cs, partcmd_update, + trialcs->effective_xcpus, &tmp); } + } else if (!cpumask_empty(trialcs->exclusive_cpus)) { + /* + * Use trialcs->effective_cpus as a temp cpumask + */ + remote_partition_check(cs, trialcs->effective_xcpus, + trialcs->effective_cpus, &tmp); } + spin_lock_irq(&callback_lock); + cpumask_copy(cs->exclusive_cpus, trialcs->exclusive_cpus); + cpumask_copy(cs->effective_xcpus, trialcs->effective_xcpus); + if ((old_prs > 0) && !is_partition_valid(cs)) + reset_partition_data(cs); spin_unlock_irq(&callback_lock); - /* effective_cpus will be updated here */ - update_cpumasks_hier(cs, &tmp, 0); - - if (cs->partition_root_state) { - struct cpuset *parent = parent_cs(cs); - - /* - * For partition root, update the cpumasks of sibling - * cpusets if they use parent's effective_cpus. - */ - if (parent->child_ecpus_count) - update_sibling_cpumasks(parent, cs, &tmp); + /* + * Call update_cpumasks_hier() to update effective_cpus/effective_xcpus + * of the subtree when it is a valid partition root or effective_xcpus + * is updated. + */ + if (is_partition_valid(cs) || hier_flags) + update_cpumasks_hier(cs, &tmp, hier_flags); - /* Update CS_SCHED_LOAD_BALANCE and/or sched_domains */ + /* Update CS_SCHED_LOAD_BALANCE and/or sched_domains, if necessary */ + if (cs->partition_root_state) update_partition_sd_lb(cs, old_prs); - } -out_free: + free_cpumasks(NULL, &tmp); return 0; } @@ -2330,17 +2953,25 @@ static int update_prstate(struct cpuset *cs, int new_prs) return 0; /* - * For a previously invalid partition root, leave it at being - * invalid if new_prs is not "member". + * Treat a previously invalid partition root as if it is a "member". */ - if (new_prs && is_prs_invalid(old_prs)) { - cs->partition_root_state = -new_prs; - return 0; - } + if (new_prs && is_prs_invalid(old_prs)) + old_prs = PRS_MEMBER; if (alloc_cpumasks(NULL, &tmpmask)) return -ENOMEM; + /* + * Setup effective_xcpus if not properly set yet, it will be cleared + * later if partition becomes invalid. + */ + if ((new_prs > 0) && cpumask_empty(cs->exclusive_cpus)) { + spin_lock_irq(&callback_lock); + cpumask_and(cs->effective_xcpus, + cs->cpus_allowed, parent->effective_xcpus); + spin_unlock_irq(&callback_lock); + } + err = update_partition_exclusive(cs, new_prs); if (err) goto out; @@ -2354,8 +2985,14 @@ static int update_prstate(struct cpuset *cs, int new_prs) goto out; } - err = update_parent_subparts_cpumask(cs, partcmd_enable, - NULL, &tmpmask); + err = update_parent_effective_cpumask(cs, partcmd_enable, + NULL, &tmpmask); + /* + * If an attempt to become local partition root fails, + * try to become a remote partition root instead. + */ + if (err && remote_partition_enable(cs, &tmpmask)) + err = 0; } else if (old_prs && new_prs) { /* * A change in load balance state only, no change in cpumasks. @@ -2366,19 +3003,16 @@ static int update_prstate(struct cpuset *cs, int new_prs) * Switching back to member is always allowed even if it * disables child partitions. */ - update_parent_subparts_cpumask(cs, partcmd_disable, NULL, - &tmpmask); + if (is_remote_partition(cs)) + remote_partition_disable(cs, &tmpmask); + else + update_parent_effective_cpumask(cs, partcmd_disable, + NULL, &tmpmask); /* - * If there are child partitions, they will all become invalid. + * Invalidation of child partitions will be done in + * update_cpumasks_hier(). */ - if (unlikely(cs->nr_subparts_cpus)) { - spin_lock_irq(&callback_lock); - cs->nr_subparts_cpus = 0; - cpumask_clear(cs->subparts_cpus); - compute_effective_cpumask(cs->effective_cpus, cs, parent); - spin_unlock_irq(&callback_lock); - } } out: /* @@ -2393,14 +3027,12 @@ out: spin_lock_irq(&callback_lock); cs->partition_root_state = new_prs; WRITE_ONCE(cs->prs_err, err); + if (!is_partition_valid(cs)) + reset_partition_data(cs); spin_unlock_irq(&callback_lock); - /* - * Update child cpusets, if present. - * Force update if switching back to member. - */ - if (!list_empty(&cs->css.children)) - update_cpumasks_hier(cs, &tmpmask, !new_prs ? HIER_CHECKALL : 0); + /* Force update if switching back to member */ + update_cpumasks_hier(cs, &tmpmask, !new_prs ? HIER_CHECKALL : 0); /* Update sched domains and load balance flag */ update_partition_sd_lb(cs, old_prs); @@ -2649,7 +3281,7 @@ static void cpuset_attach_task(struct cpuset *cs, struct task_struct *task) guarantee_online_cpus(task, cpus_attach); else cpumask_andnot(cpus_attach, task_cpu_possible_mask(task), - cs->subparts_cpus); + subpartitions_cpus); /* * can_attach beforehand should guarantee that this doesn't * fail. TODO: have a better way to handle failure here @@ -2752,6 +3384,8 @@ typedef enum { FILE_EFFECTIVE_CPULIST, FILE_EFFECTIVE_MEMLIST, FILE_SUBPARTS_CPULIST, + FILE_EXCLUSIVE_CPULIST, + FILE_EFFECTIVE_XCPULIST, FILE_CPU_EXCLUSIVE, FILE_MEM_EXCLUSIVE, FILE_MEM_HARDWALL, @@ -2889,6 +3523,9 @@ static ssize_t cpuset_write_resmask(struct kernfs_open_file *of, case FILE_CPULIST: retval = update_cpumask(cs, trialcs, buf); break; + case FILE_EXCLUSIVE_CPULIST: + retval = update_exclusive_cpumask(cs, trialcs, buf); + break; case FILE_MEMLIST: retval = update_nodemask(cs, trialcs, buf); break; @@ -2936,8 +3573,14 @@ static int cpuset_common_seq_show(struct seq_file *sf, void *v) case FILE_EFFECTIVE_MEMLIST: seq_printf(sf, "%*pbl\n", nodemask_pr_args(&cs->effective_mems)); break; + case FILE_EXCLUSIVE_CPULIST: + seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->exclusive_cpus)); + break; + case FILE_EFFECTIVE_XCPULIST: + seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->effective_xcpus)); + break; case FILE_SUBPARTS_CPULIST: - seq_printf(sf, "%*pbl\n", cpumask_pr_args(cs->subparts_cpus)); + seq_printf(sf, "%*pbl\n", cpumask_pr_args(subpartitions_cpus)); break; default: ret = -EINVAL; @@ -3210,10 +3853,26 @@ static struct cftype dfl_files[] = { }, { + .name = "cpus.exclusive", + .seq_show = cpuset_common_seq_show, + .write = cpuset_write_resmask, + .max_write_len = (100U + 6 * NR_CPUS), + .private = FILE_EXCLUSIVE_CPULIST, + .flags = CFTYPE_NOT_ON_ROOT, + }, + + { + .name = "cpus.exclusive.effective", + .seq_show = cpuset_common_seq_show, + .private = FILE_EFFECTIVE_XCPULIST, + .flags = CFTYPE_NOT_ON_ROOT, + }, + + { .name = "cpus.subpartitions", .seq_show = cpuset_common_seq_show, .private = FILE_SUBPARTS_CPULIST, - .flags = CFTYPE_DEBUG, + .flags = CFTYPE_ONLY_ON_ROOT | CFTYPE_DEBUG, }, { } /* terminate */ @@ -3251,6 +3910,7 @@ cpuset_css_alloc(struct cgroup_subsys_state *parent_css) nodes_clear(cs->effective_mems); fmeter_init(&cs->fmeter); cs->relax_domain_level = -1; + INIT_LIST_HEAD(&cs->remote_sibling); /* Set CS_MEMORY_MIGRATE for default hierarchy */ if (cgroup_subsys_on_dfl(cpuset_cgrp_subsys)) @@ -3286,6 +3946,11 @@ static int cpuset_css_online(struct cgroup_subsys_state *css) cs->effective_mems = parent->effective_mems; cs->use_parent_ecpus = true; parent->child_ecpus_count++; + /* + * Clear CS_SCHED_LOAD_BALANCE if parent is isolated + */ + if (!is_sched_load_balance(parent)) + clear_bit(CS_SCHED_LOAD_BALANCE, &cs->flags); } /* @@ -3387,6 +4052,7 @@ static void cpuset_bind(struct cgroup_subsys_state *root_css) if (is_in_v2_mode()) { cpumask_copy(top_cpuset.cpus_allowed, cpu_possible_mask); + cpumask_copy(top_cpuset.effective_xcpus, cpu_possible_mask); top_cpuset.mems_allowed = node_possible_map; } else { cpumask_copy(top_cpuset.cpus_allowed, @@ -3525,16 +4191,21 @@ int __init cpuset_init(void) { BUG_ON(!alloc_cpumask_var(&top_cpuset.cpus_allowed, GFP_KERNEL)); BUG_ON(!alloc_cpumask_var(&top_cpuset.effective_cpus, GFP_KERNEL)); - BUG_ON(!zalloc_cpumask_var(&top_cpuset.subparts_cpus, GFP_KERNEL)); + BUG_ON(!alloc_cpumask_var(&top_cpuset.effective_xcpus, GFP_KERNEL)); + BUG_ON(!alloc_cpumask_var(&top_cpuset.exclusive_cpus, GFP_KERNEL)); + BUG_ON(!zalloc_cpumask_var(&subpartitions_cpus, GFP_KERNEL)); cpumask_setall(top_cpuset.cpus_allowed); nodes_setall(top_cpuset.mems_allowed); cpumask_setall(top_cpuset.effective_cpus); + cpumask_setall(top_cpuset.effective_xcpus); + cpumask_setall(top_cpuset.exclusive_cpus); nodes_setall(top_cpuset.effective_mems); fmeter_init(&top_cpuset.fmeter); set_bit(CS_SCHED_LOAD_BALANCE, &top_cpuset.flags); top_cpuset.relax_domain_level = -1; + INIT_LIST_HEAD(&remote_children); BUG_ON(!alloc_cpumask_var(&cpus_attach, GFP_KERNEL)); @@ -3650,6 +4321,7 @@ static void cpuset_hotplug_update_tasks(struct cpuset *cs, struct tmpmasks *tmp) static nodemask_t new_mems; bool cpus_updated; bool mems_updated; + bool remote; struct cpuset *parent; retry: wait_event(cpuset_attach_wq, cs->attach_in_progress == 0); @@ -3669,29 +4341,23 @@ retry: compute_effective_cpumask(&new_cpus, cs, parent); nodes_and(new_mems, cs->mems_allowed, parent->effective_mems); - if (cs->nr_subparts_cpus) - /* - * Make sure that CPUs allocated to child partitions - * do not show up in effective_cpus. - */ - cpumask_andnot(&new_cpus, &new_cpus, cs->subparts_cpus); - if (!tmp || !cs->partition_root_state) goto update_tasks; /* - * In the unlikely event that a partition root has empty - * effective_cpus with tasks, we will have to invalidate child - * partitions, if present, by setting nr_subparts_cpus to 0 to - * reclaim their cpus. + * Compute effective_cpus for valid partition root, may invalidate + * child partition roots if necessary. */ - if (cs->nr_subparts_cpus && is_partition_valid(cs) && - cpumask_empty(&new_cpus) && partition_is_populated(cs, NULL)) { - spin_lock_irq(&callback_lock); - cs->nr_subparts_cpus = 0; - cpumask_clear(cs->subparts_cpus); - spin_unlock_irq(&callback_lock); + remote = is_remote_partition(cs); + if (remote || (is_partition_valid(cs) && is_partition_valid(parent))) + compute_partition_effective_cpumask(cs, &new_cpus); + + if (remote && cpumask_empty(&new_cpus) && + partition_is_populated(cs, NULL)) { + remote_partition_disable(cs, tmp); compute_effective_cpumask(&new_cpus, cs, parent); + remote = false; + cpuset_force_rebuild(); } /* @@ -3701,44 +4367,22 @@ retry: * 2) parent is invalid or doesn't grant any cpus to child * partitions. */ - if (is_partition_valid(cs) && (!parent->nr_subparts_cpus || - (cpumask_empty(&new_cpus) && partition_is_populated(cs, NULL)))) { - int old_prs, parent_prs; - - update_parent_subparts_cpumask(cs, partcmd_disable, NULL, tmp); - if (cs->nr_subparts_cpus) { - spin_lock_irq(&callback_lock); - cs->nr_subparts_cpus = 0; - cpumask_clear(cs->subparts_cpus); - spin_unlock_irq(&callback_lock); - compute_effective_cpumask(&new_cpus, cs, parent); - } - - old_prs = cs->partition_root_state; - parent_prs = parent->partition_root_state; - if (is_partition_valid(cs)) { - spin_lock_irq(&callback_lock); - make_partition_invalid(cs); - spin_unlock_irq(&callback_lock); - if (is_prs_invalid(parent_prs)) - WRITE_ONCE(cs->prs_err, PERR_INVPARENT); - else if (!parent_prs) - WRITE_ONCE(cs->prs_err, PERR_NOTPART); - else - WRITE_ONCE(cs->prs_err, PERR_HOTPLUG); - notify_partition_change(cs, old_prs); - } + if (is_local_partition(cs) && (!is_partition_valid(parent) || + tasks_nocpu_error(parent, cs, &new_cpus))) { + update_parent_effective_cpumask(cs, partcmd_invalidate, NULL, tmp); + compute_effective_cpumask(&new_cpus, cs, parent); cpuset_force_rebuild(); } - /* * On the other hand, an invalid partition root may be transitioned * back to a regular one. */ else if (is_partition_valid(parent) && is_partition_invalid(cs)) { - update_parent_subparts_cpumask(cs, partcmd_update, NULL, tmp); - if (is_partition_valid(cs)) + update_parent_effective_cpumask(cs, partcmd_update, NULL, tmp); + if (is_partition_valid(cs)) { + compute_partition_effective_cpumask(cs, &new_cpus); cpuset_force_rebuild(); + } } update_tasks: @@ -3796,21 +4440,22 @@ static void cpuset_hotplug_workfn(struct work_struct *work) new_mems = node_states[N_MEMORY]; /* - * If subparts_cpus is populated, it is likely that the check below - * will produce a false positive on cpus_updated when the cpu list - * isn't changed. It is extra work, but it is better to be safe. + * If subpartitions_cpus is populated, it is likely that the check + * below will produce a false positive on cpus_updated when the cpu + * list isn't changed. It is extra work, but it is better to be safe. */ - cpus_updated = !cpumask_equal(top_cpuset.effective_cpus, &new_cpus); + cpus_updated = !cpumask_equal(top_cpuset.effective_cpus, &new_cpus) || + !cpumask_empty(subpartitions_cpus); mems_updated = !nodes_equal(top_cpuset.effective_mems, new_mems); /* - * In the rare case that hotplug removes all the cpus in subparts_cpus, - * we assumed that cpus are updated. + * In the rare case that hotplug removes all the cpus in + * subpartitions_cpus, we assumed that cpus are updated. */ - if (!cpus_updated && top_cpuset.nr_subparts_cpus) + if (!cpus_updated && top_cpuset.nr_subparts) cpus_updated = true; - /* synchronize cpus_allowed to cpu_active_mask */ + /* For v1, synchronize cpus_allowed to cpu_active_mask */ if (cpus_updated) { spin_lock_irq(&callback_lock); if (!on_dfl) @@ -3818,17 +4463,16 @@ static void cpuset_hotplug_workfn(struct work_struct *work) /* * Make sure that CPUs allocated to child partitions * do not show up in effective_cpus. If no CPU is left, - * we clear the subparts_cpus & let the child partitions + * we clear the subpartitions_cpus & let the child partitions * fight for the CPUs again. */ - if (top_cpuset.nr_subparts_cpus) { - if (cpumask_subset(&new_cpus, - top_cpuset.subparts_cpus)) { - top_cpuset.nr_subparts_cpus = 0; - cpumask_clear(top_cpuset.subparts_cpus); + if (!cpumask_empty(subpartitions_cpus)) { + if (cpumask_subset(&new_cpus, subpartitions_cpus)) { + top_cpuset.nr_subparts = 0; + cpumask_clear(subpartitions_cpus); } else { cpumask_andnot(&new_cpus, &new_cpus, - top_cpuset.subparts_cpus); + subpartitions_cpus); } } cpumask_copy(top_cpuset.effective_cpus, &new_cpus); @@ -3960,7 +4604,7 @@ void cpuset_cpus_allowed(struct task_struct *tsk, struct cpumask *pmask) * We first exclude cpus allocated to partitions. If there is no * allowable online cpu left, we fall back to all possible cpus. */ - cpumask_andnot(pmask, possible_mask, top_cpuset.subparts_cpus); + cpumask_andnot(pmask, possible_mask, subpartitions_cpus); if (!cpumask_intersects(pmask, cpu_online_mask)) cpumask_copy(pmask, possible_mask); } diff --git a/kernel/cgroup/rstat.c b/kernel/cgroup/rstat.c index d80d7a6081..c0adb7254b 100644 --- a/kernel/cgroup/rstat.c +++ b/kernel/cgroup/rstat.c @@ -156,19 +156,16 @@ static struct cgroup *cgroup_rstat_cpu_pop_updated(struct cgroup *pos, * optimize away the callsite. Therefore, __weak is needed to ensure that the * call is still emitted, by telling the compiler that we don't know what the * function might eventually be. - * - * __diag_* below are needed to dismiss the missing prototype warning. */ -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "kfuncs which will be used in BPF programs"); + +__bpf_hook_start(); __weak noinline void bpf_rstat_flush(struct cgroup *cgrp, struct cgroup *parent, int cpu) { } -__diag_pop(); +__bpf_hook_end(); /* see cgroup_rstat_flush() */ static void cgroup_rstat_flush_locked(struct cgroup *cgrp) diff --git a/kernel/configs/hardening.config b/kernel/configs/hardening.config new file mode 100644 index 0000000000..95a400f042 --- /dev/null +++ b/kernel/configs/hardening.config @@ -0,0 +1,98 @@ +# Help: Basic kernel hardening options +# +# These are considered the basic kernel hardening, self-protection, and +# attack surface reduction options. They are expected to have low (or +# no) performance impact on most workloads, and have a reasonable level +# of legacy API removals. + +# Make sure reporting of various hardening actions is possible. +CONFIG_BUG=y + +# Basic kernel memory permission enforcement. +CONFIG_STRICT_KERNEL_RWX=y +CONFIG_STRICT_MODULE_RWX=y +CONFIG_VMAP_STACK=y + +# Kernel image and memory ASLR. +CONFIG_RANDOMIZE_BASE=y +CONFIG_RANDOMIZE_MEMORY=y + +# Randomize allocator freelists, harden metadata. +CONFIG_SLAB_FREELIST_RANDOM=y +CONFIG_SLAB_FREELIST_HARDENED=y +CONFIG_SHUFFLE_PAGE_ALLOCATOR=y +CONFIG_RANDOM_KMALLOC_CACHES=y + +# Randomize kernel stack offset on syscall entry. +CONFIG_RANDOMIZE_KSTACK_OFFSET_DEFAULT=y + +# Basic stack frame overflow protection. +CONFIG_STACKPROTECTOR=y +CONFIG_STACKPROTECTOR_STRONG=y + +# Basic buffer length bounds checking. +CONFIG_HARDENED_USERCOPY=y +CONFIG_FORTIFY_SOURCE=y + +# Basic array index bounds checking. +CONFIG_UBSAN=y +CONFIG_UBSAN_TRAP=y +CONFIG_UBSAN_BOUNDS=y +# CONFIG_UBSAN_SHIFT is not set +# CONFIG_UBSAN_DIV_ZERO +# CONFIG_UBSAN_UNREACHABLE +# CONFIG_UBSAN_BOOL +# CONFIG_UBSAN_ENUM +# CONFIG_UBSAN_ALIGNMENT +CONFIG_UBSAN_SANITIZE_ALL=y + +# Linked list integrity checking. +CONFIG_LIST_HARDENED=y + +# Initialize all heap variables to zero on allocation. +CONFIG_INIT_ON_ALLOC_DEFAULT_ON=y + +# Initialize all stack variables to zero on function entry. +CONFIG_INIT_STACK_ALL_ZERO=y + +# Wipe RAM at reboot via EFI. For more details, see: +# https://trustedcomputinggroup.org/resource/pc-client-work-group-platform-reset-attack-mitigation-specification/ +# https://bugzilla.redhat.com/show_bug.cgi?id=1532058 +CONFIG_RESET_ATTACK_MITIGATION=y + +# Disable DMA between EFI hand-off and the kernel's IOMMU setup. +CONFIG_EFI_DISABLE_PCI_DMA=y + +# Force IOMMU TLB invalidation so devices will never be able to access stale +# data content. +CONFIG_IOMMU_SUPPORT=y +CONFIG_IOMMU_DEFAULT_DMA_STRICT=y + +# Do not allow direct physical memory access to non-device memory. +CONFIG_STRICT_DEVMEM=y +CONFIG_IO_STRICT_DEVMEM=y + +# Provide userspace with seccomp BPF API for syscall attack surface reduction. +CONFIG_SECCOMP=y +CONFIG_SECCOMP_FILTER=y + +# Provides some protections against SYN flooding. +CONFIG_SYN_COOKIES=y + +# Attack surface reduction: do not autoload TTY line disciplines. +# CONFIG_LDISC_AUTOLOAD is not set + +# Dangerous; enabling this disables userspace brk ASLR. +# CONFIG_COMPAT_BRK is not set + +# Dangerous; exposes kernel text image layout. +# CONFIG_PROC_KCORE is not set + +# Dangerous; enabling this disables userspace VDSO ASLR. +# CONFIG_COMPAT_VDSO is not set + +# Attack surface reduction: Use the modern PTY interface (devpts) only. +# CONFIG_LEGACY_PTYS is not set + +# Attack surface reduction: Use only modesetting video drivers. +# CONFIG_DRM_LEGACY is not set diff --git a/kernel/cpu.c b/kernel/cpu.c index 72e0f5380b..a86972a919 100644 --- a/kernel/cpu.c +++ b/kernel/cpu.c @@ -1380,7 +1380,14 @@ static int takedown_cpu(unsigned int cpu) cpuhp_bp_sync_dead(cpu); tick_cleanup_dead_cpu(cpu); + + /* + * Callbacks must be re-integrated right away to the RCU state machine. + * Otherwise an RCU callback could block a further teardown function + * waiting for its completion. + */ rcutree_migrate_callbacks(cpu); + return 0; } @@ -1396,10 +1403,10 @@ void cpuhp_report_idle_dead(void) struct cpuhp_cpu_state *st = this_cpu_ptr(&cpuhp_state); BUG_ON(st->state != CPUHP_AP_OFFLINE); - rcu_report_dead(smp_processor_id()); + rcutree_report_cpu_dead(); st->state = CPUHP_AP_IDLE_DEAD; /* - * We cannot call complete after rcu_report_dead() so we delegate it + * We cannot call complete after rcutree_report_cpu_dead() so we delegate it * to an online cpu. */ smp_call_function_single(cpumask_first(cpu_online_mask), @@ -1628,7 +1635,7 @@ void notify_cpu_starting(unsigned int cpu) struct cpuhp_cpu_state *st = per_cpu_ptr(&cpuhp_state, cpu); enum cpuhp_state target = min((int)st->target, CPUHP_AP_ONLINE); - rcu_cpu_starting(cpu); /* Enables RCU usage on this CPU. */ + rcutree_report_cpu_starting(cpu); /* Enables RCU usage on this CPU. */ cpumask_set_cpu(cpu, &cpus_booted_once_mask); /* @@ -1736,9 +1743,6 @@ static int cpu_up(unsigned int cpu, enum cpuhp_state target) if (!cpu_possible(cpu)) { pr_err("can't online cpu %d because it is not configured as may-hotadd at boot time\n", cpu); -#if defined(CONFIG_IA64) - pr_err("please check additional_cpus= boot parameter\n"); -#endif return -EINVAL; } diff --git a/kernel/crash_core.c b/kernel/crash_core.c index 2f675ef045..755d8d4ef5 100644 --- a/kernel/crash_core.c +++ b/kernel/crash_core.c @@ -5,7 +5,6 @@ */ #include <linux/buildid.h> -#include <linux/crash_core.h> #include <linux/init.h> #include <linux/utsname.h> #include <linux/vmalloc.h> @@ -13,6 +12,9 @@ #include <linux/kexec.h> #include <linux/memory.h> #include <linux/cpuhotplug.h> +#include <linux/memblock.h> +#include <linux/kexec.h> +#include <linux/kmemleak.h> #include <asm/page.h> #include <asm/sections.h> @@ -33,6 +35,22 @@ u32 *vmcoreinfo_note; /* trusted vmcoreinfo, e.g. we can make a copy in the crash memory */ static unsigned char *vmcoreinfo_data_safecopy; +/* Location of the reserved area for the crash kernel */ +struct resource crashk_res = { + .name = "Crash kernel", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, + .desc = IORES_DESC_CRASH_KERNEL +}; +struct resource crashk_low_res = { + .name = "Crash kernel", + .start = 0, + .end = 0, + .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, + .desc = IORES_DESC_CRASH_KERNEL +}; + /* * parsing the "crashkernel" commandline * @@ -181,7 +199,7 @@ static __initdata char *suffix_tbl[] = { * It returns 0 on success and -EINVAL on failure. */ static int __init parse_crashkernel_suffix(char *cmdline, - unsigned long long *crash_size, + unsigned long long *crash_size, const char *suffix) { char *cur = cmdline; @@ -248,11 +266,11 @@ static int __init __parse_crashkernel(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, unsigned long long *crash_base, - const char *name, const char *suffix) { - char *first_colon, *first_space; - char *ck_cmdline; + char *first_colon, *first_space; + char *ck_cmdline; + char *name = "crashkernel="; BUG_ON(!crash_size || !crash_base); *crash_size = 0; @@ -283,32 +301,53 @@ static int __init __parse_crashkernel(char *cmdline, /* * That function is the entry point for command line parsing and should be * called from the arch-specific code. + * + * If crashkernel=,high|low is supported on architecture, non-NULL values + * should be passed to parameters 'low_size' and 'high'. */ int __init parse_crashkernel(char *cmdline, unsigned long long system_ram, unsigned long long *crash_size, - unsigned long long *crash_base) + unsigned long long *crash_base, + unsigned long long *low_size, + bool *high) { - return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, - "crashkernel=", NULL); -} + int ret; -int __init parse_crashkernel_high(char *cmdline, - unsigned long long system_ram, - unsigned long long *crash_size, - unsigned long long *crash_base) -{ - return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, - "crashkernel=", suffix_tbl[SUFFIX_HIGH]); -} + /* crashkernel=X[@offset] */ + ret = __parse_crashkernel(cmdline, system_ram, crash_size, + crash_base, NULL); +#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION + /* + * If non-NULL 'high' passed in and no normal crashkernel + * setting detected, try parsing crashkernel=,high|low. + */ + if (high && ret == -ENOENT) { + ret = __parse_crashkernel(cmdline, 0, crash_size, + crash_base, suffix_tbl[SUFFIX_HIGH]); + if (ret || !*crash_size) + return -EINVAL; -int __init parse_crashkernel_low(char *cmdline, - unsigned long long system_ram, - unsigned long long *crash_size, - unsigned long long *crash_base) -{ - return __parse_crashkernel(cmdline, system_ram, crash_size, crash_base, - "crashkernel=", suffix_tbl[SUFFIX_LOW]); + /* + * crashkernel=Y,low can be specified or not, but invalid value + * is not allowed. + */ + ret = __parse_crashkernel(cmdline, 0, low_size, + crash_base, suffix_tbl[SUFFIX_LOW]); + if (ret == -ENOENT) { + *low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; + ret = 0; + } else if (ret) { + return ret; + } + + *high = true; + } +#endif + if (!*crash_size) + ret = -EINVAL; + + return ret; } /* @@ -321,6 +360,119 @@ static int __init parse_crashkernel_dummy(char *arg) } early_param("crashkernel", parse_crashkernel_dummy); +#ifdef CONFIG_ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION +static int __init reserve_crashkernel_low(unsigned long long low_size) +{ +#ifdef CONFIG_64BIT + unsigned long long low_base; + + low_base = memblock_phys_alloc_range(low_size, CRASH_ALIGN, 0, CRASH_ADDR_LOW_MAX); + if (!low_base) { + pr_err("cannot allocate crashkernel low memory (size:0x%llx).\n", low_size); + return -ENOMEM; + } + + pr_info("crashkernel low memory reserved: 0x%08llx - 0x%08llx (%lld MB)\n", + low_base, low_base + low_size, low_size >> 20); + + crashk_low_res.start = low_base; + crashk_low_res.end = low_base + low_size - 1; +#endif + return 0; +} + +void __init reserve_crashkernel_generic(char *cmdline, + unsigned long long crash_size, + unsigned long long crash_base, + unsigned long long crash_low_size, + bool high) +{ + unsigned long long search_end = CRASH_ADDR_LOW_MAX, search_base = 0; + bool fixed_base = false; + + /* User specifies base address explicitly. */ + if (crash_base) { + fixed_base = true; + search_base = crash_base; + search_end = crash_base + crash_size; + } else if (high) { + search_base = CRASH_ADDR_LOW_MAX; + search_end = CRASH_ADDR_HIGH_MAX; + } + +retry: + crash_base = memblock_phys_alloc_range(crash_size, CRASH_ALIGN, + search_base, search_end); + if (!crash_base) { + /* + * For crashkernel=size[KMG]@offset[KMG], print out failure + * message if can't reserve the specified region. + */ + if (fixed_base) { + pr_warn("crashkernel reservation failed - memory is in use.\n"); + return; + } + + /* + * For crashkernel=size[KMG], if the first attempt was for + * low memory, fall back to high memory, the minimum required + * low memory will be reserved later. + */ + if (!high && search_end == CRASH_ADDR_LOW_MAX) { + search_end = CRASH_ADDR_HIGH_MAX; + search_base = CRASH_ADDR_LOW_MAX; + crash_low_size = DEFAULT_CRASH_KERNEL_LOW_SIZE; + goto retry; + } + + /* + * For crashkernel=size[KMG],high, if the first attempt was + * for high memory, fall back to low memory. + */ + if (high && search_end == CRASH_ADDR_HIGH_MAX) { + search_end = CRASH_ADDR_LOW_MAX; + search_base = 0; + goto retry; + } + pr_warn("cannot allocate crashkernel (size:0x%llx)\n", + crash_size); + return; + } + + if ((crash_base >= CRASH_ADDR_LOW_MAX) && + crash_low_size && reserve_crashkernel_low(crash_low_size)) { + memblock_phys_free(crash_base, crash_size); + return; + } + + pr_info("crashkernel reserved: 0x%016llx - 0x%016llx (%lld MB)\n", + crash_base, crash_base + crash_size, crash_size >> 20); + + /* + * The crashkernel memory will be removed from the kernel linear + * map. Inform kmemleak so that it won't try to access it. + */ + kmemleak_ignore_phys(crash_base); + if (crashk_low_res.end) + kmemleak_ignore_phys(crashk_low_res.start); + + crashk_res.start = crash_base; + crashk_res.end = crash_base + crash_size - 1; +} + +static __init int insert_crashkernel_resources(void) +{ + if (crashk_res.start < crashk_res.end) + insert_resource(&iomem_resource, &crashk_res); + + if (crashk_low_res.start < crashk_low_res.end) + insert_resource(&iomem_resource, &crashk_low_res); + + return 0; +} +early_initcall(insert_crashkernel_resources); +#endif + int crash_prepare_elf64_headers(struct crash_mem *mem, int need_kernel_map, void **addr, unsigned long *sz) { diff --git a/kernel/cred.c b/kernel/cred.c index 64404d51c0..c033a201c8 100644 --- a/kernel/cred.c +++ b/kernel/cred.c @@ -36,7 +36,7 @@ do { \ static struct kmem_cache *cred_jar; /* init to 2 - one for init_task, one to ensure it is never freed */ -static struct group_info init_groups = { .usage = ATOMIC_INIT(2) }; +static struct group_info init_groups = { .usage = REFCOUNT_INIT(2) }; /* * The initial credentials for the initial task @@ -116,18 +116,23 @@ EXPORT_SYMBOL(__put_cred); */ void exit_creds(struct task_struct *tsk) { - struct cred *cred; + struct cred *real_cred, *cred; kdebug("exit_creds(%u,%p,%p,{%ld})", tsk->pid, tsk->real_cred, tsk->cred, atomic_long_read(&tsk->cred->usage)); - cred = (struct cred *) tsk->real_cred; + real_cred = (struct cred *) tsk->real_cred; tsk->real_cred = NULL; - put_cred(cred); cred = (struct cred *) tsk->cred; tsk->cred = NULL; - put_cred(cred); + + if (real_cred == cred) { + put_cred_many(cred, 2); + } else { + put_cred(real_cred); + put_cred(cred); + } #ifdef CONFIG_KEYS_REQUEST_CACHE key_put(tsk->cached_requested_key); @@ -297,8 +302,7 @@ int copy_creds(struct task_struct *p, unsigned long clone_flags) #endif clone_flags & CLONE_THREAD ) { - p->real_cred = get_cred(p->cred); - get_cred(p->cred); + p->real_cred = get_cred_many(p->cred, 2); kdebug("share_creds(%p{%ld})", p->cred, atomic_long_read(&p->cred->usage)); inc_rlimit_ucounts(task_ucounts(p), UCOUNT_RLIMIT_NPROC, 1); @@ -450,8 +454,7 @@ int commit_creds(struct cred *new) proc_id_connector(task, PROC_EVENT_GID); /* release the old obj and subj refs both */ - put_cred(old); - put_cred(old); + put_cred_many(old, 2); return 0; } EXPORT_SYMBOL(commit_creds); diff --git a/kernel/debug/kdb/kdb_main.c b/kernel/debug/kdb/kdb_main.c index 35aa2e98a9..d05066cb40 100644 --- a/kernel/debug/kdb/kdb_main.c +++ b/kernel/debug/kdb/kdb_main.c @@ -272,11 +272,10 @@ char *kdbgetenv(const char *match) * kdballocenv - This function is used to allocate bytes for * environment entries. * Parameters: - * match A character string representing a numeric value - * Outputs: - * *value the unsigned long representation of the env variable 'match' + * bytes The number of bytes to allocate in the static buffer. * Returns: - * Zero on success, a kdb diagnostic on failure. + * A pointer to the allocated space in the buffer on success. + * NULL if bytes > size available in the envbuffer. * Remarks: * We use a static environment buffer (envbuffer) to hold the values * of dynamically generated environment variables (see kdb_set). Buffer diff --git a/kernel/dma/Kconfig b/kernel/dma/Kconfig index f488997b07..d62f5957f3 100644 --- a/kernel/dma/Kconfig +++ b/kernel/dma/Kconfig @@ -135,6 +135,8 @@ config DMA_COHERENT_POOL config DMA_GLOBAL_POOL select DMA_DECLARE_COHERENT + depends on !ARCH_HAS_DMA_SET_UNCACHED + depends on !DMA_DIRECT_REMAP bool config DMA_DIRECT_REMAP @@ -142,6 +144,15 @@ config DMA_DIRECT_REMAP select DMA_COHERENT_POOL select DMA_NONCOHERENT_MMAP +# +# Fallback to arch code for DMA allocations. This should eventually go away. +# +config ARCH_HAS_DMA_ALLOC + depends on !ARCH_HAS_DMA_SET_UNCACHED + depends on !DMA_DIRECT_REMAP + depends on !DMA_GLOBAL_POOL + bool + config DMA_CMA bool "DMA Contiguous Memory Allocator" depends on HAVE_DMA_CONTIGUOUS && CMA diff --git a/kernel/dma/debug.c b/kernel/dma/debug.c index 06366acd27..3de494375b 100644 --- a/kernel/dma/debug.c +++ b/kernel/dma/debug.c @@ -139,7 +139,7 @@ static const char *const maperr2str[] = { static const char *type2name[] = { [dma_debug_single] = "single", - [dma_debug_sg] = "scather-gather", + [dma_debug_sg] = "scatter-gather", [dma_debug_coherent] = "coherent", [dma_debug_resource] = "resource", }; diff --git a/kernel/dma/direct.c b/kernel/dma/direct.c index 9596ae1aa0..73c9581578 100644 --- a/kernel/dma/direct.c +++ b/kernel/dma/direct.c @@ -220,13 +220,7 @@ void *dma_direct_alloc(struct device *dev, size_t size, return dma_direct_alloc_no_mapping(dev, size, dma_handle, gfp); if (!dev_is_dma_coherent(dev)) { - /* - * Fallback to the arch handler if it exists. This should - * eventually go away. - */ - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && - !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - !IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_ALLOC) && !is_swiotlb_for_alloc(dev)) return arch_dma_alloc(dev, size, dma_handle, gfp, attrs); @@ -240,27 +234,24 @@ void *dma_direct_alloc(struct device *dev, size_t size, dma_handle); /* - * Otherwise remap if the architecture is asking for it. But - * given that remapping memory is a blocking operation we'll - * instead have to dip into the atomic pools. + * Otherwise we require the architecture to either be able to + * mark arbitrary parts of the kernel direct mapping uncached, + * or remapped it uncached. */ + set_uncached = IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED); remap = IS_ENABLED(CONFIG_DMA_DIRECT_REMAP); - if (remap) { - if (dma_direct_use_pool(dev, gfp)) - return dma_direct_alloc_from_pool(dev, size, - dma_handle, gfp); - } else { - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED)) - return NULL; - set_uncached = true; + if (!set_uncached && !remap) { + pr_warn_once("coherent DMA allocations not supported on this platform.\n"); + return NULL; } } /* - * Decrypting memory may block, so allocate the memory from the atomic - * pools if we can't block. + * Remapping or decrypting memory may block, allocate the memory from + * the atomic pools instead if we aren't allowed block. */ - if (force_dma_unencrypted(dev) && dma_direct_use_pool(dev, gfp)) + if ((remap || force_dma_unencrypted(dev)) && + dma_direct_use_pool(dev, gfp)) return dma_direct_alloc_from_pool(dev, size, dma_handle, gfp); /* we always manually zero the memory once we are done */ @@ -330,9 +321,7 @@ void dma_direct_free(struct device *dev, size_t size, return; } - if (!IS_ENABLED(CONFIG_ARCH_HAS_DMA_SET_UNCACHED) && - !IS_ENABLED(CONFIG_DMA_DIRECT_REMAP) && - !IS_ENABLED(CONFIG_DMA_GLOBAL_POOL) && + if (IS_ENABLED(CONFIG_ARCH_HAS_DMA_ALLOC) && !dev_is_dma_coherent(dev) && !is_swiotlb_for_alloc(dev)) { arch_dma_free(dev, size, cpu_addr, dma_addr, attrs); @@ -598,6 +587,46 @@ int dma_direct_supported(struct device *dev, u64 mask) return mask >= phys_to_dma_unencrypted(dev, min_mask); } +/* + * To check whether all ram resource ranges are covered by dma range map + * Returns 0 when further check is needed + * Returns 1 if there is some RAM range can't be covered by dma_range_map + */ +static int check_ram_in_range_map(unsigned long start_pfn, + unsigned long nr_pages, void *data) +{ + unsigned long end_pfn = start_pfn + nr_pages; + const struct bus_dma_region *bdr = NULL; + const struct bus_dma_region *m; + struct device *dev = data; + + while (start_pfn < end_pfn) { + for (m = dev->dma_range_map; PFN_DOWN(m->size); m++) { + unsigned long cpu_start_pfn = PFN_DOWN(m->cpu_start); + + if (start_pfn >= cpu_start_pfn && + start_pfn - cpu_start_pfn < PFN_DOWN(m->size)) { + bdr = m; + break; + } + } + if (!bdr) + return 1; + + start_pfn = PFN_DOWN(bdr->cpu_start) + PFN_DOWN(bdr->size); + } + + return 0; +} + +bool dma_direct_all_ram_mapped(struct device *dev) +{ + if (!dev->dma_range_map) + return true; + return !walk_system_ram_range(0, PFN_DOWN(ULONG_MAX) + 1, dev, + check_ram_in_range_map); +} + size_t dma_direct_max_mapping_size(struct device *dev) { /* If SWIOTLB is active, use its maximum mapping size */ diff --git a/kernel/dma/direct.h b/kernel/dma/direct.h index 97ec892ea0..18d346118f 100644 --- a/kernel/dma/direct.h +++ b/kernel/dma/direct.h @@ -20,6 +20,7 @@ int dma_direct_mmap(struct device *dev, struct vm_area_struct *vma, bool dma_direct_need_sync(struct device *dev, dma_addr_t dma_addr); int dma_direct_map_sg(struct device *dev, struct scatterlist *sgl, int nents, enum dma_data_direction dir, unsigned long attrs); +bool dma_direct_all_ram_mapped(struct device *dev); size_t dma_direct_max_mapping_size(struct device *dev); #if defined(CONFIG_ARCH_HAS_SYNC_DMA_FOR_DEVICE) || \ diff --git a/kernel/dma/mapping.c b/kernel/dma/mapping.c index e323ca48f7..58db8fd704 100644 --- a/kernel/dma/mapping.c +++ b/kernel/dma/mapping.c @@ -793,6 +793,28 @@ int dma_set_coherent_mask(struct device *dev, u64 mask) } EXPORT_SYMBOL(dma_set_coherent_mask); +/** + * dma_addressing_limited - return if the device is addressing limited + * @dev: device to check + * + * Return %true if the devices DMA mask is too small to address all memory in + * the system, else %false. Lack of addressing bits is the prime reason for + * bounce buffering, but might not be the only one. + */ +bool dma_addressing_limited(struct device *dev) +{ + const struct dma_map_ops *ops = get_dma_ops(dev); + + if (min_not_zero(dma_get_mask(dev), dev->bus_dma_limit) < + dma_get_required_mask(dev)) + return true; + + if (unlikely(ops)) + return false; + return !dma_direct_all_ram_mapped(dev); +} +EXPORT_SYMBOL_GPL(dma_addressing_limited); + size_t dma_max_mapping_size(struct device *dev) { const struct dma_map_ops *ops = get_dma_ops(dev); diff --git a/kernel/dma/swiotlb.c b/kernel/dma/swiotlb.c index 2048194a03..33d942615b 100644 --- a/kernel/dma/swiotlb.c +++ b/kernel/dma/swiotlb.c @@ -1309,11 +1309,13 @@ phys_addr_t swiotlb_tbl_map_single(struct device *dev, phys_addr_t orig_addr, pool->slots[index + i].orig_addr = slot_addr(orig_addr, i); tlb_addr = slot_addr(pool->start, index) + offset; /* - * When dir == DMA_FROM_DEVICE we could omit the copy from the orig - * to the tlb buffer, if we knew for sure the device will - * overwrite the entire current content. But we don't. Thus - * unconditional bounce may prevent leaking swiotlb content (i.e. - * kernel memory) to user-space. + * When the device is writing memory, i.e. dir == DMA_FROM_DEVICE, copy + * the original buffer to the TLB buffer before initiating DMA in order + * to preserve the original's data if the device does a partial write, + * i.e. if the device doesn't overwrite the entire buffer. Preserving + * the original data, even if it's garbage, is necessary to match + * hardware behavior. Use of swiotlb is supposed to be transparent, + * i.e. swiotlb must not corrupt memory by clobbering unwritten bytes. */ swiotlb_bounce(dev, tlb_addr, mapping_size, DMA_TO_DEVICE); return tlb_addr; diff --git a/kernel/events/core.c b/kernel/events/core.c index 58ecb1c243..7c03305797 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -450,8 +450,8 @@ static void update_perf_cpu_limits(void) static bool perf_rotate_context(struct perf_cpu_pmu_context *cpc); -int perf_proc_update_handler(struct ctl_table *table, int write, - void *buffer, size_t *lenp, loff_t *ppos) +int perf_event_max_sample_rate_handler(struct ctl_table *table, int write, + void *buffer, size_t *lenp, loff_t *ppos) { int ret; int perf_cpu = sysctl_perf_cpu_time_max_percent; @@ -4457,6 +4457,9 @@ static int __perf_event_read_cpu(struct perf_event *event, int event_cpu) { u16 local_pkg, event_pkg; + if ((unsigned)event_cpu >= nr_cpu_ids) + return event_cpu; + if (event->group_caps & PERF_EV_CAP_READ_ACTIVE_PKG) { int local_cpu = smp_processor_id(); @@ -4559,6 +4562,8 @@ int perf_event_read_local(struct perf_event *event, u64 *value, u64 *enabled, u64 *running) { unsigned long flags; + int event_oncpu; + int event_cpu; int ret = 0; /* @@ -4583,15 +4588,22 @@ int perf_event_read_local(struct perf_event *event, u64 *value, goto out; } + /* + * Get the event CPU numbers, and adjust them to local if the event is + * a per-package event that can be read locally + */ + event_oncpu = __perf_event_read_cpu(event, event->oncpu); + event_cpu = __perf_event_read_cpu(event, event->cpu); + /* If this is a per-CPU event, it must be for this CPU */ if (!(event->attach_state & PERF_ATTACH_TASK) && - event->cpu != smp_processor_id()) { + event_cpu != smp_processor_id()) { ret = -EINVAL; goto out; } /* If this is a pinned event it must be running on this CPU */ - if (event->attr.pinned && event->oncpu != smp_processor_id()) { + if (event->attr.pinned && event_oncpu != smp_processor_id()) { ret = -EBUSY; goto out; } @@ -4601,7 +4613,7 @@ int perf_event_read_local(struct perf_event *event, u64 *value, * or local to this CPU. Furthermore it means its ACTIVE (otherwise * oncpu == -1). */ - if (event->oncpu == smp_processor_id()) + if (event_oncpu == smp_processor_id()) event->pmu->read(event); *value = local64_read(&event->count); @@ -11413,9 +11425,30 @@ static DEVICE_ATTR_RW(perf_event_mux_interval_ms); static struct attribute *pmu_dev_attrs[] = { &dev_attr_type.attr, &dev_attr_perf_event_mux_interval_ms.attr, + &dev_attr_nr_addr_filters.attr, + NULL, +}; + +static umode_t pmu_dev_is_visible(struct kobject *kobj, struct attribute *a, int n) +{ + struct device *dev = kobj_to_dev(kobj); + struct pmu *pmu = dev_get_drvdata(dev); + + if (n == 2 && !pmu->nr_addr_filters) + return 0; + + return a->mode; +} + +static struct attribute_group pmu_dev_attr_group = { + .is_visible = pmu_dev_is_visible, + .attrs = pmu_dev_attrs, +}; + +static const struct attribute_group *pmu_dev_groups[] = { + &pmu_dev_attr_group, NULL, }; -ATTRIBUTE_GROUPS(pmu_dev); static int pmu_bus_running; static struct bus_type pmu_bus = { @@ -11452,18 +11485,11 @@ static int pmu_dev_alloc(struct pmu *pmu) if (ret) goto free_dev; - /* For PMUs with address filters, throw in an extra attribute: */ - if (pmu->nr_addr_filters) - ret = device_create_file(pmu->dev, &dev_attr_nr_addr_filters); - - if (ret) - goto del_dev; - - if (pmu->attr_update) + if (pmu->attr_update) { ret = sysfs_update_groups(&pmu->dev->kobj, pmu->attr_update); - - if (ret) - goto del_dev; + if (ret) + goto del_dev; + } out: return ret; diff --git a/kernel/events/uprobes.c b/kernel/events/uprobes.c index 3048589e2e..435aac1d8c 100644 --- a/kernel/events/uprobes.c +++ b/kernel/events/uprobes.c @@ -474,8 +474,8 @@ retry: gup_flags |= FOLL_SPLIT_PMD; /* Read the page with vaddr into memory */ old_page = get_user_page_vma_remote(mm, vaddr, gup_flags, &vma); - if (IS_ERR_OR_NULL(old_page)) - return old_page ? PTR_ERR(old_page) : 0; + if (IS_ERR(old_page)) + return PTR_ERR(old_page); ret = verify_opcode(old_page, vaddr, &opcode); if (ret <= 0) diff --git a/kernel/exit.c b/kernel/exit.c index 21a59a6e1f..aedc0832c9 100644 --- a/kernel/exit.c +++ b/kernel/exit.c @@ -74,6 +74,8 @@ #include <asm/unistd.h> #include <asm/mmu_context.h> +#include "exit.h" + /* * The default value should be high enough to not crash a system that randomly * crashes its kernel from time to time, but low enough to at least not permit @@ -133,7 +135,6 @@ static void __unhash_process(struct task_struct *p, bool group_dead) list_del_init(&p->sibling); __this_cpu_dec(process_counts); } - list_del_rcu(&p->thread_group); list_del_rcu(&p->thread_node); } @@ -539,7 +540,6 @@ static void exit_mm(void) exit_mm_release(current, mm); if (!mm) return; - sync_mm_rss(mm); mmap_read_lock(mm); mmgrab_lazy_tlb(mm); BUG_ON(mm != current->active_mm); @@ -827,9 +827,6 @@ void __noreturn do_exit(long code) io_uring_files_cancel(); exit_signals(tsk); /* sets PF_EXITING */ - /* sync mm's RSS info before statistics gathering */ - if (tsk->mm) - sync_mm_rss(tsk->mm); acct_update_integrals(tsk); group_dead = atomic_dec_and_test(&tsk->signal->live); if (group_dead) { @@ -1034,26 +1031,6 @@ SYSCALL_DEFINE1(exit_group, int, error_code) return 0; } -struct waitid_info { - pid_t pid; - uid_t uid; - int status; - int cause; -}; - -struct wait_opts { - enum pid_type wo_type; - int wo_flags; - struct pid *wo_pid; - - struct waitid_info *wo_info; - int wo_stat; - struct rusage *wo_rusage; - - wait_queue_entry_t child_wait; - int notask_error; -}; - static int eligible_pid(struct wait_opts *wo, struct task_struct *p) { return wo->wo_type == PIDTYPE_MAX || @@ -1517,6 +1494,17 @@ static int ptrace_do_wait(struct wait_opts *wo, struct task_struct *tsk) return 0; } +bool pid_child_should_wake(struct wait_opts *wo, struct task_struct *p) +{ + if (!eligible_pid(wo, p)) + return false; + + if ((wo->wo_flags & __WNOTHREAD) && wo->child_wait.private != p->parent) + return false; + + return true; +} + static int child_wait_callback(wait_queue_entry_t *wait, unsigned mode, int sync, void *key) { @@ -1524,13 +1512,10 @@ static int child_wait_callback(wait_queue_entry_t *wait, unsigned mode, child_wait); struct task_struct *p = key; - if (!eligible_pid(wo, p)) - return 0; + if (pid_child_should_wake(wo, p)) + return default_wake_function(wait, mode, sync, key); - if ((wo->wo_flags & __WNOTHREAD) && wait->private != p->parent) - return 0; - - return default_wake_function(wait, mode, sync, key); + return 0; } void __wake_up_parent(struct task_struct *p, struct task_struct *parent) @@ -1579,16 +1564,10 @@ static int do_wait_pid(struct wait_opts *wo) return 0; } -static long do_wait(struct wait_opts *wo) +long __do_wait(struct wait_opts *wo) { - int retval; + long retval; - trace_sched_process_wait(wo->wo_pid); - - init_waitqueue_func_entry(&wo->child_wait, child_wait_callback); - wo->child_wait.private = current; - add_wait_queue(¤t->signal->wait_chldexit, &wo->child_wait); -repeat: /* * If there is nothing that can match our criteria, just get out. * We will clear ->notask_error to zero if we see any child that @@ -1600,24 +1579,23 @@ repeat: (!wo->wo_pid || !pid_has_task(wo->wo_pid, wo->wo_type))) goto notask; - set_current_state(TASK_INTERRUPTIBLE); read_lock(&tasklist_lock); if (wo->wo_type == PIDTYPE_PID) { retval = do_wait_pid(wo); if (retval) - goto end; + return retval; } else { struct task_struct *tsk = current; do { retval = do_wait_thread(wo, tsk); if (retval) - goto end; + return retval; retval = ptrace_do_wait(wo, tsk); if (retval) - goto end; + return retval; if (wo->wo_flags & __WNOTHREAD) break; @@ -1627,27 +1605,44 @@ repeat: notask: retval = wo->notask_error; - if (!retval && !(wo->wo_flags & WNOHANG)) { - retval = -ERESTARTSYS; - if (!signal_pending(current)) { - schedule(); - goto repeat; - } - } -end: + if (!retval && !(wo->wo_flags & WNOHANG)) + return -ERESTARTSYS; + + return retval; +} + +static long do_wait(struct wait_opts *wo) +{ + int retval; + + trace_sched_process_wait(wo->wo_pid); + + init_waitqueue_func_entry(&wo->child_wait, child_wait_callback); + wo->child_wait.private = current; + add_wait_queue(¤t->signal->wait_chldexit, &wo->child_wait); + + do { + set_current_state(TASK_INTERRUPTIBLE); + retval = __do_wait(wo); + if (retval != -ERESTARTSYS) + break; + if (signal_pending(current)) + break; + schedule(); + } while (1); + __set_current_state(TASK_RUNNING); remove_wait_queue(¤t->signal->wait_chldexit, &wo->child_wait); return retval; } -static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, - int options, struct rusage *ru) +int kernel_waitid_prepare(struct wait_opts *wo, int which, pid_t upid, + struct waitid_info *infop, int options, + struct rusage *ru) { - struct wait_opts wo; + unsigned int f_flags = 0; struct pid *pid = NULL; enum pid_type type; - long ret; - unsigned int f_flags = 0; if (options & ~(WNOHANG|WNOWAIT|WEXITED|WSTOPPED|WCONTINUED| __WNOTHREAD|__WCLONE|__WALL)) @@ -1690,19 +1685,32 @@ static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, return -EINVAL; } - wo.wo_type = type; - wo.wo_pid = pid; - wo.wo_flags = options; - wo.wo_info = infop; - wo.wo_rusage = ru; + wo->wo_type = type; + wo->wo_pid = pid; + wo->wo_flags = options; + wo->wo_info = infop; + wo->wo_rusage = ru; if (f_flags & O_NONBLOCK) - wo.wo_flags |= WNOHANG; + wo->wo_flags |= WNOHANG; + + return 0; +} + +static long kernel_waitid(int which, pid_t upid, struct waitid_info *infop, + int options, struct rusage *ru) +{ + struct wait_opts wo; + long ret; + + ret = kernel_waitid_prepare(&wo, which, upid, infop, options, ru); + if (ret) + return ret; ret = do_wait(&wo); - if (!ret && !(options & WNOHANG) && (f_flags & O_NONBLOCK)) + if (!ret && !(options & WNOHANG) && (wo.wo_flags & WNOHANG)) ret = -EAGAIN; - put_pid(pid); + put_pid(wo.wo_pid); return ret; } diff --git a/kernel/exit.h b/kernel/exit.h new file mode 100644 index 0000000000..278faa26a6 --- /dev/null +++ b/kernel/exit.h @@ -0,0 +1,30 @@ +// SPDX-License-Identifier: GPL-2.0-only +#ifndef LINUX_WAITID_H +#define LINUX_WAITID_H + +struct waitid_info { + pid_t pid; + uid_t uid; + int status; + int cause; +}; + +struct wait_opts { + enum pid_type wo_type; + int wo_flags; + struct pid *wo_pid; + + struct waitid_info *wo_info; + int wo_stat; + struct rusage *wo_rusage; + + wait_queue_entry_t child_wait; + int notask_error; +}; + +bool pid_child_should_wake(struct wait_opts *wo, struct task_struct *p); +long __do_wait(struct wait_opts *wo); +int kernel_waitid_prepare(struct wait_opts *wo, int which, pid_t upid, + struct waitid_info *infop, int options, + struct rusage *ru); +#endif diff --git a/kernel/fork.c b/kernel/fork.c index 177ce7438d..10917c3e1f 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -733,7 +733,7 @@ static __latent_entropy int dup_mmap(struct mm_struct *mm, get_file(file); i_mmap_lock_write(mapping); - if (tmp->vm_flags & VM_SHARED) + if (vma_is_shared_maywrite(tmp)) mapping_allow_writable(mapping); flush_dcache_mmap_lock(mapping); /* insert tmp into the share list, just after mpnt */ @@ -1393,6 +1393,8 @@ EXPORT_SYMBOL_GPL(mmput_async); /** * set_mm_exe_file - change a reference to the mm's executable file + * @mm: The mm to change. + * @new_exe_file: The new file to use. * * This changes mm's executable file (shown as symlink /proc/[pid]/exe). * @@ -1432,6 +1434,8 @@ int set_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) /** * replace_mm_exe_file - replace a reference to the mm's executable file + * @mm: The mm to change. + * @new_exe_file: The new file to use. * * This changes mm's executable file (shown as symlink /proc/[pid]/exe). * @@ -1483,6 +1487,7 @@ int replace_mm_exe_file(struct mm_struct *mm, struct file *new_exe_file) /** * get_mm_exe_file - acquire a reference to the mm's executable file + * @mm: The mm of interest. * * Returns %NULL if mm has no associated executable file. * User must release file via fput(). @@ -1492,15 +1497,14 @@ struct file *get_mm_exe_file(struct mm_struct *mm) struct file *exe_file; rcu_read_lock(); - exe_file = rcu_dereference(mm->exe_file); - if (exe_file && !get_file_rcu(exe_file)) - exe_file = NULL; + exe_file = get_file_rcu(&mm->exe_file); rcu_read_unlock(); return exe_file; } /** * get_task_exe_file - acquire a reference to the task's executable file + * @task: The task. * * Returns %NULL if task's mm (if any) has no associated executable file or * this is a kernel thread with borrowed mm (see the comment above get_task_mm). @@ -1523,6 +1527,7 @@ struct file *get_task_exe_file(struct task_struct *task) /** * get_task_mm - acquire a reference to the task's mm + * @task: The task. * * Returns %NULL if the task has no mm. Checks PF_KTHREAD (meaning * this kernel workthread has transiently adopted a user mm with use_mm, @@ -2102,11 +2107,11 @@ const struct file_operations pidfd_fops = { * __pidfd_prepare - allocate a new pidfd_file and reserve a pidfd * @pid: the struct pid for which to create a pidfd * @flags: flags of the new @pidfd - * @pidfd: the pidfd to return + * @ret: Where to return the file for the pidfd. * * Allocate a new file that stashes @pid and reserve a new pidfd number in the * caller's file descriptor table. The pidfd is reserved but not installed yet. - + * * The helper doesn't perform checks on @pid which makes it useful for pidfds * created via CLONE_PIDFD where @pid has no task attached when the pidfd and * pidfd file are prepared. @@ -2153,7 +2158,7 @@ static int __pidfd_prepare(struct pid *pid, unsigned int flags, struct file **re * pidfd_prepare - allocate a new pidfd_file and reserve a pidfd * @pid: the struct pid for which to create a pidfd * @flags: flags of the new @pidfd - * @pidfd: the pidfd to return + * @ret: Where to return the pidfd. * * Allocate a new file that stashes @pid and reserve a new pidfd number in the * caller's file descriptor table. The pidfd is reserved but not installed yet. @@ -2406,10 +2411,6 @@ __latent_entropy struct task_struct *copy_process( p->io_uring = NULL; #endif -#if defined(SPLIT_RSS_COUNTING) - memset(&p->rss_stat, 0, sizeof(p->rss_stat)); -#endif - p->default_timer_slack_ns = current->timer_slack_ns; #ifdef CONFIG_PSI @@ -2576,7 +2577,6 @@ __latent_entropy struct task_struct *copy_process( p->dirty_paused_when = 0; p->pdeath_signal = 0; - INIT_LIST_HEAD(&p->thread_group); p->task_works = NULL; clear_posix_cputimers_work(p); @@ -2704,8 +2704,6 @@ __latent_entropy struct task_struct *copy_process( atomic_inc(¤t->signal->live); refcount_inc(¤t->signal->sigcnt); task_join_group_stop(p); - list_add_tail_rcu(&p->thread_group, - &p->group_leader->thread_group); list_add_tail_rcu(&p->thread_node, &p->signal->thread_head); } @@ -3144,7 +3142,7 @@ static inline bool clone3_stack_valid(struct kernel_clone_args *kargs) if (!access_ok((void __user *)kargs->stack, kargs->stack_size)) return false; -#if !defined(CONFIG_STACK_GROWSUP) && !defined(CONFIG_IA64) +#if !defined(CONFIG_STACK_GROWSUP) kargs->stack += kargs->stack_size; #endif } @@ -3181,7 +3179,7 @@ static bool clone3_args_valid(struct kernel_clone_args *kargs) } /** - * clone3 - create a new process with specific properties + * sys_clone3 - create a new process with specific properties * @uargs: argument structure * @size: size of @uargs * diff --git a/kernel/freezer.c b/kernel/freezer.c index 4fad0e6fca..759006a9a9 100644 --- a/kernel/freezer.c +++ b/kernel/freezer.c @@ -71,7 +71,11 @@ bool __refrigerator(bool check_kthr_stop) for (;;) { bool freeze; + raw_spin_lock_irq(¤t->pi_lock); set_current_state(TASK_FROZEN); + /* unstale saved_state so that __thaw_task() will wake us up */ + current->saved_state = TASK_RUNNING; + raw_spin_unlock_irq(¤t->pi_lock); spin_lock_irq(&freezer_lock); freeze = freezing(current) && !(check_kthr_stop && kthread_should_stop()); @@ -129,6 +133,7 @@ static int __set_task_frozen(struct task_struct *p, void *arg) WARN_ON_ONCE(debug_locks && p->lockdep_depth); #endif + p->saved_state = p->__state; WRITE_ONCE(p->__state, TASK_FROZEN); return TASK_FROZEN; } @@ -170,42 +175,34 @@ bool freeze_task(struct task_struct *p) } /* - * The special task states (TASK_STOPPED, TASK_TRACED) keep their canonical - * state in p->jobctl. If either of them got a wakeup that was missed because - * TASK_FROZEN, then their canonical state reflects that and the below will - * refuse to restore the special state and instead issue the wakeup. + * Restore the saved_state before the task entered freezer. For typical task + * in the __refrigerator(), saved_state == TASK_RUNNING so nothing happens + * here. For tasks which were TASK_NORMAL | TASK_FREEZABLE, their initial state + * is restored unless they got an expected wakeup (see ttwu_state_match()). + * Returns 1 if the task state was restored. */ -static int __set_task_special(struct task_struct *p, void *arg) +static int __restore_freezer_state(struct task_struct *p, void *arg) { - unsigned int state = 0; + unsigned int state = p->saved_state; - if (p->jobctl & JOBCTL_TRACED) - state = TASK_TRACED; - - else if (p->jobctl & JOBCTL_STOPPED) - state = TASK_STOPPED; - - if (state) + if (state != TASK_RUNNING) { WRITE_ONCE(p->__state, state); + return 1; + } - return state; + return 0; } void __thaw_task(struct task_struct *p) { - unsigned long flags, flags2; + unsigned long flags; spin_lock_irqsave(&freezer_lock, flags); if (WARN_ON_ONCE(freezing(p))) goto unlock; - if (lock_task_sighand(p, &flags2)) { - /* TASK_FROZEN -> TASK_{STOPPED,TRACED} */ - bool ret = task_call_func(p, __set_task_special, NULL); - unlock_task_sighand(p, &flags2); - if (ret) - goto unlock; - } + if (!frozen(p) || task_call_func(p, __restore_freezer_state, NULL)) + goto unlock; wake_up_state(p, TASK_FROZEN); unlock: diff --git a/kernel/futex/core.c b/kernel/futex/core.c index f30a93e50f..52d0bf67e7 100644 --- a/kernel/futex/core.c +++ b/kernel/futex/core.c @@ -193,7 +193,7 @@ static u64 get_inode_sequence_number(struct inode *inode) /** * get_futex_key() - Get parameters which are the keys for a futex * @uaddr: virtual address of the futex - * @fshared: false for a PROCESS_PRIVATE futex, true for PROCESS_SHARED + * @flags: FLAGS_* * @key: address where result is stored. * @rw: mapping needs to be read/write (values: FUTEX_READ, * FUTEX_WRITE) @@ -217,14 +217,18 @@ static u64 get_inode_sequence_number(struct inode *inode) * * lock_page() might sleep, the caller should not hold a spinlock. */ -int get_futex_key(u32 __user *uaddr, bool fshared, union futex_key *key, +int get_futex_key(u32 __user *uaddr, unsigned int flags, union futex_key *key, enum futex_access rw) { unsigned long address = (unsigned long)uaddr; struct mm_struct *mm = current->mm; - struct page *page, *tail; + struct page *page; + struct folio *folio; struct address_space *mapping; int err, ro = 0; + bool fshared; + + fshared = flags & FLAGS_SHARED; /* * The futex address must be "naturally" aligned. @@ -283,54 +287,52 @@ again: err = 0; /* - * The treatment of mapping from this point on is critical. The page - * lock protects many things but in this context the page lock + * The treatment of mapping from this point on is critical. The folio + * lock protects many things but in this context the folio lock * stabilizes mapping, prevents inode freeing in the shared * file-backed region case and guards against movement to swap cache. * - * Strictly speaking the page lock is not needed in all cases being - * considered here and page lock forces unnecessarily serialization + * Strictly speaking the folio lock is not needed in all cases being + * considered here and folio lock forces unnecessarily serialization. * From this point on, mapping will be re-verified if necessary and - * page lock will be acquired only if it is unavoidable + * folio lock will be acquired only if it is unavoidable * - * Mapping checks require the head page for any compound page so the - * head page and mapping is looked up now. For anonymous pages, it - * does not matter if the page splits in the future as the key is - * based on the address. For filesystem-backed pages, the tail is - * required as the index of the page determines the key. For - * base pages, there is no tail page and tail == page. + * Mapping checks require the folio so it is looked up now. For + * anonymous pages, it does not matter if the folio is split + * in the future as the key is based on the address. For + * filesystem-backed pages, the precise page is required as the + * index of the page determines the key. */ - tail = page; - page = compound_head(page); - mapping = READ_ONCE(page->mapping); + folio = page_folio(page); + mapping = READ_ONCE(folio->mapping); /* - * If page->mapping is NULL, then it cannot be a PageAnon + * If folio->mapping is NULL, then it cannot be an anonymous * page; but it might be the ZERO_PAGE or in the gate area or * in a special mapping (all cases which we are happy to fail); * or it may have been a good file page when get_user_pages_fast * found it, but truncated or holepunched or subjected to - * invalidate_complete_page2 before we got the page lock (also + * invalidate_complete_page2 before we got the folio lock (also * cases which we are happy to fail). And we hold a reference, * so refcount care in invalidate_inode_page's remove_mapping * prevents drop_caches from setting mapping to NULL beneath us. * * The case we do have to guard against is when memory pressure made * shmem_writepage move it from filecache to swapcache beneath us: - * an unlikely race, but we do need to retry for page->mapping. + * an unlikely race, but we do need to retry for folio->mapping. */ if (unlikely(!mapping)) { int shmem_swizzled; /* - * Page lock is required to identify which special case above - * applies. If this is really a shmem page then the page lock + * Folio lock is required to identify which special case above + * applies. If this is really a shmem page then the folio lock * will prevent unexpected transitions. */ - lock_page(page); - shmem_swizzled = PageSwapCache(page) || page->mapping; - unlock_page(page); - put_page(page); + folio_lock(folio); + shmem_swizzled = folio_test_swapcache(folio) || folio->mapping; + folio_unlock(folio); + folio_put(folio); if (shmem_swizzled) goto again; @@ -341,14 +343,14 @@ again: /* * Private mappings are handled in a simple way. * - * If the futex key is stored on an anonymous page, then the associated + * If the futex key is stored in anonymous memory, then the associated * object is the mm which is implicitly pinned by the calling process. * * NOTE: When userspace waits on a MAP_SHARED mapping, even if * it's a read-only handle, it's expected that futexes attach to * the object not the particular process. */ - if (PageAnon(page)) { + if (folio_test_anon(folio)) { /* * A RO anonymous page will never change and thus doesn't make * sense for futex operations. @@ -367,10 +369,10 @@ again: /* * The associated futex object in this case is the inode and - * the page->mapping must be traversed. Ordinarily this should - * be stabilised under page lock but it's not strictly + * the folio->mapping must be traversed. Ordinarily this should + * be stabilised under folio lock but it's not strictly * necessary in this case as we just want to pin the inode, not - * update the radix tree or anything like that. + * update i_pages or anything like that. * * The RCU read lock is taken as the inode is finally freed * under RCU. If the mapping still matches expectations then the @@ -378,9 +380,9 @@ again: */ rcu_read_lock(); - if (READ_ONCE(page->mapping) != mapping) { + if (READ_ONCE(folio->mapping) != mapping) { rcu_read_unlock(); - put_page(page); + folio_put(folio); goto again; } @@ -388,19 +390,19 @@ again: inode = READ_ONCE(mapping->host); if (!inode) { rcu_read_unlock(); - put_page(page); + folio_put(folio); goto again; } key->both.offset |= FUT_OFF_INODE; /* inode-based key */ key->shared.i_seq = get_inode_sequence_number(inode); - key->shared.pgoff = page_to_pgoff(tail); + key->shared.pgoff = folio->index + folio_page_idx(folio, page); rcu_read_unlock(); } out: - put_page(page); + folio_put(folio); return err; } @@ -624,12 +626,21 @@ retry: } /* - * PI futexes can not be requeued and must remove themselves from the - * hash bucket. The hash bucket lock (i.e. lock_ptr) is held. + * PI futexes can not be requeued and must remove themselves from the hash + * bucket. The hash bucket lock (i.e. lock_ptr) is held. */ void futex_unqueue_pi(struct futex_q *q) { - __futex_unqueue(q); + /* + * If the lock was not acquired (due to timeout or signal) then the + * rt_waiter is removed before futex_q is. If this is observed by + * an unlocker after dropping the rtmutex wait lock and before + * acquiring the hash bucket lock, then the unlocker dequeues the + * futex_q from the hash bucket list to guarantee consistent state + * vs. userspace. Therefore the dequeue here must be conditional. + */ + if (!plist_node_empty(&q->list)) + __futex_unqueue(q); BUG_ON(!q->pi_state); put_pi_state(q->pi_state); @@ -698,7 +709,8 @@ retry: owner = uval & FUTEX_TID_MASK; if (pending_op && !pi && !owner) { - futex_wake(uaddr, 1, 1, FUTEX_BITSET_MATCH_ANY); + futex_wake(uaddr, FLAGS_SIZE_32 | FLAGS_SHARED, 1, + FUTEX_BITSET_MATCH_ANY); return 0; } @@ -750,8 +762,10 @@ retry: * Wake robust non-PI futexes here. The wakeup of * PI futexes happens in exit_pi_state(): */ - if (!pi && (uval & FUTEX_WAITERS)) - futex_wake(uaddr, 1, 1, FUTEX_BITSET_MATCH_ANY); + if (!pi && (uval & FUTEX_WAITERS)) { + futex_wake(uaddr, FLAGS_SIZE_32 | FLAGS_SHARED, 1, + FUTEX_BITSET_MATCH_ANY); + } return 0; } diff --git a/kernel/futex/futex.h b/kernel/futex/futex.h index b5379c0e6d..8b195d06f4 100644 --- a/kernel/futex/futex.h +++ b/kernel/futex/futex.h @@ -5,6 +5,7 @@ #include <linux/futex.h> #include <linux/rtmutex.h> #include <linux/sched/wake_q.h> +#include <linux/compat.h> #ifdef CONFIG_PREEMPT_RT #include <linux/rcuwait.h> @@ -16,17 +17,86 @@ * Futex flags used to encode options to functions and preserve them across * restarts. */ +#define FLAGS_SIZE_8 0x0000 +#define FLAGS_SIZE_16 0x0001 +#define FLAGS_SIZE_32 0x0002 +#define FLAGS_SIZE_64 0x0003 + +#define FLAGS_SIZE_MASK 0x0003 + #ifdef CONFIG_MMU -# define FLAGS_SHARED 0x01 +# define FLAGS_SHARED 0x0010 #else /* * NOMMU does not have per process address space. Let the compiler optimize * code away. */ -# define FLAGS_SHARED 0x00 +# define FLAGS_SHARED 0x0000 #endif -#define FLAGS_CLOCKRT 0x02 -#define FLAGS_HAS_TIMEOUT 0x04 +#define FLAGS_CLOCKRT 0x0020 +#define FLAGS_HAS_TIMEOUT 0x0040 +#define FLAGS_NUMA 0x0080 +#define FLAGS_STRICT 0x0100 + +/* FUTEX_ to FLAGS_ */ +static inline unsigned int futex_to_flags(unsigned int op) +{ + unsigned int flags = FLAGS_SIZE_32; + + if (!(op & FUTEX_PRIVATE_FLAG)) + flags |= FLAGS_SHARED; + + if (op & FUTEX_CLOCK_REALTIME) + flags |= FLAGS_CLOCKRT; + + return flags; +} + +#define FUTEX2_VALID_MASK (FUTEX2_SIZE_MASK | FUTEX2_PRIVATE) + +/* FUTEX2_ to FLAGS_ */ +static inline unsigned int futex2_to_flags(unsigned int flags2) +{ + unsigned int flags = flags2 & FUTEX2_SIZE_MASK; + + if (!(flags2 & FUTEX2_PRIVATE)) + flags |= FLAGS_SHARED; + + if (flags2 & FUTEX2_NUMA) + flags |= FLAGS_NUMA; + + return flags; +} + +static inline unsigned int futex_size(unsigned int flags) +{ + return 1 << (flags & FLAGS_SIZE_MASK); +} + +static inline bool futex_flags_valid(unsigned int flags) +{ + /* Only 64bit futexes for 64bit code */ + if (!IS_ENABLED(CONFIG_64BIT) || in_compat_syscall()) { + if ((flags & FLAGS_SIZE_MASK) == FLAGS_SIZE_64) + return false; + } + + /* Only 32bit futexes are implemented -- for now */ + if ((flags & FLAGS_SIZE_MASK) != FLAGS_SIZE_32) + return false; + + return true; +} + +static inline bool futex_validate_input(unsigned int flags, u64 val) +{ + int bits = 8 * futex_size(flags); + + if (bits < 64 && (val >> bits)) + return false; + + return true; +} #ifdef CONFIG_FAIL_FUTEX extern bool should_fail_futex(bool fshared); @@ -69,11 +139,16 @@ struct futex_pi_state { union futex_key key; } __randomize_layout; +struct futex_q; +typedef void (futex_wake_fn)(struct wake_q_head *wake_q, struct futex_q *q); + /** * struct futex_q - The hashed futex queue entry, one per waiting task * @list: priority-sorted list of tasks waiting on this futex * @task: the task waiting on the futex * @lock_ptr: the hash bucket lock + * @wake: the wake handler for this queue + * @wake_data: data associated with the wake handler * @key: the key the futex is hashed on * @pi_state: optional priority inheritance state * @rt_waiter: rt_waiter storage for use with requeue_pi @@ -98,6 +173,8 @@ struct futex_q { struct task_struct *task; spinlock_t *lock_ptr; + futex_wake_fn *wake; + void *wake_data; union futex_key key; struct futex_pi_state *pi_state; struct rt_mutex_waiter *rt_waiter; @@ -116,7 +193,7 @@ enum futex_access { FUTEX_WRITE }; -extern int get_futex_key(u32 __user *uaddr, bool fshared, union futex_key *key, +extern int get_futex_key(u32 __user *uaddr, unsigned int flags, union futex_key *key, enum futex_access rw); extern struct hrtimer_sleeper * @@ -144,6 +221,7 @@ extern int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags, struct futex_q *q, struct futex_hash_bucket **hb); extern void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, struct hrtimer_sleeper *timeout); +extern bool __futex_wake_mark(struct futex_q *q); extern void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q); extern int fault_in_user_writeable(u32 __user *uaddr); @@ -260,10 +338,14 @@ extern int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset, u32 __user *uaddr2); -extern int futex_requeue(u32 __user *uaddr1, unsigned int flags, - u32 __user *uaddr2, int nr_wake, int nr_requeue, +extern int futex_requeue(u32 __user *uaddr1, unsigned int flags1, + u32 __user *uaddr2, unsigned int flags2, + int nr_wake, int nr_requeue, u32 *cmpval, int requeue_pi); +extern int __futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, + struct hrtimer_sleeper *to, u32 bitset); + extern int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset); @@ -279,6 +361,16 @@ struct futex_vector { struct futex_q q; }; +extern int futex_parse_waitv(struct futex_vector *futexv, + struct futex_waitv __user *uwaitv, + unsigned int nr_futexes, futex_wake_fn *wake, + void *wake_data); + +extern int futex_wait_multiple_setup(struct futex_vector *vs, int count, + int *woken); + +extern int futex_unqueue_multiple(struct futex_vector *v, int count); + extern int futex_wait_multiple(struct futex_vector *vs, unsigned int count, struct hrtimer_sleeper *to); diff --git a/kernel/futex/pi.c b/kernel/futex/pi.c index ce2889f123..5722467f27 100644 --- a/kernel/futex/pi.c +++ b/kernel/futex/pi.c @@ -1,6 +1,7 @@ // SPDX-License-Identifier: GPL-2.0-or-later #include <linux/slab.h> +#include <linux/sched/rt.h> #include <linux/sched/task.h> #include "futex.h" @@ -610,29 +611,16 @@ int futex_lock_pi_atomic(u32 __user *uaddr, struct futex_hash_bucket *hb, /* * Caller must hold a reference on @pi_state. */ -static int wake_futex_pi(u32 __user *uaddr, u32 uval, struct futex_pi_state *pi_state) +static int wake_futex_pi(u32 __user *uaddr, u32 uval, + struct futex_pi_state *pi_state, + struct rt_mutex_waiter *top_waiter) { - struct rt_mutex_waiter *top_waiter; struct task_struct *new_owner; bool postunlock = false; DEFINE_RT_WAKE_Q(wqh); u32 curval, newval; int ret = 0; - top_waiter = rt_mutex_top_waiter(&pi_state->pi_mutex); - if (WARN_ON_ONCE(!top_waiter)) { - /* - * As per the comment in futex_unlock_pi() this should not happen. - * - * When this happens, give up our locks and try again, giving - * the futex_lock_pi() instance time to complete, either by - * waiting on the rtmutex or removing itself from the futex - * queue. - */ - ret = -EAGAIN; - goto out_unlock; - } - new_owner = top_waiter->task; /* @@ -945,7 +933,7 @@ int futex_lock_pi(u32 __user *uaddr, unsigned int flags, ktime_t *time, int tryl to = futex_setup_timer(time, &timeout, flags, 0); retry: - ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q.key, FUTEX_WRITE); + ret = get_futex_key(uaddr, flags, &q.key, FUTEX_WRITE); if (unlikely(ret != 0)) goto out; @@ -1002,6 +990,12 @@ retry_private: goto no_block; } + /* + * Must be done before we enqueue the waiter, here is unfortunately + * under the hb lock, but that *should* work because it does nothing. + */ + rt_mutex_pre_schedule(); + rt_mutex_init_waiter(&rt_waiter); /* @@ -1039,19 +1033,37 @@ retry_private: ret = rt_mutex_wait_proxy_lock(&q.pi_state->pi_mutex, to, &rt_waiter); cleanup: - spin_lock(q.lock_ptr); /* * If we failed to acquire the lock (deadlock/signal/timeout), we must - * first acquire the hb->lock before removing the lock from the - * rt_mutex waitqueue, such that we can keep the hb and rt_mutex wait - * lists consistent. + * must unwind the above, however we canont lock hb->lock because + * rt_mutex already has a waiter enqueued and hb->lock can itself try + * and enqueue an rt_waiter through rtlock. + * + * Doing the cleanup without holding hb->lock can cause inconsistent + * state between hb and pi_state, but only in the direction of not + * seeing a waiter that is leaving. + * + * See futex_unlock_pi(), it deals with this inconsistency. + * + * There be dragons here, since we must deal with the inconsistency on + * the way out (here), it is impossible to detect/warn about the race + * the other way around (missing an incoming waiter). * - * In particular; it is important that futex_unlock_pi() can not - * observe this inconsistency. + * What could possibly go wrong... */ if (ret && !rt_mutex_cleanup_proxy_lock(&q.pi_state->pi_mutex, &rt_waiter)) ret = 0; + /* + * Now that the rt_waiter has been dequeued, it is safe to use + * spinlock/rtlock (which might enqueue its own rt_waiter) and fix up + * the + */ + spin_lock(q.lock_ptr); + /* + * Waiter is unqueued. + */ + rt_mutex_post_schedule(); no_block: /* * Fixup the pi_state owner and possibly acquire the lock if we @@ -1117,12 +1129,13 @@ retry: if ((uval & FUTEX_TID_MASK) != vpid) return -EPERM; - ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_WRITE); + ret = get_futex_key(uaddr, flags, &key, FUTEX_WRITE); if (ret) return ret; hb = futex_hash(&key); spin_lock(&hb->lock); +retry_hb: /* * Check waiters first. We do not trust user space values at @@ -1132,6 +1145,7 @@ retry: top_waiter = futex_top_waiter(hb, &key); if (top_waiter) { struct futex_pi_state *pi_state = top_waiter->pi_state; + struct rt_mutex_waiter *rt_waiter; ret = -EINVAL; if (!pi_state) @@ -1144,22 +1158,44 @@ retry: if (pi_state->owner != current) goto out_unlock; - get_pi_state(pi_state); /* * By taking wait_lock while still holding hb->lock, we ensure - * there is no point where we hold neither; and therefore - * wake_futex_p() must observe a state consistent with what we - * observed. + * there is no point where we hold neither; and thereby + * wake_futex_pi() must observe any new waiters. + * + * Since the cleanup: case in futex_lock_pi() removes the + * rt_waiter without holding hb->lock, it is possible for + * wake_futex_pi() to not find a waiter while the above does, + * in this case the waiter is on the way out and it can be + * ignored. * * In particular; this forces __rt_mutex_start_proxy() to * complete such that we're guaranteed to observe the - * rt_waiter. Also see the WARN in wake_futex_pi(). + * rt_waiter. */ raw_spin_lock_irq(&pi_state->pi_mutex.wait_lock); + + /* + * Futex vs rt_mutex waiter state -- if there are no rt_mutex + * waiters even though futex thinks there are, then the waiter + * is leaving. The entry needs to be removed from the list so a + * new futex_lock_pi() is not using this stale PI-state while + * the futex is available in user space again. + * There can be more than one task on its way out so it needs + * to retry. + */ + rt_waiter = rt_mutex_top_waiter(&pi_state->pi_mutex); + if (!rt_waiter) { + __futex_unqueue(top_waiter); + raw_spin_unlock_irq(&pi_state->pi_mutex.wait_lock); + goto retry_hb; + } + + get_pi_state(pi_state); spin_unlock(&hb->lock); /* drops pi_state->pi_mutex.wait_lock */ - ret = wake_futex_pi(uaddr, uval, pi_state); + ret = wake_futex_pi(uaddr, uval, pi_state, rt_waiter); put_pi_state(pi_state); diff --git a/kernel/futex/requeue.c b/kernel/futex/requeue.c index cba8b1a6a4..eb21f06581 100644 --- a/kernel/futex/requeue.c +++ b/kernel/futex/requeue.c @@ -58,6 +58,7 @@ enum { const struct futex_q futex_q_init = { /* list gets initialized in futex_queue()*/ + .wake = futex_wake_mark, .key = FUTEX_KEY_INIT, .bitset = FUTEX_BITSET_MATCH_ANY, .requeue_state = ATOMIC_INIT(Q_REQUEUE_PI_NONE), @@ -269,7 +270,7 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1, union futex_key *key2, struct futex_pi_state **ps, struct task_struct **exiting, int set_waiters) { - struct futex_q *top_waiter = NULL; + struct futex_q *top_waiter; u32 curval; int ret; @@ -346,8 +347,9 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1, /** * futex_requeue() - Requeue waiters from uaddr1 to uaddr2 * @uaddr1: source futex user address - * @flags: futex flags (FLAGS_SHARED, etc.) + * @flags1: futex flags (FLAGS_SHARED, etc.) * @uaddr2: target futex user address + * @flags2: futex flags (FLAGS_SHARED, etc.) * @nr_wake: number of waiters to wake (must be 1 for requeue_pi) * @nr_requeue: number of waiters to requeue (0-INT_MAX) * @cmpval: @uaddr1 expected value (or %NULL) @@ -361,7 +363,8 @@ futex_proxy_trylock_atomic(u32 __user *pifutex, struct futex_hash_bucket *hb1, * - >=0 - on success, the number of tasks requeued or woken; * - <0 - on error */ -int futex_requeue(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, +int futex_requeue(u32 __user *uaddr1, unsigned int flags1, + u32 __user *uaddr2, unsigned int flags2, int nr_wake, int nr_requeue, u32 *cmpval, int requeue_pi) { union futex_key key1 = FUTEX_KEY_INIT, key2 = FUTEX_KEY_INIT; @@ -424,10 +427,10 @@ int futex_requeue(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, } retry: - ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ); + ret = get_futex_key(uaddr1, flags1, &key1, FUTEX_READ); if (unlikely(ret != 0)) return ret; - ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, + ret = get_futex_key(uaddr2, flags2, &key2, requeue_pi ? FUTEX_WRITE : FUTEX_READ); if (unlikely(ret != 0)) return ret; @@ -459,7 +462,7 @@ retry_private: if (ret) return ret; - if (!(flags & FLAGS_SHARED)) + if (!(flags1 & FLAGS_SHARED)) goto retry_private; goto retry; @@ -591,7 +594,7 @@ retry_private: /* Plain futexes just wake or requeue and are done */ if (!requeue_pi) { if (++task_count <= nr_wake) - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); else requeue_futex(this, hb1, hb2, &key2); continue; @@ -789,7 +792,7 @@ int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, */ rt_mutex_init_waiter(&rt_waiter); - ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE); + ret = get_futex_key(uaddr2, flags, &key2, FUTEX_WRITE); if (unlikely(ret != 0)) goto out; @@ -850,11 +853,13 @@ int futex_wait_requeue_pi(u32 __user *uaddr, unsigned int flags, pi_mutex = &q.pi_state->pi_mutex; ret = rt_mutex_wait_proxy_lock(pi_mutex, to, &rt_waiter); - /* Current is not longer pi_blocked_on */ - spin_lock(q.lock_ptr); + /* + * See futex_unlock_pi()'s cleanup: comment. + */ if (ret && !rt_mutex_cleanup_proxy_lock(pi_mutex, &rt_waiter)) ret = 0; + spin_lock(q.lock_ptr); debug_rt_mutex_free_waiter(&rt_waiter); /* * Fixup the pi_state owner and possibly acquire the lock if we diff --git a/kernel/futex/syscalls.c b/kernel/futex/syscalls.c index a8074079b0..4b6da9116a 100644 --- a/kernel/futex/syscalls.c +++ b/kernel/futex/syscalls.c @@ -1,6 +1,5 @@ // SPDX-License-Identifier: GPL-2.0-or-later -#include <linux/compat.h> #include <linux/syscalls.h> #include <linux/time_namespace.h> @@ -85,15 +84,12 @@ err_unlock: long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, u32 __user *uaddr2, u32 val2, u32 val3) { + unsigned int flags = futex_to_flags(op); int cmd = op & FUTEX_CMD_MASK; - unsigned int flags = 0; - if (!(op & FUTEX_PRIVATE_FLAG)) - flags |= FLAGS_SHARED; - - if (op & FUTEX_CLOCK_REALTIME) { - flags |= FLAGS_CLOCKRT; - if (cmd != FUTEX_WAIT_BITSET && cmd != FUTEX_WAIT_REQUEUE_PI && + if (flags & FLAGS_CLOCKRT) { + if (cmd != FUTEX_WAIT_BITSET && + cmd != FUTEX_WAIT_REQUEUE_PI && cmd != FUTEX_LOCK_PI2) return -ENOSYS; } @@ -110,9 +106,9 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, case FUTEX_WAKE_BITSET: return futex_wake(uaddr, flags, val, val3); case FUTEX_REQUEUE: - return futex_requeue(uaddr, flags, uaddr2, val, val2, NULL, 0); + return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, NULL, 0); case FUTEX_CMP_REQUEUE: - return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 0); + return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, &val3, 0); case FUTEX_WAKE_OP: return futex_wake_op(uaddr, flags, uaddr2, val, val2, val3); case FUTEX_LOCK_PI: @@ -129,7 +125,7 @@ long do_futex(u32 __user *uaddr, int op, u32 val, ktime_t *timeout, return futex_wait_requeue_pi(uaddr, flags, val, timeout, val3, uaddr2); case FUTEX_CMP_REQUEUE_PI: - return futex_requeue(uaddr, flags, uaddr2, val, val2, &val3, 1); + return futex_requeue(uaddr, flags, uaddr2, flags, val, val2, &val3, 1); } return -ENOSYS; } @@ -183,43 +179,91 @@ SYSCALL_DEFINE6(futex, u32 __user *, uaddr, int, op, u32, val, return do_futex(uaddr, op, val, tp, uaddr2, (unsigned long)utime, val3); } -/* Mask of available flags for each futex in futex_waitv list */ -#define FUTEXV_WAITER_MASK (FUTEX_32 | FUTEX_PRIVATE_FLAG) - /** * futex_parse_waitv - Parse a waitv array from userspace * @futexv: Kernel side list of waiters to be filled * @uwaitv: Userspace list to be parsed * @nr_futexes: Length of futexv + * @wake: Wake to call when futex is woken + * @wake_data: Data for the wake handler * * Return: Error code on failure, 0 on success */ -static int futex_parse_waitv(struct futex_vector *futexv, - struct futex_waitv __user *uwaitv, - unsigned int nr_futexes) +int futex_parse_waitv(struct futex_vector *futexv, + struct futex_waitv __user *uwaitv, + unsigned int nr_futexes, futex_wake_fn *wake, + void *wake_data) { struct futex_waitv aux; unsigned int i; for (i = 0; i < nr_futexes; i++) { + unsigned int flags; + if (copy_from_user(&aux, &uwaitv[i], sizeof(aux))) return -EFAULT; - if ((aux.flags & ~FUTEXV_WAITER_MASK) || aux.__reserved) + if ((aux.flags & ~FUTEX2_VALID_MASK) || aux.__reserved) + return -EINVAL; + + flags = futex2_to_flags(aux.flags); + if (!futex_flags_valid(flags)) return -EINVAL; - if (!(aux.flags & FUTEX_32)) + if (!futex_validate_input(flags, aux.val)) return -EINVAL; - futexv[i].w.flags = aux.flags; + futexv[i].w.flags = flags; futexv[i].w.val = aux.val; futexv[i].w.uaddr = aux.uaddr; futexv[i].q = futex_q_init; + futexv[i].q.wake = wake; + futexv[i].q.wake_data = wake_data; } return 0; } +static int futex2_setup_timeout(struct __kernel_timespec __user *timeout, + clockid_t clockid, struct hrtimer_sleeper *to) +{ + int flag_clkid = 0, flag_init = 0; + struct timespec64 ts; + ktime_t time; + int ret; + + if (!timeout) + return 0; + + if (clockid == CLOCK_REALTIME) { + flag_clkid = FLAGS_CLOCKRT; + flag_init = FUTEX_CLOCK_REALTIME; + } + + if (clockid != CLOCK_REALTIME && clockid != CLOCK_MONOTONIC) + return -EINVAL; + + if (get_timespec64(&ts, timeout)) + return -EFAULT; + + /* + * Since there's no opcode for futex_waitv, use + * FUTEX_WAIT_BITSET that uses absolute timeout as well + */ + ret = futex_init_timeout(FUTEX_WAIT_BITSET, flag_init, &ts, &time); + if (ret) + return ret; + + futex_setup_timer(&time, to, flag_clkid, 0); + return 0; +} + +static inline void futex2_destroy_timeout(struct hrtimer_sleeper *to) +{ + hrtimer_cancel(&to->timer); + destroy_hrtimer_on_stack(&to->timer); +} + /** * sys_futex_waitv - Wait on a list of futexes * @waiters: List of futexes to wait on @@ -249,8 +293,6 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters, { struct hrtimer_sleeper to; struct futex_vector *futexv; - struct timespec64 ts; - ktime_t time; int ret; /* This syscall supports no flags for now */ @@ -260,30 +302,8 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters, if (!nr_futexes || nr_futexes > FUTEX_WAITV_MAX || !waiters) return -EINVAL; - if (timeout) { - int flag_clkid = 0, flag_init = 0; - - if (clockid == CLOCK_REALTIME) { - flag_clkid = FLAGS_CLOCKRT; - flag_init = FUTEX_CLOCK_REALTIME; - } - - if (clockid != CLOCK_REALTIME && clockid != CLOCK_MONOTONIC) - return -EINVAL; - - if (get_timespec64(&ts, timeout)) - return -EFAULT; - - /* - * Since there's no opcode for futex_waitv, use - * FUTEX_WAIT_BITSET that uses absolute timeout as well - */ - ret = futex_init_timeout(FUTEX_WAIT_BITSET, flag_init, &ts, &time); - if (ret) - return ret; - - futex_setup_timer(&time, &to, flag_clkid, 0); - } + if (timeout && (ret = futex2_setup_timeout(timeout, clockid, &to))) + return ret; futexv = kcalloc(nr_futexes, sizeof(*futexv), GFP_KERNEL); if (!futexv) { @@ -291,20 +311,133 @@ SYSCALL_DEFINE5(futex_waitv, struct futex_waitv __user *, waiters, goto destroy_timer; } - ret = futex_parse_waitv(futexv, waiters, nr_futexes); + ret = futex_parse_waitv(futexv, waiters, nr_futexes, futex_wake_mark, + NULL); if (!ret) ret = futex_wait_multiple(futexv, nr_futexes, timeout ? &to : NULL); kfree(futexv); destroy_timer: - if (timeout) { - hrtimer_cancel(&to.timer); - destroy_hrtimer_on_stack(&to.timer); - } + if (timeout) + futex2_destroy_timeout(&to); return ret; } +/* + * sys_futex_wake - Wake a number of futexes + * @uaddr: Address of the futex(es) to wake + * @mask: bitmask + * @nr: Number of the futexes to wake + * @flags: FUTEX2 flags + * + * Identical to the traditional FUTEX_WAKE_BITSET op, except it is part of the + * futex2 family of calls. + */ + +SYSCALL_DEFINE4(futex_wake, + void __user *, uaddr, + unsigned long, mask, + int, nr, + unsigned int, flags) +{ + if (flags & ~FUTEX2_VALID_MASK) + return -EINVAL; + + flags = futex2_to_flags(flags); + if (!futex_flags_valid(flags)) + return -EINVAL; + + if (!futex_validate_input(flags, mask)) + return -EINVAL; + + return futex_wake(uaddr, FLAGS_STRICT | flags, nr, mask); +} + +/* + * sys_futex_wait - Wait on a futex + * @uaddr: Address of the futex to wait on + * @val: Value of @uaddr + * @mask: bitmask + * @flags: FUTEX2 flags + * @timeout: Optional absolute timeout + * @clockid: Clock to be used for the timeout, realtime or monotonic + * + * Identical to the traditional FUTEX_WAIT_BITSET op, except it is part of the + * futex2 familiy of calls. + */ + +SYSCALL_DEFINE6(futex_wait, + void __user *, uaddr, + unsigned long, val, + unsigned long, mask, + unsigned int, flags, + struct __kernel_timespec __user *, timeout, + clockid_t, clockid) +{ + struct hrtimer_sleeper to; + int ret; + + if (flags & ~FUTEX2_VALID_MASK) + return -EINVAL; + + flags = futex2_to_flags(flags); + if (!futex_flags_valid(flags)) + return -EINVAL; + + if (!futex_validate_input(flags, val) || + !futex_validate_input(flags, mask)) + return -EINVAL; + + if (timeout && (ret = futex2_setup_timeout(timeout, clockid, &to))) + return ret; + + ret = __futex_wait(uaddr, flags, val, timeout ? &to : NULL, mask); + + if (timeout) + futex2_destroy_timeout(&to); + + return ret; +} + +/* + * sys_futex_requeue - Requeue a waiter from one futex to another + * @waiters: array describing the source and destination futex + * @flags: unused + * @nr_wake: number of futexes to wake + * @nr_requeue: number of futexes to requeue + * + * Identical to the traditional FUTEX_CMP_REQUEUE op, except it is part of the + * futex2 family of calls. + */ + +SYSCALL_DEFINE4(futex_requeue, + struct futex_waitv __user *, waiters, + unsigned int, flags, + int, nr_wake, + int, nr_requeue) +{ + struct futex_vector futexes[2]; + u32 cmpval; + int ret; + + if (flags) + return -EINVAL; + + if (!waiters) + return -EINVAL; + + ret = futex_parse_waitv(futexes, waiters, 2, futex_wake_mark, NULL); + if (ret) + return ret; + + cmpval = futexes[0].w.val; + + return futex_requeue(u64_to_user_ptr(futexes[0].w.uaddr), futexes[0].w.flags, + u64_to_user_ptr(futexes[1].w.uaddr), futexes[1].w.flags, + nr_wake, nr_requeue, &cmpval, 0); +} + #ifdef CONFIG_COMPAT COMPAT_SYSCALL_DEFINE2(set_robust_list, struct compat_robust_list_head __user *, head, diff --git a/kernel/futex/waitwake.c b/kernel/futex/waitwake.c index ba01b94082..61b112897a 100644 --- a/kernel/futex/waitwake.c +++ b/kernel/futex/waitwake.c @@ -106,20 +106,11 @@ * double_lock_hb() and double_unlock_hb(), respectively. */ -/* - * The hash bucket lock must be held when this is called. - * Afterwards, the futex_q must not be accessed. Callers - * must ensure to later call wake_up_q() for the actual - * wakeups to occur. - */ -void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) +bool __futex_wake_mark(struct futex_q *q) { - struct task_struct *p = q->task; - if (WARN(q->pi_state || q->rt_waiter, "refusing to wake PI futex\n")) - return; + return false; - get_task_struct(p); __futex_unqueue(q); /* * The waiting task can free the futex_q as soon as q->lock_ptr = NULL @@ -130,6 +121,26 @@ void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) */ smp_store_release(&q->lock_ptr, NULL); + return true; +} + +/* + * The hash bucket lock must be held when this is called. + * Afterwards, the futex_q must not be accessed. Callers + * must ensure to later call wake_up_q() for the actual + * wakeups to occur. + */ +void futex_wake_mark(struct wake_q_head *wake_q, struct futex_q *q) +{ + struct task_struct *p = q->task; + + get_task_struct(p); + + if (!__futex_wake_mark(q)) { + put_task_struct(p); + return; + } + /* * Queue the task for later wakeup for after we've released * the hb->lock. @@ -145,16 +156,19 @@ int futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) struct futex_hash_bucket *hb; struct futex_q *this, *next; union futex_key key = FUTEX_KEY_INIT; - int ret; DEFINE_WAKE_Q(wake_q); + int ret; if (!bitset) return -EINVAL; - ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &key, FUTEX_READ); + ret = get_futex_key(uaddr, flags, &key, FUTEX_READ); if (unlikely(ret != 0)) return ret; + if ((flags & FLAGS_STRICT) && !nr_wake) + return 0; + hb = futex_hash(&key); /* Make sure we really have tasks to wakeup */ @@ -174,7 +188,7 @@ int futex_wake(u32 __user *uaddr, unsigned int flags, int nr_wake, u32 bitset) if (!(this->bitset & bitset)) continue; - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++ret >= nr_wake) break; } @@ -245,10 +259,10 @@ int futex_wake_op(u32 __user *uaddr1, unsigned int flags, u32 __user *uaddr2, DEFINE_WAKE_Q(wake_q); retry: - ret = get_futex_key(uaddr1, flags & FLAGS_SHARED, &key1, FUTEX_READ); + ret = get_futex_key(uaddr1, flags, &key1, FUTEX_READ); if (unlikely(ret != 0)) return ret; - ret = get_futex_key(uaddr2, flags & FLAGS_SHARED, &key2, FUTEX_WRITE); + ret = get_futex_key(uaddr2, flags, &key2, FUTEX_WRITE); if (unlikely(ret != 0)) return ret; @@ -289,7 +303,7 @@ retry_private: ret = -EINVAL; goto out_unlock; } - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++ret >= nr_wake) break; } @@ -303,7 +317,7 @@ retry_private: ret = -EINVAL; goto out_unlock; } - futex_wake_mark(&wake_q, this); + this->wake(&wake_q, this); if (++op_ret >= nr_wake2) break; } @@ -358,7 +372,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, } /** - * unqueue_multiple - Remove various futexes from their hash bucket + * futex_unqueue_multiple - Remove various futexes from their hash bucket * @v: The list of futexes to unqueue * @count: Number of futexes in the list * @@ -368,7 +382,7 @@ void futex_wait_queue(struct futex_hash_bucket *hb, struct futex_q *q, * - >=0 - Index of the last futex that was awoken; * - -1 - No futex was awoken */ -static int unqueue_multiple(struct futex_vector *v, int count) +int futex_unqueue_multiple(struct futex_vector *v, int count) { int ret = -1, i; @@ -396,7 +410,7 @@ static int unqueue_multiple(struct futex_vector *v, int count) * - 0 - Success * - <0 - -EFAULT, -EWOULDBLOCK or -EINVAL */ -static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken) +int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *woken) { struct futex_hash_bucket *hb; bool retry = false; @@ -419,11 +433,11 @@ static int futex_wait_multiple_setup(struct futex_vector *vs, int count, int *wo */ retry: for (i = 0; i < count; i++) { - if ((vs[i].w.flags & FUTEX_PRIVATE_FLAG) && retry) + if (!(vs[i].w.flags & FLAGS_SHARED) && retry) continue; ret = get_futex_key(u64_to_user_ptr(vs[i].w.uaddr), - !(vs[i].w.flags & FUTEX_PRIVATE_FLAG), + vs[i].w.flags, &vs[i].q.key, FUTEX_READ); if (unlikely(ret)) @@ -435,7 +449,7 @@ retry: for (i = 0; i < count; i++) { u32 __user *uaddr = (u32 __user *)(unsigned long)vs[i].w.uaddr; struct futex_q *q = &vs[i].q; - u32 val = (u32)vs[i].w.val; + u32 val = vs[i].w.val; hb = futex_q_lock(q); ret = futex_get_value_locked(&uval, uaddr); @@ -458,7 +472,7 @@ retry: * was woken, we don't return error and return this index to * userspace */ - *woken = unqueue_multiple(vs, i); + *woken = futex_unqueue_multiple(vs, i); if (*woken >= 0) return 1; @@ -543,7 +557,7 @@ int futex_wait_multiple(struct futex_vector *vs, unsigned int count, __set_current_state(TASK_RUNNING); - ret = unqueue_multiple(vs, count); + ret = futex_unqueue_multiple(vs, count); if (ret >= 0) return ret; @@ -599,7 +613,7 @@ int futex_wait_setup(u32 __user *uaddr, u32 val, unsigned int flags, * while the syscall executes. */ retry: - ret = get_futex_key(uaddr, flags & FLAGS_SHARED, &q->key, FUTEX_READ); + ret = get_futex_key(uaddr, flags, &q->key, FUTEX_READ); if (unlikely(ret != 0)) return ret; @@ -629,20 +643,18 @@ retry_private: return ret; } -int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset) +int __futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, + struct hrtimer_sleeper *to, u32 bitset) { - struct hrtimer_sleeper timeout, *to; - struct restart_block *restart; - struct futex_hash_bucket *hb; struct futex_q q = futex_q_init; + struct futex_hash_bucket *hb; int ret; if (!bitset) return -EINVAL; + q.bitset = bitset; - to = futex_setup_timer(abs_time, &timeout, flags, - current->timer_slack_ns); retry: /* * Prepare to wait on uaddr. On success, it holds hb->lock and q @@ -650,18 +662,17 @@ retry: */ ret = futex_wait_setup(uaddr, val, flags, &q, &hb); if (ret) - goto out; + return ret; /* futex_queue and wait for wakeup, timeout, or a signal. */ futex_wait_queue(hb, &q, to); /* If we were woken (and unqueued), we succeeded, whatever. */ - ret = 0; if (!futex_unqueue(&q)) - goto out; - ret = -ETIMEDOUT; + return 0; + if (to && !to->task) - goto out; + return -ETIMEDOUT; /* * We expect signal_pending(current), but we might be the @@ -670,24 +681,38 @@ retry: if (!signal_pending(current)) goto retry; - ret = -ERESTARTSYS; - if (!abs_time) - goto out; + return -ERESTARTSYS; +} - restart = ¤t->restart_block; - restart->futex.uaddr = uaddr; - restart->futex.val = val; - restart->futex.time = *abs_time; - restart->futex.bitset = bitset; - restart->futex.flags = flags | FLAGS_HAS_TIMEOUT; +int futex_wait(u32 __user *uaddr, unsigned int flags, u32 val, ktime_t *abs_time, u32 bitset) +{ + struct hrtimer_sleeper timeout, *to; + struct restart_block *restart; + int ret; - ret = set_restart_fn(restart, futex_wait_restart); + to = futex_setup_timer(abs_time, &timeout, flags, + current->timer_slack_ns); -out: - if (to) { - hrtimer_cancel(&to->timer); - destroy_hrtimer_on_stack(&to->timer); + ret = __futex_wait(uaddr, flags, val, to, bitset); + + /* No timeout, nothing to clean up. */ + if (!to) + return ret; + + hrtimer_cancel(&to->timer); + destroy_hrtimer_on_stack(&to->timer); + + if (ret == -ERESTARTSYS) { + restart = ¤t->restart_block; + restart->futex.uaddr = uaddr; + restart->futex.val = val; + restart->futex.time = *abs_time; + restart->futex.bitset = bitset; + restart->futex.flags = flags | FLAGS_HAS_TIMEOUT; + + return set_restart_fn(restart, futex_wait_restart); } + return ret; } diff --git a/kernel/gcov/fs.c b/kernel/gcov/fs.c index 5c3086cad8..01520689b5 100644 --- a/kernel/gcov/fs.c +++ b/kernel/gcov/fs.c @@ -99,7 +99,7 @@ struct gcov_iterator { struct gcov_info *info; size_t size; loff_t pos; - char buffer[]; + char buffer[] __counted_by(size); }; /** diff --git a/kernel/groups.c b/kernel/groups.c index 9aaed2a310..9b43da2264 100644 --- a/kernel/groups.c +++ b/kernel/groups.c @@ -19,7 +19,7 @@ struct group_info *groups_alloc(int gidsetsize) if (!gi) return NULL; - atomic_set(&gi->usage, 1); + refcount_set(&gi->usage, 1); gi->ngroups = gidsetsize; return gi; } diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c index 5a452b94b6..d39a40bc54 100644 --- a/kernel/irq/generic-chip.c +++ b/kernel/irq/generic-chip.c @@ -219,11 +219,15 @@ void irq_init_generic_chip(struct irq_chip_generic *gc, const char *name, int num_ct, unsigned int irq_base, void __iomem *reg_base, irq_flow_handler_t handler) { + struct irq_chip_type *ct = gc->chip_types; + int i; + raw_spin_lock_init(&gc->lock); gc->num_ct = num_ct; gc->irq_base = irq_base; gc->reg_base = reg_base; - gc->chip_types->chip.name = name; + for (i = 0; i < num_ct; i++) + ct[i].chip.name = name; gc->chip_types->handler = handler; } diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c index d309ba84e0..1782f90cd8 100644 --- a/kernel/irq/manage.c +++ b/kernel/irq/manage.c @@ -1852,15 +1852,13 @@ out_thread: struct task_struct *t = new->thread; new->thread = NULL; - kthread_stop(t); - put_task_struct(t); + kthread_stop_put(t); } if (new->secondary && new->secondary->thread) { struct task_struct *t = new->secondary->thread; new->secondary->thread = NULL; - kthread_stop(t); - put_task_struct(t); + kthread_stop_put(t); } out_mput: module_put(desc->owner); @@ -1971,12 +1969,9 @@ static struct irqaction *__free_irq(struct irq_desc *desc, void *dev_id) * the same bit to a newly requested action. */ if (action->thread) { - kthread_stop(action->thread); - put_task_struct(action->thread); - if (action->secondary && action->secondary->thread) { - kthread_stop(action->secondary->thread); - put_task_struct(action->secondary->thread); - } + kthread_stop_put(action->thread); + if (action->secondary && action->secondary->thread) + kthread_stop_put(action->secondary->thread); } /* Last action releases resources */ diff --git a/kernel/kcmp.c b/kernel/kcmp.c index 5353edfad8..b0639f2104 100644 --- a/kernel/kcmp.c +++ b/kernel/kcmp.c @@ -64,8 +64,10 @@ get_file_raw_ptr(struct task_struct *task, unsigned int idx) struct file *file; rcu_read_lock(); - file = task_lookup_fd_rcu(task, idx); + file = task_lookup_fdget_rcu(task, idx); rcu_read_unlock(); + if (file) + fput(file); return file; } diff --git a/kernel/kcsan/kcsan_test.c b/kernel/kcsan/kcsan_test.c index 0ddbdab590..0155862178 100644 --- a/kernel/kcsan/kcsan_test.c +++ b/kernel/kcsan/kcsan_test.c @@ -699,12 +699,9 @@ static void test_barrier_nothreads(struct kunit *test) KCSAN_EXPECT_RW_BARRIER(spin_unlock(&test_spinlock), true); KCSAN_EXPECT_RW_BARRIER(mutex_lock(&test_mutex), false); KCSAN_EXPECT_RW_BARRIER(mutex_unlock(&test_mutex), true); - -#ifdef clear_bit_unlock_is_negative_byte - KCSAN_EXPECT_READ_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true); - KCSAN_EXPECT_WRITE_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true); - KCSAN_EXPECT_RW_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var), true); -#endif + KCSAN_EXPECT_READ_BARRIER(xor_unlock_is_negative_byte(1, &test_var), true); + KCSAN_EXPECT_WRITE_BARRIER(xor_unlock_is_negative_byte(1, &test_var), true); + KCSAN_EXPECT_RW_BARRIER(xor_unlock_is_negative_byte(1, &test_var), true); kcsan_nestable_atomic_end(); } diff --git a/kernel/kcsan/selftest.c b/kernel/kcsan/selftest.c index 8679322450..84a1200271 100644 --- a/kernel/kcsan/selftest.c +++ b/kernel/kcsan/selftest.c @@ -227,12 +227,9 @@ static bool __init test_barrier(void) KCSAN_CHECK_RW_BARRIER(arch_spin_unlock(&arch_spinlock)); spin_lock(&test_spinlock); KCSAN_CHECK_RW_BARRIER(spin_unlock(&test_spinlock)); - -#ifdef clear_bit_unlock_is_negative_byte - KCSAN_CHECK_RW_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var)); - KCSAN_CHECK_READ_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var)); - KCSAN_CHECK_WRITE_BARRIER(clear_bit_unlock_is_negative_byte(0, &test_var)); -#endif + KCSAN_CHECK_RW_BARRIER(xor_unlock_is_negative_byte(1, &test_var)); + KCSAN_CHECK_READ_BARRIER(xor_unlock_is_negative_byte(1, &test_var)); + KCSAN_CHECK_WRITE_BARRIER(xor_unlock_is_negative_byte(1, &test_var)); kcsan_nestable_atomic_end(); return ret; diff --git a/kernel/kexec_core.c b/kernel/kexec_core.c index b7246b7171..b926c4db8a 100644 --- a/kernel/kexec_core.c +++ b/kernel/kexec_core.c @@ -52,23 +52,6 @@ atomic_t __kexec_lock = ATOMIC_INIT(0); /* Flag to indicate we are going to kexec a new kernel */ bool kexec_in_progress = false; - -/* Location of the reserved area for the crash kernel */ -struct resource crashk_res = { - .name = "Crash kernel", - .start = 0, - .end = 0, - .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, - .desc = IORES_DESC_CRASH_KERNEL -}; -struct resource crashk_low_res = { - .name = "Crash kernel", - .start = 0, - .end = 0, - .flags = IORESOURCE_BUSY | IORESOURCE_SYSTEM_RAM, - .desc = IORES_DESC_CRASH_KERNEL -}; - int kexec_should_crash(struct task_struct *p) { /* diff --git a/kernel/kprobes.c b/kernel/kprobes.c index b486504766..d5a0ee40bf 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -1877,13 +1877,27 @@ static struct notifier_block kprobe_exceptions_nb = { #ifdef CONFIG_KRETPROBES #if !defined(CONFIG_KRETPROBE_ON_RETHOOK) + +/* callbacks for objpool of kretprobe instances */ +static int kretprobe_init_inst(void *nod, void *context) +{ + struct kretprobe_instance *ri = nod; + + ri->rph = context; + return 0; +} +static int kretprobe_fini_pool(struct objpool_head *head, void *context) +{ + kfree(context); + return 0; +} + static void free_rp_inst_rcu(struct rcu_head *head) { struct kretprobe_instance *ri = container_of(head, struct kretprobe_instance, rcu); + struct kretprobe_holder *rph = ri->rph; - if (refcount_dec_and_test(&ri->rph->ref)) - kfree(ri->rph); - kfree(ri); + objpool_drop(ri, &rph->pool); } NOKPROBE_SYMBOL(free_rp_inst_rcu); @@ -1892,7 +1906,7 @@ static void recycle_rp_inst(struct kretprobe_instance *ri) struct kretprobe *rp = get_kretprobe(ri); if (likely(rp)) - freelist_add(&ri->freelist, &rp->freelist); + objpool_push(ri, &rp->rph->pool); else call_rcu(&ri->rcu, free_rp_inst_rcu); } @@ -1929,23 +1943,12 @@ NOKPROBE_SYMBOL(kprobe_flush_task); static inline void free_rp_inst(struct kretprobe *rp) { - struct kretprobe_instance *ri; - struct freelist_node *node; - int count = 0; - - node = rp->freelist.head; - while (node) { - ri = container_of(node, struct kretprobe_instance, freelist); - node = node->next; - - kfree(ri); - count++; - } + struct kretprobe_holder *rph = rp->rph; - if (refcount_sub_and_test(count, &rp->rph->ref)) { - kfree(rp->rph); - rp->rph = NULL; - } + if (!rph) + return; + rp->rph = NULL; + objpool_fini(&rph->pool); } /* This assumes the 'tsk' is the current task or the is not running. */ @@ -2087,19 +2090,17 @@ NOKPROBE_SYMBOL(__kretprobe_trampoline_handler) static int pre_handler_kretprobe(struct kprobe *p, struct pt_regs *regs) { struct kretprobe *rp = container_of(p, struct kretprobe, kp); + struct kretprobe_holder *rph = rp->rph; struct kretprobe_instance *ri; - struct freelist_node *fn; - fn = freelist_try_get(&rp->freelist); - if (!fn) { + ri = objpool_pop(&rph->pool); + if (!ri) { rp->nmissed++; return 0; } - ri = container_of(fn, struct kretprobe_instance, freelist); - if (rp->entry_handler && rp->entry_handler(ri, regs)) { - freelist_add(&ri->freelist, &rp->freelist); + objpool_push(ri, &rph->pool); return 0; } @@ -2193,7 +2194,6 @@ int kprobe_on_func_entry(kprobe_opcode_t *addr, const char *sym, unsigned long o int register_kretprobe(struct kretprobe *rp) { int ret; - struct kretprobe_instance *inst; int i; void *addr; @@ -2227,19 +2227,12 @@ int register_kretprobe(struct kretprobe *rp) rp->maxactive = max_t(unsigned int, 10, 2*num_possible_cpus()); #ifdef CONFIG_KRETPROBE_ON_RETHOOK - rp->rh = rethook_alloc((void *)rp, kretprobe_rethook_handler); - if (!rp->rh) - return -ENOMEM; + rp->rh = rethook_alloc((void *)rp, kretprobe_rethook_handler, + sizeof(struct kretprobe_instance) + + rp->data_size, rp->maxactive); + if (IS_ERR(rp->rh)) + return PTR_ERR(rp->rh); - for (i = 0; i < rp->maxactive; i++) { - inst = kzalloc(struct_size(inst, data, rp->data_size), GFP_KERNEL); - if (inst == NULL) { - rethook_free(rp->rh); - rp->rh = NULL; - return -ENOMEM; - } - rethook_add_node(rp->rh, &inst->node); - } rp->nmissed = 0; /* Establish function entry probe point */ ret = register_kprobe(&rp->kp); @@ -2248,24 +2241,18 @@ int register_kretprobe(struct kretprobe *rp) rp->rh = NULL; } #else /* !CONFIG_KRETPROBE_ON_RETHOOK */ - rp->freelist.head = NULL; rp->rph = kzalloc(sizeof(struct kretprobe_holder), GFP_KERNEL); if (!rp->rph) return -ENOMEM; - rcu_assign_pointer(rp->rph->rp, rp); - for (i = 0; i < rp->maxactive; i++) { - inst = kzalloc(struct_size(inst, data, rp->data_size), GFP_KERNEL); - if (inst == NULL) { - refcount_set(&rp->rph->ref, i); - free_rp_inst(rp); - return -ENOMEM; - } - inst->rph = rp->rph; - freelist_add(&inst->freelist, &rp->freelist); + if (objpool_init(&rp->rph->pool, rp->maxactive, rp->data_size + + sizeof(struct kretprobe_instance), GFP_KERNEL, + rp->rph, kretprobe_init_inst, kretprobe_fini_pool)) { + kfree(rp->rph); + rp->rph = NULL; + return -ENOMEM; } - refcount_set(&rp->rph->ref, i); - + rcu_assign_pointer(rp->rph->rp, rp); rp->nmissed = 0; /* Establish function entry probe point */ ret = register_kprobe(&rp->kp); diff --git a/kernel/kthread.c b/kernel/kthread.c index 1eea53050b..c5e40830c1 100644 --- a/kernel/kthread.c +++ b/kernel/kthread.c @@ -715,6 +715,24 @@ int kthread_stop(struct task_struct *k) } EXPORT_SYMBOL(kthread_stop); +/** + * kthread_stop_put - stop a thread and put its task struct + * @k: thread created by kthread_create(). + * + * Stops a thread created by kthread_create() and put its task_struct. + * Only use when holding an extra task struct reference obtained by + * calling get_task_struct(). + */ +int kthread_stop_put(struct task_struct *k) +{ + int ret; + + ret = kthread_stop(k); + put_task_struct(k); + return ret; +} +EXPORT_SYMBOL(kthread_stop_put); + int kthreadd(void *unused) { struct task_struct *tsk = current; @@ -1469,7 +1487,6 @@ void kthread_unuse_mm(struct mm_struct *mm) * clearing tsk->mm. */ smp_mb__after_spinlock(); - sync_mm_rss(mm); local_irq_disable(); tsk->mm = NULL; membarrier_update_current_mm(NULL); diff --git a/kernel/locking/lock_events.c b/kernel/locking/lock_events.c index fa2c2f951c..e68d820995 100644 --- a/kernel/locking/lock_events.c +++ b/kernel/locking/lock_events.c @@ -146,7 +146,7 @@ static int __init init_lockevent_counts(void) struct dentry *d_counts = debugfs_create_dir(LOCK_EVENTS_DIR, NULL); int i; - if (!d_counts) + if (IS_ERR(d_counts)) goto out; /* @@ -159,14 +159,14 @@ static int __init init_lockevent_counts(void) for (i = 0; i < lockevent_num; i++) { if (skip_lockevent(lockevent_names[i])) continue; - if (!debugfs_create_file(lockevent_names[i], 0400, d_counts, - (void *)(long)i, &fops_lockevent)) + if (IS_ERR(debugfs_create_file(lockevent_names[i], 0400, d_counts, + (void *)(long)i, &fops_lockevent))) goto fail_undo; } - if (!debugfs_create_file(lockevent_names[LOCKEVENT_reset_cnts], 0200, + if (IS_ERR(debugfs_create_file(lockevent_names[LOCKEVENT_reset_cnts], 0200, d_counts, (void *)(long)LOCKEVENT_reset_cnts, - &fops_lockevent)) + &fops_lockevent))) goto fail_undo; return 0; diff --git a/kernel/locking/lockdep_proc.c b/kernel/locking/lockdep_proc.c index 15fdc7fa5c..e2bfb1db58 100644 --- a/kernel/locking/lockdep_proc.c +++ b/kernel/locking/lockdep_proc.c @@ -440,7 +440,7 @@ static void snprint_time(char *buf, size_t bufsiz, s64 nr) static void seq_time(struct seq_file *m, s64 time) { - char num[15]; + char num[22]; snprint_time(num, sizeof(num), time); seq_printf(m, " %14s", num); diff --git a/kernel/locking/locktorture.c b/kernel/locking/locktorture.c index 270c7f80ce..69d3cd2cfc 100644 --- a/kernel/locking/locktorture.c +++ b/kernel/locking/locktorture.c @@ -33,21 +33,23 @@ MODULE_LICENSE("GPL"); MODULE_AUTHOR("Paul E. McKenney <paulmck@linux.ibm.com>"); -torture_param(int, nwriters_stress, -1, "Number of write-locking stress-test threads"); -torture_param(int, nreaders_stress, -1, "Number of read-locking stress-test threads"); +torture_param(int, acq_writer_lim, 0, "Write_acquisition time limit (jiffies)."); +torture_param(int, call_rcu_chains, 0, "Self-propagate call_rcu() chains during test (0=disable)."); torture_param(int, long_hold, 100, "Do occasional long hold of lock (ms), 0=disable"); +torture_param(int, nested_locks, 0, "Number of nested locks (max = 8)"); +torture_param(int, nreaders_stress, -1, "Number of read-locking stress-test threads"); +torture_param(int, nwriters_stress, -1, "Number of write-locking stress-test threads"); torture_param(int, onoff_holdoff, 0, "Time after boot before CPU hotplugs (s)"); torture_param(int, onoff_interval, 0, "Time between CPU hotplugs (s), 0=disable"); +torture_param(int, rt_boost, 2, + "Do periodic rt-boost. 0=Disable, 1=Only for rt_mutex, 2=For all lock types."); +torture_param(int, rt_boost_factor, 50, "A factor determining how often rt-boost happens."); torture_param(int, shuffle_interval, 3, "Number of jiffies between shuffles, 0=disable"); torture_param(int, shutdown_secs, 0, "Shutdown time (j), <= zero to disable."); torture_param(int, stat_interval, 60, "Number of seconds between stats printk()s"); torture_param(int, stutter, 5, "Number of jiffies to run/halt test, 0=disable"); -torture_param(int, rt_boost, 2, - "Do periodic rt-boost. 0=Disable, 1=Only for rt_mutex, 2=For all lock types."); -torture_param(int, rt_boost_factor, 50, "A factor determining how often rt-boost happens."); -torture_param(int, writer_fifo, 0, "Run writers at sched_set_fifo() priority"); torture_param(int, verbose, 1, "Enable verbose debugging printk()s"); -torture_param(int, nested_locks, 0, "Number of nested locks (max = 8)"); +torture_param(int, writer_fifo, 0, "Run writers at sched_set_fifo() priority"); /* Going much higher trips "BUG: MAX_LOCKDEP_CHAIN_HLOCKS too low!" errors */ #define MAX_NESTED_LOCKS 8 @@ -56,6 +58,55 @@ module_param(torture_type, charp, 0444); MODULE_PARM_DESC(torture_type, "Type of lock to torture (spin_lock, spin_lock_irq, mutex_lock, ...)"); +static cpumask_var_t bind_readers; // Bind the readers to the specified set of CPUs. +static cpumask_var_t bind_writers; // Bind the writers to the specified set of CPUs. + +// Parse a cpumask kernel parameter. If there are more users later on, +// this might need to got to a more central location. +static int param_set_cpumask(const char *val, const struct kernel_param *kp) +{ + cpumask_var_t *cm_bind = kp->arg; + int ret; + char *s; + + if (!alloc_cpumask_var(cm_bind, GFP_KERNEL)) { + s = "Out of memory"; + ret = -ENOMEM; + goto out_err; + } + ret = cpulist_parse(val, *cm_bind); + if (!ret) + return ret; + s = "Bad CPU range"; +out_err: + pr_warn("%s: %s, all CPUs set\n", kp->name, s); + cpumask_setall(*cm_bind); + return ret; +} + +// Output a cpumask kernel parameter. +static int param_get_cpumask(char *buffer, const struct kernel_param *kp) +{ + cpumask_var_t *cm_bind = kp->arg; + + return sprintf(buffer, "%*pbl", cpumask_pr_args(*cm_bind)); +} + +static bool cpumask_nonempty(cpumask_var_t mask) +{ + return cpumask_available(mask) && !cpumask_empty(mask); +} + +static const struct kernel_param_ops lt_bind_ops = { + .set = param_set_cpumask, + .get = param_get_cpumask, +}; + +module_param_cb(bind_readers, <_bind_ops, &bind_readers, 0644); +module_param_cb(bind_writers, <_bind_ops, &bind_writers, 0644); + +long torture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask); + static struct task_struct *stats_task; static struct task_struct **writer_tasks; static struct task_struct **reader_tasks; @@ -69,6 +120,12 @@ struct lock_stress_stats { long n_lock_acquired; }; +struct call_rcu_chain { + struct rcu_head crc_rh; + bool crc_stop; +}; +struct call_rcu_chain *call_rcu_chain; + /* Forward reference. */ static void lock_torture_cleanup(void); @@ -116,12 +173,9 @@ static int torture_lock_busted_write_lock(int tid __maybe_unused) static void torture_lock_busted_write_delay(struct torture_random_state *trsp) { - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; - /* We want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms); + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) + mdelay(long_hold); if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) torture_preempt_schedule(); /* Allow test to be preempted. */ } @@ -194,15 +248,14 @@ __acquires(torture_spinlock) static void torture_spin_lock_write_delay(struct torture_random_state *trsp) { const unsigned long shortdelay_us = 2; - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; unsigned long j; /* We want a short delay mostly to emulate likely code, and * we want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * longdelay_ms))) { + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) { j = jiffies; - mdelay(longdelay_ms); + mdelay(long_hold); pr_alert("%s: delay = %lu jiffies.\n", __func__, jiffies - j); } if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 200 * shortdelay_us))) @@ -320,14 +373,12 @@ __acquires(torture_rwlock) static void torture_rwlock_write_delay(struct torture_random_state *trsp) { const unsigned long shortdelay_us = 2; - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; /* We want a short delay mostly to emulate likely code, and * we want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms); + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) + mdelay(long_hold); else udelay(shortdelay_us); } @@ -348,14 +399,12 @@ __acquires(torture_rwlock) static void torture_rwlock_read_delay(struct torture_random_state *trsp) { const unsigned long shortdelay_us = 10; - const unsigned long longdelay_ms = 100; /* We want a short delay mostly to emulate likely code, and * we want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealreaders_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms); + if (long_hold && !(torture_random(trsp) % (cxt.nrealreaders_stress * 2000 * long_hold))) + mdelay(long_hold); else udelay(shortdelay_us); } @@ -453,12 +502,9 @@ __acquires(torture_mutex) static void torture_mutex_delay(struct torture_random_state *trsp) { - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; - /* We want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms * 5); + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) + mdelay(long_hold * 5); if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) torture_preempt_schedule(); /* Allow test to be preempted. */ } @@ -626,15 +672,13 @@ __acquires(torture_rtmutex) static void torture_rtmutex_delay(struct torture_random_state *trsp) { const unsigned long shortdelay_us = 2; - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; /* * We want a short delay mostly to emulate likely code, and * we want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms); + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) + mdelay(long_hold); if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 200 * shortdelay_us))) udelay(shortdelay_us); @@ -691,12 +735,9 @@ __acquires(torture_rwsem) static void torture_rwsem_write_delay(struct torture_random_state *trsp) { - const unsigned long longdelay_ms = long_hold ? long_hold : ULONG_MAX; - /* We want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealwriters_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms * 10); + if (long_hold && !(torture_random(trsp) % (cxt.nrealwriters_stress * 2000 * long_hold))) + mdelay(long_hold * 10); if (!(torture_random(trsp) % (cxt.nrealwriters_stress * 20000))) torture_preempt_schedule(); /* Allow test to be preempted. */ } @@ -716,14 +757,11 @@ __acquires(torture_rwsem) static void torture_rwsem_read_delay(struct torture_random_state *trsp) { - const unsigned long longdelay_ms = 100; - /* We want a long delay occasionally to force massive contention. */ - if (!(torture_random(trsp) % - (cxt.nrealreaders_stress * 2000 * longdelay_ms))) - mdelay(longdelay_ms * 2); + if (long_hold && !(torture_random(trsp) % (cxt.nrealreaders_stress * 2000 * long_hold))) + mdelay(long_hold * 2); else - mdelay(longdelay_ms / 2); + mdelay(long_hold / 2); if (!(torture_random(trsp) % (cxt.nrealreaders_stress * 20000))) torture_preempt_schedule(); /* Allow test to be preempted. */ } @@ -803,11 +841,13 @@ static struct lock_torture_ops percpu_rwsem_lock_ops = { */ static int lock_torture_writer(void *arg) { + unsigned long j; + unsigned long j1; + u32 lockset_mask; struct lock_stress_stats *lwsp = arg; - int tid = lwsp - cxt.lwsa; DEFINE_TORTURE_RANDOM(rand); - u32 lockset_mask; bool skip_main_lock; + int tid = lwsp - cxt.lwsa; VERBOSE_TOROUT_STRING("lock_torture_writer task started"); if (!rt_task(current)) @@ -834,17 +874,24 @@ static int lock_torture_writer(void *arg) cxt.cur_ops->nested_lock(tid, lockset_mask); if (!skip_main_lock) { + if (acq_writer_lim > 0) + j = jiffies; cxt.cur_ops->writelock(tid); if (WARN_ON_ONCE(lock_is_write_held)) lwsp->n_lock_fail++; lock_is_write_held = true; if (WARN_ON_ONCE(atomic_read(&lock_is_read_held))) lwsp->n_lock_fail++; /* rare, but... */ - + if (acq_writer_lim > 0) { + j1 = jiffies; + WARN_ONCE(time_after(j1, j + acq_writer_lim), + "%s: Lock acquisition took %lu jiffies.\n", + __func__, j1 - j); + } lwsp->n_lock_acquired++; - } - if (!skip_main_lock) { + cxt.cur_ops->write_delay(&rand); + lock_is_write_held = false; WRITE_ONCE(last_lock_release, jiffies); cxt.cur_ops->writeunlock(tid); @@ -986,16 +1033,69 @@ static int lock_torture_stats(void *arg) return 0; } + static inline void lock_torture_print_module_parms(struct lock_torture_ops *cur_ops, const char *tag) { + static cpumask_t cpumask_all; + cpumask_t *rcmp = cpumask_nonempty(bind_readers) ? bind_readers : &cpumask_all; + cpumask_t *wcmp = cpumask_nonempty(bind_writers) ? bind_writers : &cpumask_all; + + cpumask_setall(&cpumask_all); pr_alert("%s" TORTURE_FLAG - "--- %s%s: nwriters_stress=%d nreaders_stress=%d nested_locks=%d stat_interval=%d verbose=%d shuffle_interval=%d stutter=%d shutdown_secs=%d onoff_interval=%d onoff_holdoff=%d\n", + "--- %s%s: acq_writer_lim=%d bind_readers=%*pbl bind_writers=%*pbl call_rcu_chains=%d long_hold=%d nested_locks=%d nreaders_stress=%d nwriters_stress=%d onoff_holdoff=%d onoff_interval=%d rt_boost=%d rt_boost_factor=%d shuffle_interval=%d shutdown_secs=%d stat_interval=%d stutter=%d verbose=%d writer_fifo=%d\n", torture_type, tag, cxt.debug_lock ? " [debug]": "", - cxt.nrealwriters_stress, cxt.nrealreaders_stress, - nested_locks, stat_interval, verbose, shuffle_interval, - stutter, shutdown_secs, onoff_interval, onoff_holdoff); + acq_writer_lim, cpumask_pr_args(rcmp), cpumask_pr_args(wcmp), + call_rcu_chains, long_hold, nested_locks, cxt.nrealreaders_stress, + cxt.nrealwriters_stress, onoff_holdoff, onoff_interval, rt_boost, + rt_boost_factor, shuffle_interval, shutdown_secs, stat_interval, stutter, + verbose, writer_fifo); +} + +// If requested, maintain call_rcu() chains to keep a grace period always +// in flight. These increase the probability of getting an RCU CPU stall +// warning and associated diagnostics when a locking primitive stalls. + +static void call_rcu_chain_cb(struct rcu_head *rhp) +{ + struct call_rcu_chain *crcp = container_of(rhp, struct call_rcu_chain, crc_rh); + + if (!smp_load_acquire(&crcp->crc_stop)) { + (void)start_poll_synchronize_rcu(); // Start one grace period... + call_rcu(&crcp->crc_rh, call_rcu_chain_cb); // ... and later start another. + } +} + +// Start the requested number of call_rcu() chains. +static int call_rcu_chain_init(void) +{ + int i; + + if (call_rcu_chains <= 0) + return 0; + call_rcu_chain = kcalloc(call_rcu_chains, sizeof(*call_rcu_chain), GFP_KERNEL); + if (!call_rcu_chain) + return -ENOMEM; + for (i = 0; i < call_rcu_chains; i++) { + call_rcu_chain[i].crc_stop = false; + call_rcu(&call_rcu_chain[i].crc_rh, call_rcu_chain_cb); + } + return 0; +} + +// Stop all of the call_rcu() chains. +static void call_rcu_chain_cleanup(void) +{ + int i; + + if (!call_rcu_chain) + return; + for (i = 0; i < call_rcu_chains; i++) + smp_store_release(&call_rcu_chain[i].crc_stop, true); + rcu_barrier(); + kfree(call_rcu_chain); + call_rcu_chain = NULL; } static void lock_torture_cleanup(void) @@ -1048,6 +1148,8 @@ static void lock_torture_cleanup(void) kfree(cxt.lrsa); cxt.lrsa = NULL; + call_rcu_chain_cleanup(); + end: if (cxt.init_called) { if (cxt.cur_ops->exit) @@ -1177,6 +1279,10 @@ static int __init lock_torture_init(void) } } + firsterr = call_rcu_chain_init(); + if (torture_init_error(firsterr)) + goto unwind; + lock_torture_print_module_parms(cxt.cur_ops, "Start of test"); /* Prepare torture context. */ @@ -1250,6 +1356,8 @@ static int __init lock_torture_init(void) writer_fifo ? sched_set_fifo : NULL); if (torture_init_error(firsterr)) goto unwind; + if (cpumask_nonempty(bind_writers)) + torture_sched_setaffinity(writer_tasks[i]->pid, bind_writers); create_reader: if (cxt.cur_ops->readlock == NULL || (j >= cxt.nrealreaders_stress)) @@ -1259,6 +1367,8 @@ static int __init lock_torture_init(void) reader_tasks[j]); if (torture_init_error(firsterr)) goto unwind; + if (cpumask_nonempty(bind_readers)) + torture_sched_setaffinity(reader_tasks[j]->pid, bind_readers); } if (stat_interval > 0) { firsterr = torture_create_kthread(lock_torture_stats, NULL, diff --git a/kernel/locking/mutex.c b/kernel/locking/mutex.c index d973fe6041..2deeeca3e7 100644 --- a/kernel/locking/mutex.c +++ b/kernel/locking/mutex.c @@ -1126,6 +1126,9 @@ EXPORT_SYMBOL(ww_mutex_lock_interruptible); #endif /* !CONFIG_DEBUG_LOCK_ALLOC */ #endif /* !CONFIG_PREEMPT_RT */ +EXPORT_TRACEPOINT_SYMBOL_GPL(contention_begin); +EXPORT_TRACEPOINT_SYMBOL_GPL(contention_end); + /** * atomic_dec_and_mutex_lock - return holding mutex if we dec to 0 * @cnt: the atomic which we are to dec diff --git a/kernel/locking/osq_lock.c b/kernel/locking/osq_lock.c index d5610ad52b..75a6f61338 100644 --- a/kernel/locking/osq_lock.c +++ b/kernel/locking/osq_lock.c @@ -11,6 +11,13 @@ * called from interrupt context and we have preemption disabled while * spinning. */ + +struct optimistic_spin_node { + struct optimistic_spin_node *next, *prev; + int locked; /* 1 if lock acquired */ + int cpu; /* encoded CPU # + 1 value */ +}; + static DEFINE_PER_CPU_SHARED_ALIGNED(struct optimistic_spin_node, osq_node); /* @@ -37,32 +44,28 @@ static inline struct optimistic_spin_node *decode_cpu(int encoded_cpu_val) /* * Get a stable @node->next pointer, either for unlock() or unqueue() purposes. * Can return NULL in case we were the last queued and we updated @lock instead. + * + * If osq_lock() is being cancelled there must be a previous node + * and 'old_cpu' is its CPU #. + * For osq_unlock() there is never a previous node and old_cpu is + * set to OSQ_UNLOCKED_VAL. */ static inline struct optimistic_spin_node * osq_wait_next(struct optimistic_spin_queue *lock, struct optimistic_spin_node *node, - struct optimistic_spin_node *prev) + int old_cpu) { - struct optimistic_spin_node *next = NULL; int curr = encode_cpu(smp_processor_id()); - int old; - - /* - * If there is a prev node in queue, then the 'old' value will be - * the prev node's CPU #, else it's set to OSQ_UNLOCKED_VAL since if - * we're currently last in queue, then the queue will then become empty. - */ - old = prev ? prev->cpu : OSQ_UNLOCKED_VAL; for (;;) { if (atomic_read(&lock->tail) == curr && - atomic_cmpxchg_acquire(&lock->tail, curr, old) == curr) { + atomic_cmpxchg_acquire(&lock->tail, curr, old_cpu) == curr) { /* * We were the last queued, we moved @lock back. @prev * will now observe @lock and will complete its * unlock()/unqueue(). */ - break; + return NULL; } /* @@ -76,15 +79,15 @@ osq_wait_next(struct optimistic_spin_queue *lock, * wait for a new @node->next from its Step-C. */ if (node->next) { + struct optimistic_spin_node *next; + next = xchg(&node->next, NULL); if (next) - break; + return next; } cpu_relax(); } - - return next; } bool osq_lock(struct optimistic_spin_queue *lock) @@ -186,7 +189,7 @@ bool osq_lock(struct optimistic_spin_queue *lock) * back to @prev. */ - next = osq_wait_next(lock, node, prev); + next = osq_wait_next(lock, node, prev->cpu); if (!next) return false; @@ -226,7 +229,7 @@ void osq_unlock(struct optimistic_spin_queue *lock) return; } - next = osq_wait_next(lock, node, NULL); + next = osq_wait_next(lock, node, OSQ_UNLOCKED_VAL); if (next) WRITE_ONCE(next->locked, 1); } diff --git a/kernel/locking/rtmutex.c b/kernel/locking/rtmutex.c index 21db0df0eb..4a10e8c16f 100644 --- a/kernel/locking/rtmutex.c +++ b/kernel/locking/rtmutex.c @@ -218,6 +218,11 @@ static __always_inline bool rt_mutex_cmpxchg_acquire(struct rt_mutex_base *lock, return try_cmpxchg_acquire(&lock->owner, &old, new); } +static __always_inline bool rt_mutex_try_acquire(struct rt_mutex_base *lock) +{ + return rt_mutex_cmpxchg_acquire(lock, NULL, current); +} + static __always_inline bool rt_mutex_cmpxchg_release(struct rt_mutex_base *lock, struct task_struct *old, struct task_struct *new) @@ -297,6 +302,20 @@ static __always_inline bool rt_mutex_cmpxchg_acquire(struct rt_mutex_base *lock, } +static int __sched rt_mutex_slowtrylock(struct rt_mutex_base *lock); + +static __always_inline bool rt_mutex_try_acquire(struct rt_mutex_base *lock) +{ + /* + * With debug enabled rt_mutex_cmpxchg trylock() will always fail. + * + * Avoid unconditionally taking the slow path by using + * rt_mutex_slow_trylock() which is covered by the debug code and can + * acquire a non-contended rtmutex. + */ + return rt_mutex_slowtrylock(lock); +} + static __always_inline bool rt_mutex_cmpxchg_release(struct rt_mutex_base *lock, struct task_struct *old, struct task_struct *new) @@ -1613,7 +1632,7 @@ static int __sched rt_mutex_slowlock_block(struct rt_mutex_base *lock, raw_spin_unlock_irq(&lock->wait_lock); if (!owner || !rtmutex_spin_on_owner(lock, waiter, owner)) - schedule(); + rt_mutex_schedule(); raw_spin_lock_irq(&lock->wait_lock); set_current_state(state); @@ -1642,7 +1661,7 @@ static void __sched rt_mutex_handle_deadlock(int res, int detect_deadlock, WARN(1, "rtmutex deadlock detected\n"); while (1) { set_current_state(TASK_INTERRUPTIBLE); - schedule(); + rt_mutex_schedule(); } } @@ -1738,6 +1757,15 @@ static int __sched rt_mutex_slowlock(struct rt_mutex_base *lock, int ret; /* + * Do all pre-schedule work here, before we queue a waiter and invoke + * PI -- any such work that trips on rtlock (PREEMPT_RT spinlock) would + * otherwise recurse back into task_blocks_on_rt_mutex() through + * rtlock_slowlock() and will then enqueue a second waiter for this + * same task and things get really confusing real fast. + */ + rt_mutex_pre_schedule(); + + /* * Technically we could use raw_spin_[un]lock_irq() here, but this can * be called in early boot if the cmpxchg() fast path is disabled * (debug, no architecture support). In this case we will acquire the @@ -1748,6 +1776,7 @@ static int __sched rt_mutex_slowlock(struct rt_mutex_base *lock, raw_spin_lock_irqsave(&lock->wait_lock, flags); ret = __rt_mutex_slowlock_locked(lock, ww_ctx, state); raw_spin_unlock_irqrestore(&lock->wait_lock, flags); + rt_mutex_post_schedule(); return ret; } @@ -1755,7 +1784,9 @@ static int __sched rt_mutex_slowlock(struct rt_mutex_base *lock, static __always_inline int __rt_mutex_lock(struct rt_mutex_base *lock, unsigned int state) { - if (likely(rt_mutex_cmpxchg_acquire(lock, NULL, current))) + lockdep_assert(!current->pi_blocked_on); + + if (likely(rt_mutex_try_acquire(lock))) return 0; return rt_mutex_slowlock(lock, NULL, state); diff --git a/kernel/locking/rwbase_rt.c b/kernel/locking/rwbase_rt.c index 25ec023947..34a59569db 100644 --- a/kernel/locking/rwbase_rt.c +++ b/kernel/locking/rwbase_rt.c @@ -71,6 +71,7 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb, struct rt_mutex_base *rtm = &rwb->rtmutex; int ret; + rwbase_pre_schedule(); raw_spin_lock_irq(&rtm->wait_lock); /* @@ -125,12 +126,15 @@ static int __sched __rwbase_read_lock(struct rwbase_rt *rwb, rwbase_rtmutex_unlock(rtm); trace_contention_end(rwb, ret); + rwbase_post_schedule(); return ret; } static __always_inline int rwbase_read_lock(struct rwbase_rt *rwb, unsigned int state) { + lockdep_assert(!current->pi_blocked_on); + if (rwbase_read_trylock(rwb)) return 0; @@ -237,6 +241,8 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb, /* Force readers into slow path */ atomic_sub(READER_BIAS, &rwb->readers); + rwbase_pre_schedule(); + raw_spin_lock_irqsave(&rtm->wait_lock, flags); if (__rwbase_write_trylock(rwb)) goto out_unlock; @@ -248,6 +254,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb, if (rwbase_signal_pending_state(state, current)) { rwbase_restore_current_state(); __rwbase_write_unlock(rwb, 0, flags); + rwbase_post_schedule(); trace_contention_end(rwb, -EINTR); return -EINTR; } @@ -266,6 +273,7 @@ static int __sched rwbase_write_lock(struct rwbase_rt *rwb, out_unlock: raw_spin_unlock_irqrestore(&rtm->wait_lock, flags); + rwbase_post_schedule(); return 0; } diff --git a/kernel/locking/rwsem.c b/kernel/locking/rwsem.c index 9eabd585ce..2340b6d90e 100644 --- a/kernel/locking/rwsem.c +++ b/kernel/locking/rwsem.c @@ -1427,8 +1427,14 @@ static inline void __downgrade_write(struct rw_semaphore *sem) #define rwbase_signal_pending_state(state, current) \ signal_pending_state(state, current) +#define rwbase_pre_schedule() \ + rt_mutex_pre_schedule() + #define rwbase_schedule() \ - schedule() + rt_mutex_schedule() + +#define rwbase_post_schedule() \ + rt_mutex_post_schedule() #include "rwbase_rt.c" diff --git a/kernel/locking/spinlock_rt.c b/kernel/locking/spinlock_rt.c index 48a19ed848..38e292454f 100644 --- a/kernel/locking/spinlock_rt.c +++ b/kernel/locking/spinlock_rt.c @@ -37,6 +37,8 @@ static __always_inline void rtlock_lock(struct rt_mutex_base *rtm) { + lockdep_assert(!current->pi_blocked_on); + if (unlikely(!rt_mutex_cmpxchg_acquire(rtm, NULL, current))) rtlock_slowlock(rtm); } @@ -184,9 +186,13 @@ static __always_inline int rwbase_rtmutex_trylock(struct rt_mutex_base *rtm) #define rwbase_signal_pending_state(state, current) (0) +#define rwbase_pre_schedule() + #define rwbase_schedule() \ schedule_rtlock() +#define rwbase_post_schedule() + #include "rwbase_rt.c" /* * The common functions which get wrapped into the rwlock API. diff --git a/kernel/locking/test-ww_mutex.c b/kernel/locking/test-ww_mutex.c index 7c5a8f0549..78719e1ef1 100644 --- a/kernel/locking/test-ww_mutex.c +++ b/kernel/locking/test-ww_mutex.c @@ -9,7 +9,7 @@ #include <linux/delay.h> #include <linux/kthread.h> #include <linux/module.h> -#include <linux/random.h> +#include <linux/prandom.h> #include <linux/slab.h> #include <linux/ww_mutex.h> @@ -386,6 +386,19 @@ struct stress { int nlocks; }; +struct rnd_state rng; +DEFINE_SPINLOCK(rng_lock); + +static inline u32 prandom_u32_below(u32 ceil) +{ + u32 ret; + + spin_lock(&rng_lock); + ret = prandom_u32_state(&rng) % ceil; + spin_unlock(&rng_lock); + return ret; +} + static int *get_random_order(int count) { int *order; @@ -399,7 +412,7 @@ static int *get_random_order(int count) order[n] = n; for (n = count - 1; n > 1; n--) { - r = get_random_u32_below(n + 1); + r = prandom_u32_below(n + 1); if (r != n) { tmp = order[n]; order[n] = order[r]; @@ -452,17 +465,18 @@ retry: ww_mutex_unlock(&locks[order[n]]); if (err == -EDEADLK) { - ww_mutex_lock_slow(&locks[order[contended]], &ctx); - goto retry; + if (!time_after(jiffies, stress->timeout)) { + ww_mutex_lock_slow(&locks[order[contended]], &ctx); + goto retry; + } } + ww_acquire_fini(&ctx); if (err) { pr_err_once("stress (%s) failed with %d\n", __func__, err); break; } - - ww_acquire_fini(&ctx); } while (!time_after(jiffies, stress->timeout)); kfree(order); @@ -629,6 +643,8 @@ static int __init test_ww_mutex_init(void) printk(KERN_INFO "Beginning ww mutex selftests\n"); + prandom_seed_state(&rng, get_random_u64()); + wq = alloc_workqueue("test-ww_mutex", WQ_UNBOUND, 0); if (!wq) return -ENOMEM; diff --git a/kernel/locking/ww_rt_mutex.c b/kernel/locking/ww_rt_mutex.c index d1473c6241..c7196de838 100644 --- a/kernel/locking/ww_rt_mutex.c +++ b/kernel/locking/ww_rt_mutex.c @@ -62,7 +62,7 @@ __ww_rt_mutex_lock(struct ww_mutex *lock, struct ww_acquire_ctx *ww_ctx, } mutex_acquire_nest(&rtm->dep_map, 0, 0, nest_lock, ip); - if (likely(rt_mutex_cmpxchg_acquire(&rtm->rtmutex, NULL, current))) { + if (likely(rt_mutex_try_acquire(&rtm->rtmutex))) { if (ww_ctx) ww_mutex_set_context_fastpath(lock, ww_ctx); return 0; diff --git a/kernel/module/Kconfig b/kernel/module/Kconfig index 33a2e991f6..0ea1b2970a 100644 --- a/kernel/module/Kconfig +++ b/kernel/module/Kconfig @@ -236,14 +236,6 @@ choice possible to load a signed module containing the algorithm to check the signature on that module. -config MODULE_SIG_SHA1 - bool "Sign modules with SHA-1" - select CRYPTO_SHA1 - -config MODULE_SIG_SHA224 - bool "Sign modules with SHA-224" - select CRYPTO_SHA256 - config MODULE_SIG_SHA256 bool "Sign modules with SHA-256" select CRYPTO_SHA256 @@ -256,16 +248,29 @@ config MODULE_SIG_SHA512 bool "Sign modules with SHA-512" select CRYPTO_SHA512 +config MODULE_SIG_SHA3_256 + bool "Sign modules with SHA3-256" + select CRYPTO_SHA3 + +config MODULE_SIG_SHA3_384 + bool "Sign modules with SHA3-384" + select CRYPTO_SHA3 + +config MODULE_SIG_SHA3_512 + bool "Sign modules with SHA3-512" + select CRYPTO_SHA3 + endchoice config MODULE_SIG_HASH string depends on MODULE_SIG || IMA_APPRAISE_MODSIG - default "sha1" if MODULE_SIG_SHA1 - default "sha224" if MODULE_SIG_SHA224 default "sha256" if MODULE_SIG_SHA256 default "sha384" if MODULE_SIG_SHA384 default "sha512" if MODULE_SIG_SHA512 + default "sha3-256" if MODULE_SIG_SHA3_256 + default "sha3-384" if MODULE_SIG_SHA3_384 + default "sha3-512" if MODULE_SIG_SHA3_512 choice prompt "Module compression mode" diff --git a/kernel/module/stats.c b/kernel/module/stats.c index 6ab2c94d6b..3ba0e98b3c 100644 --- a/kernel/module/stats.c +++ b/kernel/module/stats.c @@ -126,7 +126,7 @@ static LIST_HEAD(dup_failed_modules); * These typically should not happen unless your system is under memory * pressure. * * invalid_becoming_bytes: total number of bytes allocated and freed used - * used to read the kernel module userspace wants us to read before we + * to read the kernel module userspace wants us to read before we * promote it to be processed to be added to our @modules linked list. These * failures can happen if we had a check in between a successful kernel_read_file_from_fd() * call and right before we allocate the our private memory for the module diff --git a/kernel/module/sysfs.c b/kernel/module/sysfs.c index c921bf0440..d964167c66 100644 --- a/kernel/module/sysfs.c +++ b/kernel/module/sysfs.c @@ -143,7 +143,7 @@ static void remove_sect_attrs(struct module *mod) struct module_notes_attrs { struct kobject *dir; unsigned int notes; - struct bin_attribute attrs[]; + struct bin_attribute attrs[] __counted_by(notes); }; static ssize_t module_notes_read(struct file *filp, struct kobject *kobj, diff --git a/kernel/panic.c b/kernel/panic.c index ffa037fa77..2807639aab 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -192,14 +192,15 @@ atomic_t panic_cpu = ATOMIC_INIT(PANIC_CPU_INVALID); */ void nmi_panic(struct pt_regs *regs, const char *msg) { - int old_cpu, cpu; + int old_cpu, this_cpu; - cpu = raw_smp_processor_id(); - old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, cpu); + old_cpu = PANIC_CPU_INVALID; + this_cpu = raw_smp_processor_id(); - if (old_cpu == PANIC_CPU_INVALID) + /* atomic_try_cmpxchg updates old_cpu on failure */ + if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) panic("%s", msg); - else if (old_cpu != cpu) + else if (old_cpu != this_cpu) nmi_panic_self_stop(regs); } EXPORT_SYMBOL(nmi_panic); @@ -311,15 +312,18 @@ void panic(const char *fmt, ...) * stop themself or will wait until they are stopped by the 1st CPU * with smp_send_stop(). * - * `old_cpu == PANIC_CPU_INVALID' means this is the 1st CPU which - * comes here, so go ahead. + * cmpxchg success means this is the 1st CPU which comes here, + * so go ahead. * `old_cpu == this_cpu' means we came from nmi_panic() which sets * panic_cpu to this CPU. In this case, this is also the 1st CPU. */ + old_cpu = PANIC_CPU_INVALID; this_cpu = raw_smp_processor_id(); - old_cpu = atomic_cmpxchg(&panic_cpu, PANIC_CPU_INVALID, this_cpu); - if (old_cpu != PANIC_CPU_INVALID && old_cpu != this_cpu) + /* atomic_try_cmpxchg updates old_cpu on failure */ + if (atomic_try_cmpxchg(&panic_cpu, &old_cpu, this_cpu)) { + /* go ahead */ + } else if (old_cpu != this_cpu) panic_smp_self_stop(); console_verbose(); diff --git a/kernel/pid_namespace.c b/kernel/pid_namespace.c index 619972c787..3028b2218a 100644 --- a/kernel/pid_namespace.c +++ b/kernel/pid_namespace.c @@ -286,12 +286,6 @@ static int pid_ns_ctl_handler(struct ctl_table *table, int write, if (write && !checkpoint_restore_ns_capable(pid_ns->user_ns)) return -EPERM; - /* - * Writing directly to ns' last_pid field is OK, since this field - * is volatile in a living namespace anyway and a code writing to - * it should synchronize its usage with external means. - */ - next = idr_get_cursor(&pid_ns->idr) - 1; tmp.data = &next; diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c index 8d35b9f9aa..dee341ae4a 100644 --- a/kernel/power/hibernate.c +++ b/kernel/power/hibernate.c @@ -684,7 +684,7 @@ static void power_down(void) cpu_relax(); } -static int load_image_and_restore(bool snapshot_test) +static int load_image_and_restore(void) { int error; unsigned int flags; @@ -694,12 +694,12 @@ static int load_image_and_restore(bool snapshot_test) lock_device_hotplug(); error = create_basic_memory_bitmaps(); if (error) { - swsusp_close(snapshot_test); + swsusp_close(); goto Unlock; } error = swsusp_read(&flags); - swsusp_close(snapshot_test); + swsusp_close(); if (!error) error = hibernation_restore(flags & SF_PLATFORM_MODE); @@ -788,7 +788,7 @@ int hibernate(void) pm_pr_dbg("Checking hibernation image\n"); error = swsusp_check(false); if (!error) - error = load_image_and_restore(false); + error = load_image_and_restore(); } thaw_processes(); @@ -952,7 +952,7 @@ static int software_resume(void) /* The snapshot device should not be opened while we're running */ if (!hibernate_acquire()) { error = -EBUSY; - swsusp_close(true); + swsusp_close(); goto Unlock; } @@ -973,7 +973,7 @@ static int software_resume(void) goto Close_Finish; } - error = load_image_and_restore(true); + error = load_image_and_restore(); thaw_processes(); Finish: pm_notifier_call_chain(PM_POST_RESTORE); @@ -987,7 +987,7 @@ static int software_resume(void) pm_pr_dbg("Hibernation image not present or could not be loaded.\n"); return error; Close_Finish: - swsusp_close(true); + swsusp_close(); goto Finish; } diff --git a/kernel/power/power.h b/kernel/power/power.h index a98f95e309..17fd9aaaf0 100644 --- a/kernel/power/power.h +++ b/kernel/power/power.h @@ -172,7 +172,7 @@ int swsusp_check(bool exclusive); extern void swsusp_free(void); extern int swsusp_read(unsigned int *flags_p); extern int swsusp_write(unsigned int flags); -void swsusp_close(bool exclusive); +void swsusp_close(void); #ifdef CONFIG_SUSPEND extern int swsusp_unmark(void); #endif diff --git a/kernel/power/swap.c b/kernel/power/swap.c index d71c590550..d44f5937f1 100644 --- a/kernel/power/swap.c +++ b/kernel/power/swap.c @@ -222,7 +222,7 @@ int swsusp_swap_in_use(void) */ static unsigned short root_swap = 0xffff; -static struct block_device *hib_resume_bdev; +static struct bdev_handle *hib_resume_bdev_handle; struct hib_bio_batch { atomic_t count; @@ -276,7 +276,8 @@ static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr, struct bio *bio; int error = 0; - bio = bio_alloc(hib_resume_bdev, 1, opf, GFP_NOIO | __GFP_HIGH); + bio = bio_alloc(hib_resume_bdev_handle->bdev, 1, opf, + GFP_NOIO | __GFP_HIGH); bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9); if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) { @@ -356,14 +357,14 @@ static int swsusp_swap_check(void) return res; root_swap = res; - hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, + hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device, BLK_OPEN_WRITE, NULL, NULL); - if (IS_ERR(hib_resume_bdev)) - return PTR_ERR(hib_resume_bdev); + if (IS_ERR(hib_resume_bdev_handle)) + return PTR_ERR(hib_resume_bdev_handle); - res = set_blocksize(hib_resume_bdev, PAGE_SIZE); + res = set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE); if (res < 0) - blkdev_put(hib_resume_bdev, NULL); + bdev_release(hib_resume_bdev_handle); return res; } @@ -443,7 +444,7 @@ static int get_swap_writer(struct swap_map_handle *handle) err_rel: release_swap_writer(handle); err_close: - swsusp_close(false); + swsusp_close(); return ret; } @@ -508,7 +509,7 @@ static int swap_writer_finish(struct swap_map_handle *handle, if (error) free_all_swap_pages(root_swap); release_swap_writer(handle); - swsusp_close(false); + swsusp_close(); return error; } @@ -1513,7 +1514,7 @@ end: static void *swsusp_holder; /** - * swsusp_check - Check for swsusp signature in the resume device + * swsusp_check - Open the resume device and check for the swsusp signature. * @exclusive: Open the resume device exclusively. */ @@ -1522,10 +1523,10 @@ int swsusp_check(bool exclusive) void *holder = exclusive ? &swsusp_holder : NULL; int error; - hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, BLK_OPEN_READ, - holder, NULL); - if (!IS_ERR(hib_resume_bdev)) { - set_blocksize(hib_resume_bdev, PAGE_SIZE); + hib_resume_bdev_handle = bdev_open_by_dev(swsusp_resume_device, + BLK_OPEN_READ, holder, NULL); + if (!IS_ERR(hib_resume_bdev_handle)) { + set_blocksize(hib_resume_bdev_handle->bdev, PAGE_SIZE); clear_page(swsusp_header); error = hib_submit_io(REQ_OP_READ, swsusp_resume_block, swsusp_header, NULL); @@ -1550,11 +1551,11 @@ int swsusp_check(bool exclusive) put: if (error) - blkdev_put(hib_resume_bdev, holder); + bdev_release(hib_resume_bdev_handle); else pr_debug("Image signature found, resuming\n"); } else { - error = PTR_ERR(hib_resume_bdev); + error = PTR_ERR(hib_resume_bdev_handle); } if (error) @@ -1564,18 +1565,18 @@ put: } /** - * swsusp_close - close swap device. + * swsusp_close - close resume device. * @exclusive: Close the resume device which is exclusively opened. */ -void swsusp_close(bool exclusive) +void swsusp_close(void) { - if (IS_ERR(hib_resume_bdev)) { + if (IS_ERR(hib_resume_bdev_handle)) { pr_debug("Image device not initialised\n"); return; } - blkdev_put(hib_resume_bdev, exclusive ? &swsusp_holder : NULL); + bdev_release(hib_resume_bdev_handle); } /** diff --git a/kernel/printk/Makefile b/kernel/printk/Makefile index f5b388e810..39a2b61c72 100644 --- a/kernel/printk/Makefile +++ b/kernel/printk/Makefile @@ -1,6 +1,6 @@ # SPDX-License-Identifier: GPL-2.0-only obj-y = printk.o -obj-$(CONFIG_PRINTK) += printk_safe.o +obj-$(CONFIG_PRINTK) += printk_safe.o nbcon.o obj-$(CONFIG_A11Y_BRAILLE_CONSOLE) += braille.o obj-$(CONFIG_PRINTK_INDEX) += index.o diff --git a/kernel/printk/internal.h b/kernel/printk/internal.h index 7d4979d5c3..6c2afee5ef 100644 --- a/kernel/printk/internal.h +++ b/kernel/printk/internal.h @@ -3,6 +3,8 @@ * internal.h - printk internal definitions */ #include <linux/percpu.h> +#include <linux/console.h> +#include "printk_ringbuffer.h" #if defined(CONFIG_PRINTK) && defined(CONFIG_SYSCTL) void __init printk_sysctl_init(void); @@ -12,6 +14,12 @@ int devkmsg_sysctl_set_loglvl(struct ctl_table *table, int write, #define printk_sysctl_init() do { } while (0) #endif +#define con_printk(lvl, con, fmt, ...) \ + printk(lvl pr_fmt("%s%sconsole [%s%d] " fmt), \ + (con->flags & CON_NBCON) ? "" : "legacy ", \ + (con->flags & CON_BOOT) ? "boot" : "", \ + con->name, con->index, ##__VA_ARGS__) + #ifdef CONFIG_PRINTK #ifdef CONFIG_PRINTK_CALLER @@ -35,6 +43,8 @@ enum printk_info_flags { LOG_CONT = 8, /* text is a fragment of a continuation line */ }; +extern struct printk_ringbuffer *prb; + __printf(4, 0) int vprintk_store(int facility, int level, const struct dev_printk_info *dev_info, @@ -61,6 +71,13 @@ void defer_console_output(void); u16 printk_parse_prefix(const char *text, int *level, enum printk_info_flags *flags); + +u64 nbcon_seq_read(struct console *con); +void nbcon_seq_force(struct console *con, u64 seq); +bool nbcon_alloc(struct console *con); +void nbcon_init(struct console *con); +void nbcon_free(struct console *con); + #else #define PRINTK_PREFIX_MAX 0 @@ -76,8 +93,16 @@ u16 printk_parse_prefix(const char *text, int *level, #define printk_safe_exit_irqrestore(flags) local_irq_restore(flags) static inline bool printk_percpu_data_ready(void) { return false; } +static inline u64 nbcon_seq_read(struct console *con) { return 0; } +static inline void nbcon_seq_force(struct console *con, u64 seq) { } +static inline bool nbcon_alloc(struct console *con) { return false; } +static inline void nbcon_init(struct console *con) { } +static inline void nbcon_free(struct console *con) { } + #endif /* CONFIG_PRINTK */ +extern struct printk_buffers printk_shared_pbufs; + /** * struct printk_buffers - Buffers to read/format/output printk messages. * @outbuf: After formatting, contains text to output. @@ -105,3 +130,9 @@ struct printk_message { }; bool other_cpu_in_panic(void); +bool printk_get_next_message(struct printk_message *pmsg, u64 seq, + bool is_extended, bool may_supress); + +#ifdef CONFIG_PRINTK +void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped); +#endif diff --git a/kernel/printk/nbcon.c b/kernel/printk/nbcon.c new file mode 100644 index 0000000000..b96077152f --- /dev/null +++ b/kernel/printk/nbcon.c @@ -0,0 +1,1029 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2022 Linutronix GmbH, John Ogness +// Copyright (C) 2022 Intel, Thomas Gleixner + +#include <linux/kernel.h> +#include <linux/console.h> +#include <linux/delay.h> +#include <linux/slab.h> +#include "internal.h" +/* + * Printk console printing implementation for consoles which does not depend + * on the legacy style console_lock mechanism. + * + * The state of the console is maintained in the "nbcon_state" atomic + * variable. + * + * The console is locked when: + * + * - The 'prio' field contains the priority of the context that owns the + * console. Only higher priority contexts are allowed to take over the + * lock. A value of 0 (NBCON_PRIO_NONE) means the console is not locked. + * + * - The 'cpu' field denotes on which CPU the console is locked. It is used + * to prevent busy waiting on the same CPU. Also it informs the lock owner + * that it has lost the lock in a more complex scenario when the lock was + * taken over by a higher priority context, released, and taken on another + * CPU with the same priority as the interrupted owner. + * + * The acquire mechanism uses a few more fields: + * + * - The 'req_prio' field is used by the handover approach to make the + * current owner aware that there is a context with a higher priority + * waiting for the friendly handover. + * + * - The 'unsafe' field allows to take over the console in a safe way in the + * middle of emitting a message. The field is set only when accessing some + * shared resources or when the console device is manipulated. It can be + * cleared, for example, after emitting one character when the console + * device is in a consistent state. + * + * - The 'unsafe_takeover' field is set when a hostile takeover took the + * console in an unsafe state. The console will stay in the unsafe state + * until re-initialized. + * + * The acquire mechanism uses three approaches: + * + * 1) Direct acquire when the console is not owned or is owned by a lower + * priority context and is in a safe state. + * + * 2) Friendly handover mechanism uses a request/grant handshake. It is used + * when the current owner has lower priority and the console is in an + * unsafe state. + * + * The requesting context: + * + * a) Sets its priority into the 'req_prio' field. + * + * b) Waits (with a timeout) for the owning context to unlock the + * console. + * + * c) Takes the lock and clears the 'req_prio' field. + * + * The owning context: + * + * a) Observes the 'req_prio' field set on exit from the unsafe + * console state. + * + * b) Gives up console ownership by clearing the 'prio' field. + * + * 3) Unsafe hostile takeover allows to take over the lock even when the + * console is an unsafe state. It is used only in panic() by the final + * attempt to flush consoles in a try and hope mode. + * + * Note that separate record buffers are used in panic(). As a result, + * the messages can be read and formatted without any risk even after + * using the hostile takeover in unsafe state. + * + * The release function simply clears the 'prio' field. + * + * All operations on @console::nbcon_state are atomic cmpxchg based to + * handle concurrency. + * + * The acquire/release functions implement only minimal policies: + * + * - Preference for higher priority contexts. + * - Protection of the panic CPU. + * + * All other policy decisions must be made at the call sites: + * + * - What is marked as an unsafe section. + * - Whether to spin-wait if there is already an owner and the console is + * in an unsafe state. + * - Whether to attempt an unsafe hostile takeover. + * + * The design allows to implement the well known: + * + * acquire() + * output_one_printk_record() + * release() + * + * The output of one printk record might be interrupted with a higher priority + * context. The new owner is supposed to reprint the entire interrupted record + * from scratch. + */ + +/** + * nbcon_state_set - Helper function to set the console state + * @con: Console to update + * @new: The new state to write + * + * Only to be used when the console is not yet or no longer visible in the + * system. Otherwise use nbcon_state_try_cmpxchg(). + */ +static inline void nbcon_state_set(struct console *con, struct nbcon_state *new) +{ + atomic_set(&ACCESS_PRIVATE(con, nbcon_state), new->atom); +} + +/** + * nbcon_state_read - Helper function to read the console state + * @con: Console to read + * @state: The state to store the result + */ +static inline void nbcon_state_read(struct console *con, struct nbcon_state *state) +{ + state->atom = atomic_read(&ACCESS_PRIVATE(con, nbcon_state)); +} + +/** + * nbcon_state_try_cmpxchg() - Helper function for atomic_try_cmpxchg() on console state + * @con: Console to update + * @cur: Old/expected state + * @new: New state + * + * Return: True on success. False on fail and @cur is updated. + */ +static inline bool nbcon_state_try_cmpxchg(struct console *con, struct nbcon_state *cur, + struct nbcon_state *new) +{ + return atomic_try_cmpxchg(&ACCESS_PRIVATE(con, nbcon_state), &cur->atom, new->atom); +} + +#ifdef CONFIG_64BIT + +#define __seq_to_nbcon_seq(seq) (seq) +#define __nbcon_seq_to_seq(seq) (seq) + +#else /* CONFIG_64BIT */ + +#define __seq_to_nbcon_seq(seq) ((u32)seq) + +static inline u64 __nbcon_seq_to_seq(u32 nbcon_seq) +{ + u64 seq; + u64 rb_next_seq; + + /* + * The provided sequence is only the lower 32 bits of the ringbuffer + * sequence. It needs to be expanded to 64bit. Get the next sequence + * number from the ringbuffer and fold it. + * + * Having a 32bit representation in the console is sufficient. + * If a console ever gets more than 2^31 records behind + * the ringbuffer then this is the least of the problems. + * + * Also the access to the ring buffer is always safe. + */ + rb_next_seq = prb_next_seq(prb); + seq = rb_next_seq - ((u32)rb_next_seq - nbcon_seq); + + return seq; +} + +#endif /* CONFIG_64BIT */ + +/** + * nbcon_seq_read - Read the current console sequence + * @con: Console to read the sequence of + * + * Return: Sequence number of the next record to print on @con. + */ +u64 nbcon_seq_read(struct console *con) +{ + unsigned long nbcon_seq = atomic_long_read(&ACCESS_PRIVATE(con, nbcon_seq)); + + return __nbcon_seq_to_seq(nbcon_seq); +} + +/** + * nbcon_seq_force - Force console sequence to a specific value + * @con: Console to work on + * @seq: Sequence number value to set + * + * Only to be used during init (before registration) or in extreme situations + * (such as panic with CONSOLE_REPLAY_ALL). + */ +void nbcon_seq_force(struct console *con, u64 seq) +{ + /* + * If the specified record no longer exists, the oldest available record + * is chosen. This is especially important on 32bit systems because only + * the lower 32 bits of the sequence number are stored. The upper 32 bits + * are derived from the sequence numbers available in the ringbuffer. + */ + u64 valid_seq = max_t(u64, seq, prb_first_valid_seq(prb)); + + atomic_long_set(&ACCESS_PRIVATE(con, nbcon_seq), __seq_to_nbcon_seq(valid_seq)); + + /* Clear con->seq since nbcon consoles use con->nbcon_seq instead. */ + con->seq = 0; +} + +/** + * nbcon_seq_try_update - Try to update the console sequence number + * @ctxt: Pointer to an acquire context that contains + * all information about the acquire mode + * @new_seq: The new sequence number to set + * + * @ctxt->seq is updated to the new value of @con::nbcon_seq (expanded to + * the 64bit value). This could be a different value than @new_seq if + * nbcon_seq_force() was used or the current context no longer owns the + * console. In the later case, it will stop printing anyway. + */ +static void nbcon_seq_try_update(struct nbcon_context *ctxt, u64 new_seq) +{ + unsigned long nbcon_seq = __seq_to_nbcon_seq(ctxt->seq); + struct console *con = ctxt->console; + + if (atomic_long_try_cmpxchg(&ACCESS_PRIVATE(con, nbcon_seq), &nbcon_seq, + __seq_to_nbcon_seq(new_seq))) { + ctxt->seq = new_seq; + } else { + ctxt->seq = nbcon_seq_read(con); + } +} + +/** + * nbcon_context_try_acquire_direct - Try to acquire directly + * @ctxt: The context of the caller + * @cur: The current console state + * + * Acquire the console when it is released. Also acquire the console when + * the current owner has a lower priority and the console is in a safe state. + * + * Return: 0 on success. Otherwise, an error code on failure. Also @cur + * is updated to the latest state when failed to modify it. + * + * Errors: + * + * -EPERM: A panic is in progress and this is not the panic CPU. + * Or the current owner or waiter has the same or higher + * priority. No acquire method can be successful in + * this case. + * + * -EBUSY: The current owner has a lower priority but the console + * in an unsafe state. The caller should try using + * the handover acquire method. + */ +static int nbcon_context_try_acquire_direct(struct nbcon_context *ctxt, + struct nbcon_state *cur) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state new; + + do { + if (other_cpu_in_panic()) + return -EPERM; + + if (ctxt->prio <= cur->prio || ctxt->prio <= cur->req_prio) + return -EPERM; + + if (cur->unsafe) + return -EBUSY; + + /* + * The console should never be safe for a direct acquire + * if an unsafe hostile takeover has ever happened. + */ + WARN_ON_ONCE(cur->unsafe_takeover); + + new.atom = cur->atom; + new.prio = ctxt->prio; + new.req_prio = NBCON_PRIO_NONE; + new.unsafe = cur->unsafe_takeover; + new.cpu = cpu; + + } while (!nbcon_state_try_cmpxchg(con, cur, &new)); + + return 0; +} + +static bool nbcon_waiter_matches(struct nbcon_state *cur, int expected_prio) +{ + /* + * The request context is well defined by the @req_prio because: + * + * - Only a context with a higher priority can take over the request. + * - There are only three priorities. + * - Only one CPU is allowed to request PANIC priority. + * - Lower priorities are ignored during panic() until reboot. + * + * As a result, the following scenario is *not* possible: + * + * 1. Another context with a higher priority directly takes ownership. + * 2. The higher priority context releases the ownership. + * 3. A lower priority context takes the ownership. + * 4. Another context with the same priority as this context + * creates a request and starts waiting. + */ + + return (cur->req_prio == expected_prio); +} + +/** + * nbcon_context_try_acquire_requested - Try to acquire after having + * requested a handover + * @ctxt: The context of the caller + * @cur: The current console state + * + * This is a helper function for nbcon_context_try_acquire_handover(). + * It is called when the console is in an unsafe state. The current + * owner will release the console on exit from the unsafe region. + * + * Return: 0 on success and @cur is updated to the new console state. + * Otherwise an error code on failure. + * + * Errors: + * + * -EPERM: A panic is in progress and this is not the panic CPU + * or this context is no longer the waiter. + * + * -EBUSY: The console is still locked. The caller should + * continue waiting. + * + * Note: The caller must still remove the request when an error has occurred + * except when this context is no longer the waiter. + */ +static int nbcon_context_try_acquire_requested(struct nbcon_context *ctxt, + struct nbcon_state *cur) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state new; + + /* Note that the caller must still remove the request! */ + if (other_cpu_in_panic()) + return -EPERM; + + /* + * Note that the waiter will also change if there was an unsafe + * hostile takeover. + */ + if (!nbcon_waiter_matches(cur, ctxt->prio)) + return -EPERM; + + /* If still locked, caller should continue waiting. */ + if (cur->prio != NBCON_PRIO_NONE) + return -EBUSY; + + /* + * The previous owner should have never released ownership + * in an unsafe region. + */ + WARN_ON_ONCE(cur->unsafe); + + new.atom = cur->atom; + new.prio = ctxt->prio; + new.req_prio = NBCON_PRIO_NONE; + new.unsafe = cur->unsafe_takeover; + new.cpu = cpu; + + if (!nbcon_state_try_cmpxchg(con, cur, &new)) { + /* + * The acquire could fail only when it has been taken + * over by a higher priority context. + */ + WARN_ON_ONCE(nbcon_waiter_matches(cur, ctxt->prio)); + return -EPERM; + } + + /* Handover success. This context now owns the console. */ + return 0; +} + +/** + * nbcon_context_try_acquire_handover - Try to acquire via handover + * @ctxt: The context of the caller + * @cur: The current console state + * + * The function must be called only when the context has higher priority + * than the current owner and the console is in an unsafe state. + * It is the case when nbcon_context_try_acquire_direct() returns -EBUSY. + * + * The function sets "req_prio" field to make the current owner aware of + * the request. Then it waits until the current owner releases the console, + * or an even higher context takes over the request, or timeout expires. + * + * The current owner checks the "req_prio" field on exit from the unsafe + * region and releases the console. It does not touch the "req_prio" field + * so that the console stays reserved for the waiter. + * + * Return: 0 on success. Otherwise, an error code on failure. Also @cur + * is updated to the latest state when failed to modify it. + * + * Errors: + * + * -EPERM: A panic is in progress and this is not the panic CPU. + * Or a higher priority context has taken over the + * console or the handover request. + * + * -EBUSY: The current owner is on the same CPU so that the hand + * shake could not work. Or the current owner is not + * willing to wait (zero timeout). Or the console does + * not enter the safe state before timeout passed. The + * caller might still use the unsafe hostile takeover + * when allowed. + * + * -EAGAIN: @cur has changed when creating the handover request. + * The caller should retry with direct acquire. + */ +static int nbcon_context_try_acquire_handover(struct nbcon_context *ctxt, + struct nbcon_state *cur) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state new; + int timeout; + int request_err = -EBUSY; + + /* + * Check that the handover is called when the direct acquire failed + * with -EBUSY. + */ + WARN_ON_ONCE(ctxt->prio <= cur->prio || ctxt->prio <= cur->req_prio); + WARN_ON_ONCE(!cur->unsafe); + + /* Handover is not possible on the same CPU. */ + if (cur->cpu == cpu) + return -EBUSY; + + /* + * Console stays unsafe after an unsafe takeover until re-initialized. + * Waiting is not going to help in this case. + */ + if (cur->unsafe_takeover) + return -EBUSY; + + /* Is the caller willing to wait? */ + if (ctxt->spinwait_max_us == 0) + return -EBUSY; + + /* + * Setup a request for the handover. The caller should try to acquire + * the console directly when the current state has been modified. + */ + new.atom = cur->atom; + new.req_prio = ctxt->prio; + if (!nbcon_state_try_cmpxchg(con, cur, &new)) + return -EAGAIN; + + cur->atom = new.atom; + + /* Wait until there is no owner and then acquire the console. */ + for (timeout = ctxt->spinwait_max_us; timeout >= 0; timeout--) { + /* On successful acquire, this request is cleared. */ + request_err = nbcon_context_try_acquire_requested(ctxt, cur); + if (!request_err) + return 0; + + /* + * If the acquire should be aborted, it must be ensured + * that the request is removed before returning to caller. + */ + if (request_err == -EPERM) + break; + + udelay(1); + + /* Re-read the state because some time has passed. */ + nbcon_state_read(con, cur); + } + + /* Timed out or aborted. Carefully remove handover request. */ + do { + /* + * No need to remove request if there is a new waiter. This + * can only happen if a higher priority context has taken over + * the console or the handover request. + */ + if (!nbcon_waiter_matches(cur, ctxt->prio)) + return -EPERM; + + /* Unset request for handover. */ + new.atom = cur->atom; + new.req_prio = NBCON_PRIO_NONE; + if (nbcon_state_try_cmpxchg(con, cur, &new)) { + /* + * Request successfully unset. Report failure of + * acquiring via handover. + */ + cur->atom = new.atom; + return request_err; + } + + /* + * Unable to remove request. Try to acquire in case + * the owner has released the lock. + */ + } while (nbcon_context_try_acquire_requested(ctxt, cur)); + + /* Lucky timing. The acquire succeeded while removing the request. */ + return 0; +} + +/** + * nbcon_context_try_acquire_hostile - Acquire via unsafe hostile takeover + * @ctxt: The context of the caller + * @cur: The current console state + * + * Acquire the console even in the unsafe state. + * + * It can be permitted by setting the 'allow_unsafe_takeover' field only + * by the final attempt to flush messages in panic(). + * + * Return: 0 on success. -EPERM when not allowed by the context. + */ +static int nbcon_context_try_acquire_hostile(struct nbcon_context *ctxt, + struct nbcon_state *cur) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state new; + + if (!ctxt->allow_unsafe_takeover) + return -EPERM; + + /* Ensure caller is allowed to perform unsafe hostile takeovers. */ + if (WARN_ON_ONCE(ctxt->prio != NBCON_PRIO_PANIC)) + return -EPERM; + + /* + * Check that try_acquire_direct() and try_acquire_handover() returned + * -EBUSY in the right situation. + */ + WARN_ON_ONCE(ctxt->prio <= cur->prio || ctxt->prio <= cur->req_prio); + WARN_ON_ONCE(cur->unsafe != true); + + do { + new.atom = cur->atom; + new.cpu = cpu; + new.prio = ctxt->prio; + new.unsafe |= cur->unsafe_takeover; + new.unsafe_takeover |= cur->unsafe; + + } while (!nbcon_state_try_cmpxchg(con, cur, &new)); + + return 0; +} + +static struct printk_buffers panic_nbcon_pbufs; + +/** + * nbcon_context_try_acquire - Try to acquire nbcon console + * @ctxt: The context of the caller + * + * Return: True if the console was acquired. False otherwise. + * + * If the caller allowed an unsafe hostile takeover, on success the + * caller should check the current console state to see if it is + * in an unsafe state. Otherwise, on success the caller may assume + * the console is not in an unsafe state. + */ +__maybe_unused +static bool nbcon_context_try_acquire(struct nbcon_context *ctxt) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state cur; + int err; + + nbcon_state_read(con, &cur); +try_again: + err = nbcon_context_try_acquire_direct(ctxt, &cur); + if (err != -EBUSY) + goto out; + + err = nbcon_context_try_acquire_handover(ctxt, &cur); + if (err == -EAGAIN) + goto try_again; + if (err != -EBUSY) + goto out; + + err = nbcon_context_try_acquire_hostile(ctxt, &cur); +out: + if (err) + return false; + + /* Acquire succeeded. */ + + /* Assign the appropriate buffer for this context. */ + if (atomic_read(&panic_cpu) == cpu) + ctxt->pbufs = &panic_nbcon_pbufs; + else + ctxt->pbufs = con->pbufs; + + /* Set the record sequence for this context to print. */ + ctxt->seq = nbcon_seq_read(ctxt->console); + + return true; +} + +static bool nbcon_owner_matches(struct nbcon_state *cur, int expected_cpu, + int expected_prio) +{ + /* + * Since consoles can only be acquired by higher priorities, + * owning contexts are uniquely identified by @prio. However, + * since contexts can unexpectedly lose ownership, it is + * possible that later another owner appears with the same + * priority. For this reason @cpu is also needed. + */ + + if (cur->prio != expected_prio) + return false; + + if (cur->cpu != expected_cpu) + return false; + + return true; +} + +/** + * nbcon_context_release - Release the console + * @ctxt: The nbcon context from nbcon_context_try_acquire() + */ +static void nbcon_context_release(struct nbcon_context *ctxt) +{ + unsigned int cpu = smp_processor_id(); + struct console *con = ctxt->console; + struct nbcon_state cur; + struct nbcon_state new; + + nbcon_state_read(con, &cur); + + do { + if (!nbcon_owner_matches(&cur, cpu, ctxt->prio)) + break; + + new.atom = cur.atom; + new.prio = NBCON_PRIO_NONE; + + /* + * If @unsafe_takeover is set, it is kept set so that + * the state remains permanently unsafe. + */ + new.unsafe |= cur.unsafe_takeover; + + } while (!nbcon_state_try_cmpxchg(con, &cur, &new)); + + ctxt->pbufs = NULL; +} + +/** + * nbcon_context_can_proceed - Check whether ownership can proceed + * @ctxt: The nbcon context from nbcon_context_try_acquire() + * @cur: The current console state + * + * Return: True if this context still owns the console. False if + * ownership was handed over or taken. + * + * Must be invoked when entering the unsafe state to make sure that it still + * owns the lock. Also must be invoked when exiting the unsafe context + * to eventually free the lock for a higher priority context which asked + * for the friendly handover. + * + * It can be called inside an unsafe section when the console is just + * temporary in safe state instead of exiting and entering the unsafe + * state. + * + * Also it can be called in the safe context before doing an expensive + * safe operation. It does not make sense to do the operation when + * a higher priority context took the lock. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. + */ +static bool nbcon_context_can_proceed(struct nbcon_context *ctxt, struct nbcon_state *cur) +{ + unsigned int cpu = smp_processor_id(); + + /* Make sure this context still owns the console. */ + if (!nbcon_owner_matches(cur, cpu, ctxt->prio)) + return false; + + /* The console owner can proceed if there is no waiter. */ + if (cur->req_prio == NBCON_PRIO_NONE) + return true; + + /* + * A console owner within an unsafe region is always allowed to + * proceed, even if there are waiters. It can perform a handover + * when exiting the unsafe region. Otherwise the waiter will + * need to perform an unsafe hostile takeover. + */ + if (cur->unsafe) + return true; + + /* Waiters always have higher priorities than owners. */ + WARN_ON_ONCE(cur->req_prio <= cur->prio); + + /* + * Having a safe point for take over and eventually a few + * duplicated characters or a full line is way better than a + * hostile takeover. Post processing can take care of the garbage. + * Release and hand over. + */ + nbcon_context_release(ctxt); + + /* + * It is not clear whether the waiter really took over ownership. The + * outermost callsite must make the final decision whether console + * ownership is needed for it to proceed. If yes, it must reacquire + * ownership (possibly hostile) before carefully proceeding. + * + * The calling context no longer owns the console so go back all the + * way instead of trying to implement reacquire heuristics in tons of + * places. + */ + return false; +} + +/** + * nbcon_can_proceed - Check whether ownership can proceed + * @wctxt: The write context that was handed to the write function + * + * Return: True if this context still owns the console. False if + * ownership was handed over or taken. + * + * It is used in nbcon_enter_unsafe() to make sure that it still owns the + * lock. Also it is used in nbcon_exit_unsafe() to eventually free the lock + * for a higher priority context which asked for the friendly handover. + * + * It can be called inside an unsafe section when the console is just + * temporary in safe state instead of exiting and entering the unsafe state. + * + * Also it can be called in the safe context before doing an expensive safe + * operation. It does not make sense to do the operation when a higher + * priority context took the lock. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. + */ +bool nbcon_can_proceed(struct nbcon_write_context *wctxt) +{ + struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); + struct console *con = ctxt->console; + struct nbcon_state cur; + + nbcon_state_read(con, &cur); + + return nbcon_context_can_proceed(ctxt, &cur); +} +EXPORT_SYMBOL_GPL(nbcon_can_proceed); + +#define nbcon_context_enter_unsafe(c) __nbcon_context_update_unsafe(c, true) +#define nbcon_context_exit_unsafe(c) __nbcon_context_update_unsafe(c, false) + +/** + * __nbcon_context_update_unsafe - Update the unsafe bit in @con->nbcon_state + * @ctxt: The nbcon context from nbcon_context_try_acquire() + * @unsafe: The new value for the unsafe bit + * + * Return: True if the unsafe state was updated and this context still + * owns the console. Otherwise false if ownership was handed + * over or taken. + * + * This function allows console owners to modify the unsafe status of the + * console. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. + * + * Internal helper to avoid duplicated code. + */ +static bool __nbcon_context_update_unsafe(struct nbcon_context *ctxt, bool unsafe) +{ + struct console *con = ctxt->console; + struct nbcon_state cur; + struct nbcon_state new; + + nbcon_state_read(con, &cur); + + do { + /* + * The unsafe bit must not be cleared if an + * unsafe hostile takeover has occurred. + */ + if (!unsafe && cur.unsafe_takeover) + goto out; + + if (!nbcon_context_can_proceed(ctxt, &cur)) + return false; + + new.atom = cur.atom; + new.unsafe = unsafe; + } while (!nbcon_state_try_cmpxchg(con, &cur, &new)); + + cur.atom = new.atom; +out: + return nbcon_context_can_proceed(ctxt, &cur); +} + +/** + * nbcon_enter_unsafe - Enter an unsafe region in the driver + * @wctxt: The write context that was handed to the write function + * + * Return: True if this context still owns the console. False if + * ownership was handed over or taken. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. + */ +bool nbcon_enter_unsafe(struct nbcon_write_context *wctxt) +{ + struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); + + return nbcon_context_enter_unsafe(ctxt); +} +EXPORT_SYMBOL_GPL(nbcon_enter_unsafe); + +/** + * nbcon_exit_unsafe - Exit an unsafe region in the driver + * @wctxt: The write context that was handed to the write function + * + * Return: True if this context still owns the console. False if + * ownership was handed over or taken. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. + */ +bool nbcon_exit_unsafe(struct nbcon_write_context *wctxt) +{ + struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); + + return nbcon_context_exit_unsafe(ctxt); +} +EXPORT_SYMBOL_GPL(nbcon_exit_unsafe); + +/** + * nbcon_emit_next_record - Emit a record in the acquired context + * @wctxt: The write context that will be handed to the write function + * + * Return: True if this context still owns the console. False if + * ownership was handed over or taken. + * + * When this function returns false then the calling context no longer owns + * the console and is no longer allowed to go forward. In this case it must + * back out immediately and carefully. The buffer content is also no longer + * trusted since it no longer belongs to the calling context. If the caller + * wants to do more it must reacquire the console first. + * + * When true is returned, @wctxt->ctxt.backlog indicates whether there are + * still records pending in the ringbuffer, + */ +__maybe_unused +static bool nbcon_emit_next_record(struct nbcon_write_context *wctxt) +{ + struct nbcon_context *ctxt = &ACCESS_PRIVATE(wctxt, ctxt); + struct console *con = ctxt->console; + bool is_extended = console_srcu_read_flags(con) & CON_EXTENDED; + struct printk_message pmsg = { + .pbufs = ctxt->pbufs, + }; + unsigned long con_dropped; + struct nbcon_state cur; + unsigned long dropped; + bool done; + + /* + * The printk buffers are filled within an unsafe section. This + * prevents NBCON_PRIO_NORMAL and NBCON_PRIO_EMERGENCY from + * clobbering each other. + */ + + if (!nbcon_context_enter_unsafe(ctxt)) + return false; + + ctxt->backlog = printk_get_next_message(&pmsg, ctxt->seq, is_extended, true); + if (!ctxt->backlog) + return nbcon_context_exit_unsafe(ctxt); + + /* + * @con->dropped is not protected in case of an unsafe hostile + * takeover. In that situation the update can be racy so + * annotate it accordingly. + */ + con_dropped = data_race(READ_ONCE(con->dropped)); + + dropped = con_dropped + pmsg.dropped; + if (dropped && !is_extended) + console_prepend_dropped(&pmsg, dropped); + + if (!nbcon_context_exit_unsafe(ctxt)) + return false; + + /* For skipped records just update seq/dropped in @con. */ + if (pmsg.outbuf_len == 0) + goto update_con; + + /* Initialize the write context for driver callbacks. */ + wctxt->outbuf = &pmsg.pbufs->outbuf[0]; + wctxt->len = pmsg.outbuf_len; + nbcon_state_read(con, &cur); + wctxt->unsafe_takeover = cur.unsafe_takeover; + + if (con->write_atomic) { + done = con->write_atomic(con, wctxt); + } else { + nbcon_context_release(ctxt); + WARN_ON_ONCE(1); + done = false; + } + + /* If not done, the emit was aborted. */ + if (!done) + return false; + + /* + * Since any dropped message was successfully output, reset the + * dropped count for the console. + */ + dropped = 0; +update_con: + /* + * The dropped count and the sequence number are updated within an + * unsafe section. This limits update races to the panic context and + * allows the panic context to win. + */ + + if (!nbcon_context_enter_unsafe(ctxt)) + return false; + + if (dropped != con_dropped) { + /* Counterpart to the READ_ONCE() above. */ + WRITE_ONCE(con->dropped, dropped); + } + + nbcon_seq_try_update(ctxt, pmsg.seq + 1); + + return nbcon_context_exit_unsafe(ctxt); +} + +/** + * nbcon_alloc - Allocate buffers needed by the nbcon console + * @con: Console to allocate buffers for + * + * Return: True on success. False otherwise and the console cannot + * be used. + * + * This is not part of nbcon_init() because buffer allocation must + * be performed earlier in the console registration process. + */ +bool nbcon_alloc(struct console *con) +{ + if (con->flags & CON_BOOT) { + /* + * Boot console printing is synchronized with legacy console + * printing, so boot consoles can share the same global printk + * buffers. + */ + con->pbufs = &printk_shared_pbufs; + } else { + con->pbufs = kmalloc(sizeof(*con->pbufs), GFP_KERNEL); + if (!con->pbufs) { + con_printk(KERN_ERR, con, "failed to allocate printing buffer\n"); + return false; + } + } + + return true; +} + +/** + * nbcon_init - Initialize the nbcon console specific data + * @con: Console to initialize + * + * nbcon_alloc() *must* be called and succeed before this function + * is called. + * + * This function expects that the legacy @con->seq has been set. + */ +void nbcon_init(struct console *con) +{ + struct nbcon_state state = { }; + + /* nbcon_alloc() must have been called and successful! */ + BUG_ON(!con->pbufs); + + nbcon_seq_force(con, con->seq); + nbcon_state_set(con, &state); +} + +/** + * nbcon_free - Free and cleanup the nbcon console specific data + * @con: Console to free/cleanup nbcon data + */ +void nbcon_free(struct console *con) +{ + struct nbcon_state state = { }; + + nbcon_state_set(con, &state); + + /* Boot consoles share global printk buffers. */ + if (!(con->flags & CON_BOOT)) + kfree(con->pbufs); + + con->pbufs = NULL; +} diff --git a/kernel/printk/printk.c b/kernel/printk/printk.c index 0b3af15297..f2444b581e 100644 --- a/kernel/printk/printk.c +++ b/kernel/printk/printk.c @@ -102,12 +102,6 @@ DEFINE_STATIC_SRCU(console_srcu); */ int __read_mostly suppress_printk; -/* - * During panic, heavy printk by other CPUs can delay the - * panic and risk deadlock on console resources. - */ -static int __read_mostly suppress_panic_printk; - #ifdef CONFIG_LOCKDEP static struct lockdep_map console_lock_dep_map = { .name = "console_lock" @@ -445,6 +439,12 @@ static int console_msg_format = MSG_FORMAT_DEFAULT; static DEFINE_MUTEX(syslog_lock); #ifdef CONFIG_PRINTK +/* + * During panic, heavy printk by other CPUs can delay the + * panic and risk deadlock on console resources. + */ +static int __read_mostly suppress_panic_printk; + DECLARE_WAIT_QUEUE_HEAD(log_wait); /* All 3 protected by @syslog_lock. */ /* the next printk record to read by syslog(READ) or /proc/kmsg */ @@ -494,7 +494,7 @@ _DEFINE_PRINTKRB(printk_rb_static, CONFIG_LOG_BUF_SHIFT - PRB_AVGBITS, static struct printk_ringbuffer printk_rb_dynamic; -static struct printk_ringbuffer *prb = &printk_rb_static; +struct printk_ringbuffer *prb = &printk_rb_static; /* * We cannot access per-CPU data (e.g. per-CPU flush irq_work) before @@ -698,9 +698,6 @@ out: return len; } -static bool printk_get_next_message(struct printk_message *pmsg, u64 seq, - bool is_extended, bool may_supress); - /* /dev/kmsg - userspace message inject/listen interface */ struct devkmsg_user { atomic64_t seq; @@ -1669,7 +1666,6 @@ static int syslog_print_all(char __user *buf, int size, bool clear) prb_rec_init_rd(&r, &info, text, PRINTK_MESSAGE_MAX); - len = 0; prb_for_each_record(seq, prb, seq, &r) { int textlen; @@ -2349,22 +2345,6 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre static u64 syslog_seq; -static size_t record_print_text(const struct printk_record *r, - bool syslog, bool time) -{ - return 0; -} -static ssize_t info_print_ext_header(char *buf, size_t size, - struct printk_info *info) -{ - return 0; -} -static ssize_t msg_print_ext_body(char *buf, size_t size, - char *text, size_t text_len, - struct dev_printk_info *dev_info) { return 0; } -static void console_lock_spinning_enable(void) { } -static int console_lock_spinning_disable_and_check(int cookie) { return 0; } -static bool suppress_message_printing(int level) { return false; } static bool pr_flush(int timeout_ms, bool reset_on_progress) { return true; } static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progress) { return true; } @@ -2404,13 +2384,21 @@ static void set_user_specified(struct console_cmdline *c, bool user_specified) console_set_on_cmdline = 1; } -static int __add_preferred_console(char *name, int idx, char *options, +static int __add_preferred_console(const char *name, const short idx, char *options, char *brl_options, bool user_specified) { struct console_cmdline *c; int i; /* + * We use a signed short index for struct console for device drivers to + * indicate a not yet assigned index or port. However, a negative index + * value is not valid for preferred console. + */ + if (idx < 0) + return -EINVAL; + + /* * See if this tty is not yet registered, and * if we have a slot free. */ @@ -2513,7 +2501,7 @@ __setup("console=", console_setup); * commonly to provide a default console (ie from PROM variables) when * the user has not supplied one. */ -int add_preferred_console(char *name, int idx, char *options) +int add_preferred_console(const char *name, const short idx, char *options) { return __add_preferred_console(name, idx, options, NULL, false); } @@ -2718,6 +2706,8 @@ static void __console_unlock(void) up_console_sem(); } +#ifdef CONFIG_PRINTK + /* * Prepend the message in @pmsg->pbufs->outbuf with a "dropped message". This * is achieved by shifting the existing message over and inserting the dropped @@ -2732,8 +2722,7 @@ static void __console_unlock(void) * * If @pmsg->pbufs->outbuf is modified, @pmsg->outbuf_len is updated. */ -#ifdef CONFIG_PRINTK -static void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped) +void console_prepend_dropped(struct printk_message *pmsg, unsigned long dropped) { struct printk_buffers *pbufs = pmsg->pbufs; const size_t scratchbuf_sz = sizeof(pbufs->scratchbuf); @@ -2764,9 +2753,6 @@ static void console_prepend_dropped(struct printk_message *pmsg, unsigned long d memcpy(outbuf, scratchbuf, len); pmsg->outbuf_len += len; } -#else -#define console_prepend_dropped(pmsg, dropped) -#endif /* CONFIG_PRINTK */ /* * Read and format the specified record (or a later record if the specified @@ -2787,8 +2773,8 @@ static void console_prepend_dropped(struct printk_message *pmsg, unsigned long d * of @pmsg are valid. (See the documentation of struct printk_message * for information about the @pmsg fields.) */ -static bool printk_get_next_message(struct printk_message *pmsg, u64 seq, - bool is_extended, bool may_suppress) +bool printk_get_next_message(struct printk_message *pmsg, u64 seq, + bool is_extended, bool may_suppress) { static int panic_console_dropped; @@ -2847,6 +2833,13 @@ out: } /* + * Used as the printk buffers for non-panic, serialized console printing. + * This is for legacy (!CON_NBCON) as well as all boot (CON_BOOT) consoles. + * Its usage requires the console_lock held. + */ +struct printk_buffers printk_shared_pbufs; + +/* * Print one record for the given console. The record printed is whatever * record is the next available record for the given console. * @@ -2863,12 +2856,10 @@ out: */ static bool console_emit_next_record(struct console *con, bool *handover, int cookie) { - static struct printk_buffers pbufs; - bool is_extended = console_srcu_read_flags(con) & CON_EXTENDED; - char *outbuf = &pbufs.outbuf[0]; + char *outbuf = &printk_shared_pbufs.outbuf[0]; struct printk_message pmsg = { - .pbufs = &pbufs, + .pbufs = &printk_shared_pbufs, }; unsigned long flags; @@ -2919,6 +2910,16 @@ skip: return true; } +#else + +static bool console_emit_next_record(struct console *con, bool *handover, int cookie) +{ + *handover = false; + return false; +} + +#endif /* CONFIG_PRINTK */ + /* * Print out all remaining records to all consoles. * @@ -3163,6 +3164,7 @@ void console_flush_on_panic(enum con_flush_mode mode) if (mode == CONSOLE_REPLAY_ALL) { struct console *c; + short flags; int cookie; u64 seq; @@ -3170,11 +3172,17 @@ void console_flush_on_panic(enum con_flush_mode mode) cookie = console_srcu_read_lock(); for_each_console_srcu(c) { - /* - * This is an unsynchronized assignment, but the - * kernel is in "hope and pray" mode anyway. - */ - c->seq = seq; + flags = console_srcu_read_flags(c); + + if (flags & CON_NBCON) { + nbcon_seq_force(c, seq); + } else { + /* + * This is an unsynchronized assignment. On + * panic legacy consoles are only best effort. + */ + c->seq = seq; + } } console_srcu_read_unlock(cookie); } @@ -3326,11 +3334,6 @@ static void try_enable_default_console(struct console *newcon) newcon->flags |= CON_CONSDEV; } -#define con_printk(lvl, con, fmt, ...) \ - printk(lvl pr_fmt("%sconsole [%s%d] " fmt), \ - (con->flags & CON_BOOT) ? "boot" : "", \ - con->name, con->index, ##__VA_ARGS__) - static void console_init_seq(struct console *newcon, bool bootcon_registered) { struct console *con; @@ -3444,6 +3447,15 @@ void register_console(struct console *newcon) goto unlock; } + if (newcon->flags & CON_NBCON) { + /* + * Ensure the nbcon console buffers can be allocated + * before modifying any global data. + */ + if (!nbcon_alloc(newcon)) + goto unlock; + } + /* * See if we want to enable this console driver by default. * @@ -3471,8 +3483,11 @@ void register_console(struct console *newcon) err = try_enable_preferred_console(newcon, false); /* printk() messages are not printed to the Braille console. */ - if (err || newcon->flags & CON_BRL) + if (err || newcon->flags & CON_BRL) { + if (newcon->flags & CON_NBCON) + nbcon_free(newcon); goto unlock; + } /* * If we have a bootconsole, and are switching to a real console, @@ -3488,6 +3503,9 @@ void register_console(struct console *newcon) newcon->dropped = 0; console_init_seq(newcon, bootcon_registered); + if (newcon->flags & CON_NBCON) + nbcon_init(newcon); + /* * Put this console in the list - keep the * preferred driver at the head of the list. @@ -3579,6 +3597,9 @@ static int unregister_console_locked(struct console *console) */ synchronize_srcu(&console_srcu); + if (console->flags & CON_NBCON) + nbcon_free(console); + console_sysfs_notify(); if (console->exit) @@ -3728,10 +3749,12 @@ late_initcall(printk_late_init); /* If @con is specified, only wait for that console. Otherwise wait for all. */ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progress) { - int remaining = timeout_ms; + unsigned long timeout_jiffies = msecs_to_jiffies(timeout_ms); + unsigned long remaining_jiffies = timeout_jiffies; struct console *c; u64 last_diff = 0; u64 printk_seq; + short flags; int cookie; u64 diff; u64 seq; @@ -3745,6 +3768,9 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre console_unlock(); for (;;) { + unsigned long begin_jiffies; + unsigned long slept_jiffies; + diff = 0; /* @@ -3759,6 +3785,9 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre for_each_console_srcu(c) { if (con && con != c) continue; + + flags = console_srcu_read_flags(c); + /* * If consoles are not usable, it cannot be expected * that they make forward progress, so only increment @@ -3766,31 +3795,33 @@ static bool __pr_flush(struct console *con, int timeout_ms, bool reset_on_progre */ if (!console_is_usable(c)) continue; - printk_seq = c->seq; + + if (flags & CON_NBCON) { + printk_seq = nbcon_seq_read(c); + } else { + printk_seq = c->seq; + } + if (printk_seq < seq) diff += seq - printk_seq; } console_srcu_read_unlock(cookie); if (diff != last_diff && reset_on_progress) - remaining = timeout_ms; + remaining_jiffies = timeout_jiffies; console_unlock(); /* Note: @diff is 0 if there are no usable consoles. */ - if (diff == 0 || remaining == 0) + if (diff == 0 || remaining_jiffies == 0) break; - if (remaining < 0) { - /* no timeout limit */ - msleep(100); - } else if (remaining < 100) { - msleep(remaining); - remaining = 0; - } else { - msleep(100); - remaining -= 100; - } + /* msleep(1) might sleep much longer. Check time by jiffies. */ + begin_jiffies = jiffies; + msleep(1); + slept_jiffies = jiffies - begin_jiffies; + + remaining_jiffies -= min(slept_jiffies, remaining_jiffies); last_diff = diff; } @@ -4194,7 +4225,6 @@ bool kmsg_dump_get_buffer(struct kmsg_dump_iter *iter, bool syslog, prb_rec_init_rd(&r, &info, buf, size); - len = 0; prb_for_each_record(seq, prb, seq, &r) { if (r.info->seq >= iter->next_seq) break; diff --git a/kernel/ptrace.c b/kernel/ptrace.c index 443057bee8..d8b5e13a22 100644 --- a/kernel/ptrace.c +++ b/kernel/ptrace.c @@ -59,7 +59,7 @@ int ptrace_access_vm(struct task_struct *tsk, unsigned long addr, return 0; } - ret = __access_remote_vm(mm, addr, buf, len, gup_flags); + ret = access_remote_vm(mm, addr, buf, len, gup_flags); mmput(mm); return ret; diff --git a/kernel/rcu/Kconfig.debug b/kernel/rcu/Kconfig.debug index 2984de629f..9b0b52e183 100644 --- a/kernel/rcu/Kconfig.debug +++ b/kernel/rcu/Kconfig.debug @@ -105,6 +105,31 @@ config RCU_CPU_STALL_CPUTIME The boot option rcupdate.rcu_cpu_stall_cputime has the same function as this one, but will override this if it exists. +config RCU_CPU_STALL_NOTIFIER + bool "Provide RCU CPU-stall notifiers" + depends on RCU_STALL_COMMON + depends on DEBUG_KERNEL + depends on RCU_EXPERT + default n + help + WARNING: You almost certainly do not want this!!! + + Enable RCU CPU-stall notifiers, which are invoked just before + printing the RCU CPU stall warning. As such, bugs in notifier + callbacks can prevent stall warnings from being printed. + And the whole reason that a stall warning is being printed is + that something is hung up somewhere. Therefore, the notifier + callbacks must be written extremely carefully, preferably + containing only lockless code. After all, it is quite possible + that the whole reason that the RCU CPU stall is happening in + the first place is that someone forgot to release whatever lock + that you are thinking of acquiring. In which case, having your + notifier callback acquire that lock will hang, preventing the + RCU CPU stall warning from appearing. + + Say Y here if you want RCU CPU stall notifiers (you don't want them) + Say N if you are unsure. + config RCU_TRACE bool "Enable tracing for RCU" depends on DEBUG_KERNEL diff --git a/kernel/rcu/rcu.h b/kernel/rcu/rcu.h index 3d1851f82d..f94f65877f 100644 --- a/kernel/rcu/rcu.h +++ b/kernel/rcu/rcu.h @@ -10,6 +10,7 @@ #ifndef __LINUX_RCU_H #define __LINUX_RCU_H +#include <linux/slab.h> #include <trace/events/rcu.h> /* @@ -248,6 +249,12 @@ static inline void debug_rcu_head_unqueue(struct rcu_head *head) } #endif /* #else !CONFIG_DEBUG_OBJECTS_RCU_HEAD */ +static inline void debug_rcu_head_callback(struct rcu_head *rhp) +{ + if (unlikely(!rhp->func)) + kmem_dump_obj(rhp); +} + extern int rcu_cpu_stall_suppress_at_boot; static inline bool rcu_stall_is_suppressed_at_boot(void) @@ -255,6 +262,8 @@ static inline bool rcu_stall_is_suppressed_at_boot(void) return rcu_cpu_stall_suppress_at_boot && !rcu_inkernel_boot_has_ended(); } +extern int rcu_cpu_stall_notifiers; + #ifdef CONFIG_RCU_STALL_COMMON extern int rcu_cpu_stall_ftrace_dump; @@ -570,10 +579,6 @@ void do_trace_rcu_torture_read(const char *rcutorturename, static inline void rcu_gp_set_torture_wait(int duration) { } #endif -#if IS_ENABLED(CONFIG_RCU_TORTURE_TEST) || IS_MODULE(CONFIG_RCU_TORTURE_TEST) -long rcutorture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask); -#endif - #ifdef CONFIG_TINY_SRCU static inline void srcutorture_get_gp_data(enum rcutorture_type test_type, @@ -656,4 +661,10 @@ static inline bool rcu_cpu_beenfullyonline(int cpu) { return true; } bool rcu_cpu_beenfullyonline(int cpu); #endif +#if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER) +int rcu_stall_notifier_call_chain(unsigned long val, void *v); +#else // #if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER) +static inline int rcu_stall_notifier_call_chain(unsigned long val, void *v) { return NOTIFY_DONE; } +#endif // #else // #if defined(CONFIG_RCU_STALL_COMMON) && defined(CONFIG_RCU_CPU_STALL_NOTIFIER) + #endif /* __LINUX_RCU_H */ diff --git a/kernel/rcu/rcu_segcblist.c b/kernel/rcu/rcu_segcblist.c index f71fac422c..1693ea22ef 100644 --- a/kernel/rcu/rcu_segcblist.c +++ b/kernel/rcu/rcu_segcblist.c @@ -368,7 +368,7 @@ bool rcu_segcblist_entrain(struct rcu_segcblist *rsclp, smp_mb(); /* Ensure counts are updated before callback is entrained. */ rhp->next = NULL; for (i = RCU_NEXT_TAIL; i > RCU_DONE_TAIL; i--) - if (rsclp->tails[i] != rsclp->tails[i - 1]) + if (!rcu_segcblist_segempty(rsclp, i)) break; rcu_segcblist_inc_seglen(rsclp, i); WRITE_ONCE(*rsclp->tails[i], rhp); @@ -551,7 +551,7 @@ bool rcu_segcblist_accelerate(struct rcu_segcblist *rsclp, unsigned long seq) * as their ->gp_seq[] grace-period completion sequence number. */ for (i = RCU_NEXT_READY_TAIL; i > RCU_DONE_TAIL; i--) - if (rsclp->tails[i] != rsclp->tails[i - 1] && + if (!rcu_segcblist_segempty(rsclp, i) && ULONG_CMP_LT(rsclp->gp_seq[i], seq)) break; diff --git a/kernel/rcu/rcutorture.c b/kernel/rcu/rcutorture.c index ade42d6a9d..07a6a183c5 100644 --- a/kernel/rcu/rcutorture.c +++ b/kernel/rcu/rcutorture.c @@ -21,6 +21,7 @@ #include <linux/spinlock.h> #include <linux/smp.h> #include <linux/rcupdate_wait.h> +#include <linux/rcu_notifier.h> #include <linux/interrupt.h> #include <linux/sched/signal.h> #include <uapi/linux/sched/types.h> @@ -810,7 +811,7 @@ static void synchronize_rcu_trivial(void) int cpu; for_each_online_cpu(cpu) { - rcutorture_sched_setaffinity(current->pid, cpumask_of(cpu)); + torture_sched_setaffinity(current->pid, cpumask_of(cpu)); WARN_ON_ONCE(raw_smp_processor_id() != cpu); } } @@ -1149,7 +1150,7 @@ static int rcu_torture_boost(void *arg) mutex_unlock(&boost_mutex); break; } - schedule_timeout_uninterruptible(1); + schedule_timeout_uninterruptible(HZ / 20); } /* Go do the stutter. */ @@ -1160,7 +1161,7 @@ checkwait: if (stutter_wait("rcu_torture_boost")) /* Clean up and exit. */ while (!kthread_should_stop()) { torture_shutdown_absorb("rcu_torture_boost"); - schedule_timeout_uninterruptible(1); + schedule_timeout_uninterruptible(HZ / 20); } torture_kthread_stopping("rcu_torture_boost"); return 0; @@ -1183,7 +1184,7 @@ rcu_torture_fqs(void *arg) fqs_resume_time = jiffies + fqs_stutter * HZ; while (time_before(jiffies, fqs_resume_time) && !kthread_should_stop()) { - schedule_timeout_interruptible(1); + schedule_timeout_interruptible(HZ / 20); } fqs_burst_remaining = fqs_duration; while (fqs_burst_remaining > 0 && @@ -2126,7 +2127,7 @@ static int rcu_nocb_toggle(void *arg) VERBOSE_TOROUT_STRING("rcu_nocb_toggle task started"); while (!rcu_inkernel_boot_has_ended()) schedule_timeout_interruptible(HZ / 10); - for_each_online_cpu(cpu) + for_each_possible_cpu(cpu) maxcpu = cpu; WARN_ON(maxcpu < 0); if (toggle_interval > ULONG_MAX) @@ -2428,6 +2429,16 @@ static int rcutorture_booster_init(unsigned int cpu) return 0; } +static int rcu_torture_stall_nf(struct notifier_block *nb, unsigned long v, void *ptr) +{ + pr_info("%s: v=%lu, duration=%lu.\n", __func__, v, (unsigned long)ptr); + return NOTIFY_OK; +} + +static struct notifier_block rcu_torture_stall_block = { + .notifier_call = rcu_torture_stall_nf, +}; + /* * CPU-stall kthread. It waits as specified by stall_cpu_holdoff, then * induces a CPU stall for the time specified by stall_cpu. @@ -2435,9 +2446,16 @@ static int rcutorture_booster_init(unsigned int cpu) static int rcu_torture_stall(void *args) { int idx; + int ret; unsigned long stop_at; VERBOSE_TOROUT_STRING("rcu_torture_stall task started"); + if (rcu_cpu_stall_notifiers) { + ret = rcu_stall_chain_notifier_register(&rcu_torture_stall_block); + if (ret) + pr_info("%s: rcu_stall_chain_notifier_register() returned %d, %sexpected.\n", + __func__, ret, !IS_ENABLED(CONFIG_RCU_STALL_COMMON) ? "un" : ""); + } if (stall_cpu_holdoff > 0) { VERBOSE_TOROUT_STRING("rcu_torture_stall begin holdoff"); schedule_timeout_interruptible(stall_cpu_holdoff * HZ); @@ -2481,6 +2499,11 @@ static int rcu_torture_stall(void *args) cur_ops->readunlock(idx); } pr_alert("%s end.\n", __func__); + if (rcu_cpu_stall_notifiers && !ret) { + ret = rcu_stall_chain_notifier_unregister(&rcu_torture_stall_block); + if (ret) + pr_info("%s: rcu_stall_chain_notifier_unregister() returned %d.\n", __func__, ret); + } torture_shutdown_absorb("rcu_torture_stall"); while (!kthread_should_stop()) schedule_timeout_interruptible(10 * HZ); @@ -2899,7 +2922,7 @@ static int rcu_torture_fwd_prog(void *args) WRITE_ONCE(rcu_fwd_seq, rcu_fwd_seq + 1); } else { while (READ_ONCE(rcu_fwd_seq) == oldseq && !torture_must_stop()) - schedule_timeout_interruptible(1); + schedule_timeout_interruptible(HZ / 20); oldseq = READ_ONCE(rcu_fwd_seq); } pr_alert("%s: Starting forward-progress test %d\n", __func__, rfp->rcu_fwd_id); @@ -3200,7 +3223,7 @@ static int rcu_torture_read_exit_child(void *trsp_in) set_user_nice(current, MAX_NICE); // Minimize time between reading and exiting. while (!kthread_should_stop()) - schedule_timeout_uninterruptible(1); + schedule_timeout_uninterruptible(HZ / 20); (void)rcu_torture_one_read(trsp, -1); return 0; } @@ -3248,7 +3271,7 @@ static int rcu_torture_read_exit(void *unused) smp_mb(); // Store before wakeup. wake_up(&read_exit_wq); while (!torture_must_stop()) - schedule_timeout_uninterruptible(1); + schedule_timeout_uninterruptible(HZ / 20); torture_kthread_stopping("rcu_torture_read_exit"); return 0; } diff --git a/kernel/rcu/refscale.c b/kernel/rcu/refscale.c index 91a0fd0d4d..2c2648a3ad 100644 --- a/kernel/rcu/refscale.c +++ b/kernel/rcu/refscale.c @@ -655,12 +655,12 @@ retry: goto retry; } un_delay(udl, ndl); + b = READ_ONCE(rtsp->a); // Remember, seqlock read-side release can fail. if (!rts_release(rtsp, start)) { rcu_read_unlock(); goto retry; } - b = READ_ONCE(rtsp->a); WARN_ONCE(a != b, "Re-read of ->a changed from %u to %u.\n", a, b); b = rtsp->b; rcu_read_unlock(); @@ -1025,8 +1025,8 @@ static void ref_scale_print_module_parms(struct ref_scale_ops *cur_ops, const char *tag) { pr_alert("%s" SCALE_FLAG - "--- %s: verbose=%d shutdown=%d holdoff=%d loops=%ld nreaders=%d nruns=%d readdelay=%d\n", scale_type, tag, - verbose, shutdown, holdoff, loops, nreaders, nruns, readdelay); + "--- %s: verbose=%d verbose_batched=%d shutdown=%d holdoff=%d lookup_instances=%ld loops=%ld nreaders=%d nruns=%d readdelay=%d\n", scale_type, tag, + verbose, verbose_batched, shutdown, holdoff, lookup_instances, loops, nreaders, nruns, readdelay); } static void diff --git a/kernel/rcu/srcutiny.c b/kernel/rcu/srcutiny.c index 336af24e0f..c38e5933a5 100644 --- a/kernel/rcu/srcutiny.c +++ b/kernel/rcu/srcutiny.c @@ -138,6 +138,7 @@ void srcu_drive_gp(struct work_struct *wp) while (lh) { rhp = lh; lh = lh->next; + debug_rcu_head_callback(rhp); local_bh_disable(); rhp->func(rhp); local_bh_enable(); diff --git a/kernel/rcu/srcutree.c b/kernel/rcu/srcutree.c index 25285893e4..560e99ec53 100644 --- a/kernel/rcu/srcutree.c +++ b/kernel/rcu/srcutree.c @@ -255,29 +255,31 @@ static int init_srcu_struct_fields(struct srcu_struct *ssp, bool is_static) ssp->srcu_sup->sda_is_static = is_static; if (!is_static) ssp->sda = alloc_percpu(struct srcu_data); - if (!ssp->sda) { - if (!is_static) - kfree(ssp->srcu_sup); - return -ENOMEM; - } + if (!ssp->sda) + goto err_free_sup; init_srcu_struct_data(ssp); ssp->srcu_sup->srcu_gp_seq_needed_exp = 0; ssp->srcu_sup->srcu_last_gp_end = ktime_get_mono_fast_ns(); if (READ_ONCE(ssp->srcu_sup->srcu_size_state) == SRCU_SIZE_SMALL && SRCU_SIZING_IS_INIT()) { - if (!init_srcu_struct_nodes(ssp, GFP_ATOMIC)) { - if (!ssp->srcu_sup->sda_is_static) { - free_percpu(ssp->sda); - ssp->sda = NULL; - kfree(ssp->srcu_sup); - return -ENOMEM; - } - } else { - WRITE_ONCE(ssp->srcu_sup->srcu_size_state, SRCU_SIZE_BIG); - } + if (!init_srcu_struct_nodes(ssp, GFP_ATOMIC)) + goto err_free_sda; + WRITE_ONCE(ssp->srcu_sup->srcu_size_state, SRCU_SIZE_BIG); } ssp->srcu_sup->srcu_ssp = ssp; smp_store_release(&ssp->srcu_sup->srcu_gp_seq_needed, 0); /* Init done. */ return 0; + +err_free_sda: + if (!is_static) { + free_percpu(ssp->sda); + ssp->sda = NULL; + } +err_free_sup: + if (!is_static) { + kfree(ssp->srcu_sup); + ssp->srcu_sup = NULL; + } + return -ENOMEM; } #ifdef CONFIG_DEBUG_LOCK_ALLOC @@ -1735,6 +1737,7 @@ static void srcu_invoke_callbacks(struct work_struct *work) rhp = rcu_cblist_dequeue(&ready_cbs); for (; rhp != NULL; rhp = rcu_cblist_dequeue(&ready_cbs)) { debug_rcu_head_unqueue(rhp); + debug_rcu_head_callback(rhp); local_bh_disable(); rhp->func(rhp); local_bh_enable(); diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h index 65e000ca33..f54d5782ec 100644 --- a/kernel/rcu/tasks.h +++ b/kernel/rcu/tasks.h @@ -432,6 +432,7 @@ static void rcu_barrier_tasks_generic(struct rcu_tasks *rtp) static int rcu_tasks_need_gpcb(struct rcu_tasks *rtp) { int cpu; + int dequeue_limit; unsigned long flags; bool gpdone = poll_state_synchronize_rcu(rtp->percpu_dequeue_gpseq); long n; @@ -439,7 +440,8 @@ static int rcu_tasks_need_gpcb(struct rcu_tasks *rtp) long ncbsnz = 0; int needgpcb = 0; - for (cpu = 0; cpu < smp_load_acquire(&rtp->percpu_dequeue_lim); cpu++) { + dequeue_limit = smp_load_acquire(&rtp->percpu_dequeue_lim); + for (cpu = 0; cpu < dequeue_limit; cpu++) { struct rcu_tasks_percpu *rtpcp = per_cpu_ptr(rtp->rtpcpu, cpu); /* Advance and accelerate any new callbacks. */ @@ -538,6 +540,7 @@ static void rcu_tasks_invoke_cbs(struct rcu_tasks *rtp, struct rcu_tasks_percpu raw_spin_unlock_irqrestore_rcu_node(rtpcp, flags); len = rcl.len; for (rhp = rcu_cblist_dequeue(&rcl); rhp; rhp = rcu_cblist_dequeue(&rcl)) { + debug_rcu_head_callback(rhp); local_bh_disable(); rhp->func(rhp); local_bh_enable(); @@ -1110,7 +1113,7 @@ void rcu_barrier_tasks(void) } EXPORT_SYMBOL_GPL(rcu_barrier_tasks); -int rcu_tasks_lazy_ms = -1; +static int rcu_tasks_lazy_ms = -1; module_param(rcu_tasks_lazy_ms, int, 0444); static int __init rcu_spawn_tasks_kthread(void) @@ -2005,20 +2008,22 @@ static void test_rcu_tasks_callback(struct rcu_head *rhp) static void rcu_tasks_initiate_self_tests(void) { - pr_info("Running RCU-tasks wait API self tests\n"); #ifdef CONFIG_TASKS_RCU + pr_info("Running RCU Tasks wait API self tests\n"); tests[0].runstart = jiffies; synchronize_rcu_tasks(); call_rcu_tasks(&tests[0].rh, test_rcu_tasks_callback); #endif #ifdef CONFIG_TASKS_RUDE_RCU + pr_info("Running RCU Tasks Rude wait API self tests\n"); tests[1].runstart = jiffies; synchronize_rcu_tasks_rude(); call_rcu_tasks_rude(&tests[1].rh, test_rcu_tasks_callback); #endif #ifdef CONFIG_TASKS_TRACE_RCU + pr_info("Running RCU Tasks Trace wait API self tests\n"); tests[2].runstart = jiffies; synchronize_rcu_tasks_trace(); call_rcu_tasks_trace(&tests[2].rh, test_rcu_tasks_callback); diff --git a/kernel/rcu/tiny.c b/kernel/rcu/tiny.c index 42f7589e51..fec804b790 100644 --- a/kernel/rcu/tiny.c +++ b/kernel/rcu/tiny.c @@ -97,6 +97,7 @@ static inline bool rcu_reclaim_tiny(struct rcu_head *head) trace_rcu_invoke_callback("", head); f = head->func; + debug_rcu_head_callback(head); WRITE_ONCE(head->func, (rcu_callback_t)0L); f(head); rcu_lock_release(&rcu_callback_map); diff --git a/kernel/rcu/tree.c b/kernel/rcu/tree.c index 4fe47ed95e..157f3ca2a9 100644 --- a/kernel/rcu/tree.c +++ b/kernel/rcu/tree.c @@ -1298,7 +1298,7 @@ EXPORT_SYMBOL_GPL(rcu_gp_slow_register); /* Unregister a counter, with NULL for not caring which. */ void rcu_gp_slow_unregister(atomic_t *rgssp) { - WARN_ON_ONCE(rgssp && rgssp != rcu_gp_slow_suppress); + WARN_ON_ONCE(rgssp && rgssp != rcu_gp_slow_suppress && rcu_gp_slow_suppress != NULL); WRITE_ONCE(rcu_gp_slow_suppress, NULL); } @@ -2185,6 +2185,7 @@ static void rcu_do_batch(struct rcu_data *rdp) trace_rcu_invoke_callback(rcu_state.name, rhp); f = rhp->func; + debug_rcu_head_callback(rhp); WRITE_ONCE(rhp->func, (rcu_callback_t)0L); f(rhp); @@ -2772,7 +2773,7 @@ __call_rcu_common(struct rcu_head *head, rcu_callback_t func, bool lazy_in) */ void call_rcu_hurry(struct rcu_head *head, rcu_callback_t func) { - return __call_rcu_common(head, func, false); + __call_rcu_common(head, func, false); } EXPORT_SYMBOL_GPL(call_rcu_hurry); #endif @@ -2823,7 +2824,7 @@ EXPORT_SYMBOL_GPL(call_rcu_hurry); */ void call_rcu(struct rcu_head *head, rcu_callback_t func) { - return __call_rcu_common(head, func, IS_ENABLED(CONFIG_RCU_LAZY)); + __call_rcu_common(head, func, IS_ENABLED(CONFIG_RCU_LAZY)); } EXPORT_SYMBOL_GPL(call_rcu); @@ -3516,13 +3517,6 @@ kfree_rcu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) return freed == 0 ? SHRINK_STOP : freed; } -static struct shrinker kfree_rcu_shrinker = { - .count_objects = kfree_rcu_shrink_count, - .scan_objects = kfree_rcu_shrink_scan, - .batch = 0, - .seeks = DEFAULT_SEEKS, -}; - void __init kfree_rcu_scheduler_running(void) { int cpu; @@ -4150,6 +4144,82 @@ retry: } EXPORT_SYMBOL_GPL(rcu_barrier); +static unsigned long rcu_barrier_last_throttle; + +/** + * rcu_barrier_throttled - Do rcu_barrier(), but limit to one per second + * + * This can be thought of as guard rails around rcu_barrier() that + * permits unrestricted userspace use, at least assuming the hardware's + * try_cmpxchg() is robust. There will be at most one call per second to + * rcu_barrier() system-wide from use of this function, which means that + * callers might needlessly wait a second or three. + * + * This is intended for use by test suites to avoid OOM by flushing RCU + * callbacks from the previous test before starting the next. See the + * rcutree.do_rcu_barrier module parameter for more information. + * + * Why not simply make rcu_barrier() more scalable? That might be + * the eventual endpoint, but let's keep it simple for the time being. + * Note that the module parameter infrastructure serializes calls to a + * given .set() function, but should concurrent .set() invocation ever be + * possible, we are ready! + */ +static void rcu_barrier_throttled(void) +{ + unsigned long j = jiffies; + unsigned long old = READ_ONCE(rcu_barrier_last_throttle); + unsigned long s = rcu_seq_snap(&rcu_state.barrier_sequence); + + while (time_in_range(j, old, old + HZ / 16) || + !try_cmpxchg(&rcu_barrier_last_throttle, &old, j)) { + schedule_timeout_idle(HZ / 16); + if (rcu_seq_done(&rcu_state.barrier_sequence, s)) { + smp_mb(); /* caller's subsequent code after above check. */ + return; + } + j = jiffies; + old = READ_ONCE(rcu_barrier_last_throttle); + } + rcu_barrier(); +} + +/* + * Invoke rcu_barrier_throttled() when a rcutree.do_rcu_barrier + * request arrives. We insist on a true value to allow for possible + * future expansion. + */ +static int param_set_do_rcu_barrier(const char *val, const struct kernel_param *kp) +{ + bool b; + int ret; + + if (rcu_scheduler_active != RCU_SCHEDULER_RUNNING) + return -EAGAIN; + ret = kstrtobool(val, &b); + if (!ret && b) { + atomic_inc((atomic_t *)kp->arg); + rcu_barrier_throttled(); + atomic_dec((atomic_t *)kp->arg); + } + return ret; +} + +/* + * Output the number of outstanding rcutree.do_rcu_barrier requests. + */ +static int param_get_do_rcu_barrier(char *buffer, const struct kernel_param *kp) +{ + return sprintf(buffer, "%d\n", atomic_read((atomic_t *)kp->arg)); +} + +static const struct kernel_param_ops do_rcu_barrier_ops = { + .set = param_set_do_rcu_barrier, + .get = param_get_do_rcu_barrier, +}; +static atomic_t do_rcu_barrier; +module_param_cb(do_rcu_barrier, &do_rcu_barrier_ops, &do_rcu_barrier, 0644); + /* * Compute the mask of online CPUs for the specified rcu_node structure. * This will not be stable unless the rcu_node structure's ->lock is @@ -4204,7 +4274,7 @@ bool rcu_lockdep_current_cpu_online(void) rdp = this_cpu_ptr(&rcu_data); /* * Strictly, we care here about the case where the current CPU is - * in rcu_cpu_starting() and thus has an excuse for rdp->grpmask + * in rcutree_report_cpu_starting() and thus has an excuse for rdp->grpmask * not being up to date. So arch_spin_is_locked() might have a * false positive if it's held by some *other* CPU, but that's * OK because that just means a false *negative* on the warning. @@ -4226,25 +4296,6 @@ static bool rcu_init_invoked(void) } /* - * Near the end of the offline process. Trace the fact that this CPU - * is going offline. - */ -int rcutree_dying_cpu(unsigned int cpu) -{ - bool blkd; - struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); - struct rcu_node *rnp = rdp->mynode; - - if (!IS_ENABLED(CONFIG_HOTPLUG_CPU)) - return 0; - - blkd = !!(READ_ONCE(rnp->qsmask) & rdp->grpmask); - trace_rcu_grace_period(rcu_state.name, READ_ONCE(rnp->gp_seq), - blkd ? TPS("cpuofl-bgp") : TPS("cpuofl")); - return 0; -} - -/* * All CPUs for the specified rcu_node structure have gone offline, * and all tasks that were preempted within an RCU read-side critical * section while running on one of those CPUs have since exited their RCU @@ -4290,23 +4341,6 @@ static void rcu_cleanup_dead_rnp(struct rcu_node *rnp_leaf) } /* - * The CPU has been completely removed, and some other CPU is reporting - * this fact from process context. Do the remainder of the cleanup. - * There can only be one CPU hotplug operation at a time, so no need for - * explicit locking. - */ -int rcutree_dead_cpu(unsigned int cpu) -{ - if (!IS_ENABLED(CONFIG_HOTPLUG_CPU)) - return 0; - - WRITE_ONCE(rcu_state.n_online_cpus, rcu_state.n_online_cpus - 1); - // Stop-machine done, so allow nohz_full to disable tick. - tick_dep_clear(TICK_DEP_BIT_RCU); - return 0; -} - -/* * Propagate ->qsinitmask bits up the rcu_node tree to account for the * first CPU in a given leaf rcu_node structure coming online. The caller * must hold the corresponding leaf rcu_node ->lock with interrupts @@ -4459,29 +4493,6 @@ int rcutree_online_cpu(unsigned int cpu) } /* - * Near the beginning of the process. The CPU is still very much alive - * with pretty much all services enabled. - */ -int rcutree_offline_cpu(unsigned int cpu) -{ - unsigned long flags; - struct rcu_data *rdp; - struct rcu_node *rnp; - - rdp = per_cpu_ptr(&rcu_data, cpu); - rnp = rdp->mynode; - raw_spin_lock_irqsave_rcu_node(rnp, flags); - rnp->ffmask &= ~rdp->grpmask; - raw_spin_unlock_irqrestore_rcu_node(rnp, flags); - - rcutree_affinity_setting(cpu, cpu); - - // nohz_full CPUs need the tick for stop-machine to work quickly - tick_dep_set(TICK_DEP_BIT_RCU); - return 0; -} - -/* * Mark the specified CPU as being online so that subsequent grace periods * (both expedited and normal) will wait on it. Note that this means that * incoming CPUs are not allowed to use RCU read-side critical sections @@ -4492,8 +4503,10 @@ int rcutree_offline_cpu(unsigned int cpu) * from the incoming CPU rather than from the cpuhp_step mechanism. * This is because this function must be invoked at a precise location. * This incoming CPU must not have enabled interrupts yet. + * + * This mirrors the effects of rcutree_report_cpu_dead(). */ -void rcu_cpu_starting(unsigned int cpu) +void rcutree_report_cpu_starting(unsigned int cpu) { unsigned long mask; struct rcu_data *rdp; @@ -4547,14 +4560,21 @@ void rcu_cpu_starting(unsigned int cpu) * Note that this function is special in that it is invoked directly * from the outgoing CPU rather than from the cpuhp_step mechanism. * This is because this function must be invoked at a precise location. + * + * This mirrors the effect of rcutree_report_cpu_starting(). */ -void rcu_report_dead(unsigned int cpu) +void rcutree_report_cpu_dead(void) { - unsigned long flags, seq_flags; + unsigned long flags; unsigned long mask; - struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); + struct rcu_data *rdp = this_cpu_ptr(&rcu_data); struct rcu_node *rnp = rdp->mynode; /* Outgoing CPU's rdp & rnp. */ + /* + * IRQS must be disabled from now on and until the CPU dies, or an interrupt + * may introduce a new READ-side while it is actually off the QS masks. + */ + lockdep_assert_irqs_disabled(); // Do any dangling deferred wakeups. do_nocb_deferred_wakeup(rdp); @@ -4562,7 +4582,6 @@ void rcu_report_dead(unsigned int cpu) /* Remove outgoing CPU from mask in the leaf rcu_node structure. */ mask = rdp->grpmask; - local_irq_save(seq_flags); arch_spin_lock(&rcu_state.ofl_lock); raw_spin_lock_irqsave_rcu_node(rnp, flags); /* Enforce GP memory-order guarantee. */ rdp->rcu_ofl_gp_seq = READ_ONCE(rcu_state.gp_seq); @@ -4576,8 +4595,6 @@ void rcu_report_dead(unsigned int cpu) WRITE_ONCE(rnp->qsmaskinitnext, rnp->qsmaskinitnext & ~mask); raw_spin_unlock_irqrestore_rcu_node(rnp, flags); arch_spin_unlock(&rcu_state.ofl_lock); - local_irq_restore(seq_flags); - rdp->cpu_started = false; } @@ -4632,7 +4649,60 @@ void rcutree_migrate_callbacks(int cpu) cpu, rcu_segcblist_n_cbs(&rdp->cblist), rcu_segcblist_first_cb(&rdp->cblist)); } -#endif + +/* + * The CPU has been completely removed, and some other CPU is reporting + * this fact from process context. Do the remainder of the cleanup. + * There can only be one CPU hotplug operation at a time, so no need for + * explicit locking. + */ +int rcutree_dead_cpu(unsigned int cpu) +{ + WRITE_ONCE(rcu_state.n_online_cpus, rcu_state.n_online_cpus - 1); + // Stop-machine done, so allow nohz_full to disable tick. + tick_dep_clear(TICK_DEP_BIT_RCU); + return 0; +} + +/* + * Near the end of the offline process. Trace the fact that this CPU + * is going offline. + */ +int rcutree_dying_cpu(unsigned int cpu) +{ + bool blkd; + struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); + struct rcu_node *rnp = rdp->mynode; + + blkd = !!(READ_ONCE(rnp->qsmask) & rdp->grpmask); + trace_rcu_grace_period(rcu_state.name, READ_ONCE(rnp->gp_seq), + blkd ? TPS("cpuofl-bgp") : TPS("cpuofl")); + return 0; +} + +/* + * Near the beginning of the process. The CPU is still very much alive + * with pretty much all services enabled. + */ +int rcutree_offline_cpu(unsigned int cpu) +{ + unsigned long flags; + struct rcu_data *rdp; + struct rcu_node *rnp; + + rdp = per_cpu_ptr(&rcu_data, cpu); + rnp = rdp->mynode; + raw_spin_lock_irqsave_rcu_node(rnp, flags); + rnp->ffmask &= ~rdp->grpmask; + raw_spin_unlock_irqrestore_rcu_node(rnp, flags); + + rcutree_affinity_setting(cpu, cpu); + + // nohz_full CPUs need the tick for stop-machine to work quickly + tick_dep_set(TICK_DEP_BIT_RCU); + return 0; +} +#endif /* #ifdef CONFIG_HOTPLUG_CPU */ /* * On non-huge systems, use expedited RCU grace periods to make suspend @@ -5005,6 +5075,7 @@ static void __init kfree_rcu_batch_init(void) { int cpu; int i, j; + struct shrinker *kfree_rcu_shrinker; /* Clamp it to [0:100] seconds interval. */ if (rcu_delay_page_cache_fill_msec < 0 || @@ -5036,8 +5107,17 @@ static void __init kfree_rcu_batch_init(void) INIT_DELAYED_WORK(&krcp->page_cache_work, fill_page_cache_func); krcp->initialized = true; } - if (register_shrinker(&kfree_rcu_shrinker, "rcu-kfree")) - pr_err("Failed to register kfree_rcu() shrinker!\n"); + + kfree_rcu_shrinker = shrinker_alloc(0, "rcu-kfree"); + if (!kfree_rcu_shrinker) { + pr_err("Failed to allocate kfree_rcu() shrinker!\n"); + return; + } + + kfree_rcu_shrinker->count_objects = kfree_rcu_shrink_count; + kfree_rcu_shrinker->scan_objects = kfree_rcu_shrink_scan; + + shrinker_register(kfree_rcu_shrinker); } void __init rcu_init(void) @@ -5064,7 +5144,7 @@ void __init rcu_init(void) pm_notifier(rcu_pm_notify, 0); WARN_ON(num_online_cpus() > 1); // Only one CPU this early in boot. rcutree_prepare_cpu(cpu); - rcu_cpu_starting(cpu); + rcutree_report_cpu_starting(cpu); rcutree_online_cpu(cpu); /* Create workqueue for Tree SRCU and for expedited GPs. */ diff --git a/kernel/rcu/tree_exp.h b/kernel/rcu/tree_exp.h index 6e87dc764f..2ac440bc7e 100644 --- a/kernel/rcu/tree_exp.h +++ b/kernel/rcu/tree_exp.h @@ -620,10 +620,14 @@ static void synchronize_rcu_expedited_wait(void) } for (;;) { + unsigned long j; + if (synchronize_rcu_expedited_wait_once(jiffies_stall)) return; if (rcu_stall_is_suppressed()) continue; + j = jiffies; + rcu_stall_notifier_call_chain(RCU_STALL_NOTIFY_EXP, (void *)(j - jiffies_start)); trace_rcu_stall_warning(rcu_state.name, TPS("ExpeditedStall")); pr_err("INFO: %s detected expedited stalls on CPUs/tasks: {", rcu_state.name); @@ -646,7 +650,7 @@ static void synchronize_rcu_expedited_wait(void) } } pr_cont(" } %lu jiffies s: %lu root: %#lx/%c\n", - jiffies - jiffies_start, rcu_state.expedited_sequence, + j - jiffies_start, rcu_state.expedited_sequence, data_race(rnp_root->expmask), ".T"[!!data_race(rnp_root->exp_tasks)]); if (ndetected) { diff --git a/kernel/rcu/tree_nocb.h b/kernel/rcu/tree_nocb.h index 5598212d1f..4efbf7333d 100644 --- a/kernel/rcu/tree_nocb.h +++ b/kernel/rcu/tree_nocb.h @@ -1396,13 +1396,6 @@ lazy_rcu_shrink_scan(struct shrinker *shrink, struct shrink_control *sc) return count ? count : SHRINK_STOP; } - -static struct shrinker lazy_rcu_shrinker = { - .count_objects = lazy_rcu_shrink_count, - .scan_objects = lazy_rcu_shrink_scan, - .batch = 0, - .seeks = DEFAULT_SEEKS, -}; #endif // #ifdef CONFIG_RCU_LAZY void __init rcu_init_nohz(void) @@ -1410,6 +1403,7 @@ void __init rcu_init_nohz(void) int cpu; struct rcu_data *rdp; const struct cpumask *cpumask = NULL; + struct shrinker * __maybe_unused lazy_rcu_shrinker; #if defined(CONFIG_NO_HZ_FULL) if (tick_nohz_full_running && !cpumask_empty(tick_nohz_full_mask)) @@ -1436,8 +1430,15 @@ void __init rcu_init_nohz(void) return; #ifdef CONFIG_RCU_LAZY - if (register_shrinker(&lazy_rcu_shrinker, "rcu-lazy")) - pr_err("Failed to register lazy_rcu shrinker!\n"); + lazy_rcu_shrinker = shrinker_alloc(0, "rcu-lazy"); + if (!lazy_rcu_shrinker) { + pr_err("Failed to allocate lazy_rcu shrinker!\n"); + } else { + lazy_rcu_shrinker->count_objects = lazy_rcu_shrink_count; + lazy_rcu_shrinker->scan_objects = lazy_rcu_shrink_scan; + + shrinker_register(lazy_rcu_shrinker); + } #endif // #ifdef CONFIG_RCU_LAZY if (!cpumask_subset(rcu_nocb_mask, cpu_possible_mask)) { diff --git a/kernel/rcu/tree_stall.h b/kernel/rcu/tree_stall.h index e09f4f6242..5d66642854 100644 --- a/kernel/rcu/tree_stall.h +++ b/kernel/rcu/tree_stall.h @@ -8,6 +8,7 @@ */ #include <linux/kvm_para.h> +#include <linux/rcu_notifier.h> ////////////////////////////////////////////////////////////////////////////// // @@ -540,16 +541,16 @@ static void rcu_check_gp_kthread_starvation(void) data_race(READ_ONCE(rcu_state.gp_state)), gpk ? data_race(READ_ONCE(gpk->__state)) : ~0, cpu); if (gpk) { + struct rcu_data *rdp = per_cpu_ptr(&rcu_data, cpu); + pr_err("\tUnless %s kthread gets sufficient CPU time, OOM is now expected behavior.\n", rcu_state.name); pr_err("RCU grace-period kthread stack dump:\n"); sched_show_task(gpk); - if (cpu >= 0) { - if (cpu_is_offline(cpu)) { - pr_err("RCU GP kthread last ran on offline CPU %d.\n", cpu); - } else { - pr_err("Stack dump where RCU GP kthread last ran:\n"); - dump_cpu_task(cpu); - } + if (cpu_is_offline(cpu)) { + pr_err("RCU GP kthread last ran on offline CPU %d.\n", cpu); + } else if (!(data_race(READ_ONCE(rdp->mynode->qsmask)) & rdp->grpmask)) { + pr_err("Stack dump where RCU GP kthread last ran:\n"); + dump_cpu_task(cpu); } wake_up_process(gpk); } @@ -717,7 +718,7 @@ static void print_cpu_stall(unsigned long gps) static void check_cpu_stall(struct rcu_data *rdp) { - bool didstall = false; + bool self_detected; unsigned long gs1; unsigned long gs2; unsigned long gps; @@ -774,10 +775,10 @@ static void check_cpu_stall(struct rcu_data *rdp) return; /* No stall or GP completed since entering function. */ rnp = rdp->mynode; jn = jiffies + ULONG_MAX / 2; + self_detected = READ_ONCE(rnp->qsmask) & rdp->grpmask; if (rcu_gp_in_progress() && - (READ_ONCE(rnp->qsmask) & rdp->grpmask) && + (self_detected || ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY)) && cmpxchg(&rcu_state.jiffies_stall, js, jn) == js) { - /* * If a virtual machine is stopped by the host it can look to * the watchdog like an RCU stall. Check to see if the host @@ -786,39 +787,28 @@ static void check_cpu_stall(struct rcu_data *rdp) if (kvm_check_and_clear_guest_paused()) return; - /* We haven't checked in, so go dump stack. */ - print_cpu_stall(gps); - if (READ_ONCE(rcu_cpu_stall_ftrace_dump)) - rcu_ftrace_dump(DUMP_ALL); - didstall = true; - - } else if (rcu_gp_in_progress() && - ULONG_CMP_GE(j, js + RCU_STALL_RAT_DELAY) && - cmpxchg(&rcu_state.jiffies_stall, js, jn) == js) { - - /* - * If a virtual machine is stopped by the host it can look to - * the watchdog like an RCU stall. Check to see if the host - * stopped the vm. - */ - if (kvm_check_and_clear_guest_paused()) - return; + rcu_stall_notifier_call_chain(RCU_STALL_NOTIFY_NORM, (void *)j - gps); + if (self_detected) { + /* We haven't checked in, so go dump stack. */ + print_cpu_stall(gps); + } else { + /* They had a few time units to dump stack, so complain. */ + print_other_cpu_stall(gs2, gps); + } - /* They had a few time units to dump stack, so complain. */ - print_other_cpu_stall(gs2, gps); if (READ_ONCE(rcu_cpu_stall_ftrace_dump)) rcu_ftrace_dump(DUMP_ALL); - didstall = true; - } - if (didstall && READ_ONCE(rcu_state.jiffies_stall) == jn) { - jn = jiffies + 3 * rcu_jiffies_till_stall_check() + 3; - WRITE_ONCE(rcu_state.jiffies_stall, jn); + + if (READ_ONCE(rcu_state.jiffies_stall) == jn) { + jn = jiffies + 3 * rcu_jiffies_till_stall_check() + 3; + WRITE_ONCE(rcu_state.jiffies_stall, jn); + } } } ////////////////////////////////////////////////////////////////////////////// // -// RCU forward-progress mechanisms, including of callback invocation. +// RCU forward-progress mechanisms, including for callback invocation. /* @@ -1070,3 +1060,67 @@ static int __init rcu_sysrq_init(void) return 0; } early_initcall(rcu_sysrq_init); + +#ifdef CONFIG_RCU_CPU_STALL_NOTIFIER + +////////////////////////////////////////////////////////////////////////////// +// +// RCU CPU stall-warning notifiers + +static ATOMIC_NOTIFIER_HEAD(rcu_cpu_stall_notifier_list); + +/** + * rcu_stall_chain_notifier_register - Add an RCU CPU stall notifier + * @n: Entry to add. + * + * Adds an RCU CPU stall notifier to an atomic notifier chain. + * The @action passed to a notifier will be @RCU_STALL_NOTIFY_NORM or + * friends. The @data will be the duration of the stalled grace period, + * in jiffies, coerced to a void* pointer. + * + * Returns 0 on success, %-EEXIST on error. + */ +int rcu_stall_chain_notifier_register(struct notifier_block *n) +{ + int rcsn = rcu_cpu_stall_notifiers; + + WARN(1, "Adding %pS() to RCU stall notifier list (%s).\n", n->notifier_call, + rcsn ? "possibly suppressing RCU CPU stall warnings" : "failed, so all is well"); + if (rcsn) + return atomic_notifier_chain_register(&rcu_cpu_stall_notifier_list, n); + return -EEXIST; +} +EXPORT_SYMBOL_GPL(rcu_stall_chain_notifier_register); + +/** + * rcu_stall_chain_notifier_unregister - Remove an RCU CPU stall notifier + * @n: Entry to add. + * + * Removes an RCU CPU stall notifier from an atomic notifier chain. + * + * Returns zero on success, %-ENOENT on failure. + */ +int rcu_stall_chain_notifier_unregister(struct notifier_block *n) +{ + return atomic_notifier_chain_unregister(&rcu_cpu_stall_notifier_list, n); +} +EXPORT_SYMBOL_GPL(rcu_stall_chain_notifier_unregister); + +/* + * rcu_stall_notifier_call_chain - Call functions in an RCU CPU stall notifier chain + * @val: Value passed unmodified to notifier function + * @v: Pointer passed unmodified to notifier function + * + * Calls each function in the RCU CPU stall notifier chain in turn, which + * is an atomic call chain. See atomic_notifier_call_chain() for more + * information. + * + * This is for use within RCU, hence the omission of the extra asterisk + * to indicate a non-kerneldoc format header comment. + */ +int rcu_stall_notifier_call_chain(unsigned long val, void *v) +{ + return atomic_notifier_call_chain(&rcu_cpu_stall_notifier_list, val, v); +} + +#endif // #ifdef CONFIG_RCU_CPU_STALL_NOTIFIER diff --git a/kernel/rcu/update.c b/kernel/rcu/update.c index 19bf6fa3ee..46aaaa9fe3 100644 --- a/kernel/rcu/update.c +++ b/kernel/rcu/update.c @@ -25,6 +25,7 @@ #include <linux/interrupt.h> #include <linux/sched/signal.h> #include <linux/sched/debug.h> +#include <linux/torture.h> #include <linux/atomic.h> #include <linux/bitops.h> #include <linux/percpu.h> @@ -524,22 +525,28 @@ EXPORT_SYMBOL_GPL(do_trace_rcu_torture_read); do { } while (0) #endif -#if IS_ENABLED(CONFIG_RCU_TORTURE_TEST) || IS_MODULE(CONFIG_RCU_TORTURE_TEST) +#if IS_ENABLED(CONFIG_RCU_TORTURE_TEST) || IS_MODULE(CONFIG_RCU_TORTURE_TEST) || IS_ENABLED(CONFIG_LOCK_TORTURE_TEST) || IS_MODULE(CONFIG_LOCK_TORTURE_TEST) /* Get rcutorture access to sched_setaffinity(). */ -long rcutorture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask) +long torture_sched_setaffinity(pid_t pid, const struct cpumask *in_mask) { int ret; ret = sched_setaffinity(pid, in_mask); - WARN_ONCE(ret, "%s: sched_setaffinity() returned %d\n", __func__, ret); + WARN_ONCE(ret, "%s: sched_setaffinity(%d) returned %d\n", __func__, pid, ret); return ret; } -EXPORT_SYMBOL_GPL(rcutorture_sched_setaffinity); +EXPORT_SYMBOL_GPL(torture_sched_setaffinity); #endif +int rcu_cpu_stall_notifiers __read_mostly; // !0 = provide stall notifiers (rarely useful) +EXPORT_SYMBOL_GPL(rcu_cpu_stall_notifiers); + #ifdef CONFIG_RCU_STALL_COMMON int rcu_cpu_stall_ftrace_dump __read_mostly; module_param(rcu_cpu_stall_ftrace_dump, int, 0644); +#ifdef CONFIG_RCU_CPU_STALL_NOTIFIER +module_param(rcu_cpu_stall_notifiers, int, 0444); +#endif // #ifdef CONFIG_RCU_CPU_STALL_NOTIFIER int rcu_cpu_stall_suppress __read_mostly; // !0 = suppress stall warnings. EXPORT_SYMBOL_GPL(rcu_cpu_stall_suppress); module_param(rcu_cpu_stall_suppress, int, 0644); diff --git a/kernel/reboot.c b/kernel/reboot.c index 6ebef11c88..395a0ea3c7 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -55,6 +55,7 @@ struct sys_off_handler { enum sys_off_mode mode; bool blocking; void *list; + struct device *dev; }; /* @@ -324,6 +325,7 @@ static int sys_off_notify(struct notifier_block *nb, data.cb_data = handler->cb_data; data.mode = mode; data.cmd = cmd; + data.dev = handler->dev; return handler->sys_off_cb(&data); } @@ -511,6 +513,7 @@ int devm_register_sys_off_handler(struct device *dev, handler = register_sys_off_handler(mode, priority, callback, cb_data); if (IS_ERR(handler)) return PTR_ERR(handler); + handler->dev = dev; return devm_add_action_or_reset(dev, devm_unregister_sys_off_handler, handler); diff --git a/kernel/resource.c b/kernel/resource.c index e3f5680a56..91be1bc50b 100644 --- a/kernel/resource.c +++ b/kernel/resource.c @@ -56,33 +56,17 @@ struct resource_constraint { static DEFINE_RWLOCK(resource_lock); -static struct resource *next_resource(struct resource *p) +static struct resource *next_resource(struct resource *p, bool skip_children) { - if (p->child) + if (!skip_children && p->child) return p->child; while (!p->sibling && p->parent) p = p->parent; return p->sibling; } -static struct resource *next_resource_skip_children(struct resource *p) -{ - while (!p->sibling && p->parent) - p = p->parent; - return p->sibling; -} - #define for_each_resource(_root, _p, _skip_children) \ - for ((_p) = (_root)->child; (_p); \ - (_p) = (_skip_children) ? next_resource_skip_children(_p) : \ - next_resource(_p)) - -static void *r_next(struct seq_file *m, void *v, loff_t *pos) -{ - struct resource *p = v; - (*pos)++; - return (void *)next_resource(p); -} + for ((_p) = (_root)->child; (_p); (_p) = next_resource(_p, _skip_children)) #ifdef CONFIG_PROC_FS @@ -91,14 +75,28 @@ enum { MAX_IORES_LEVEL = 5 }; static void *r_start(struct seq_file *m, loff_t *pos) __acquires(resource_lock) { - struct resource *p = pde_data(file_inode(m->file)); - loff_t l = 0; + struct resource *root = pde_data(file_inode(m->file)); + struct resource *p; + loff_t l = *pos; + read_lock(&resource_lock); - for (p = p->child; p && l < *pos; p = r_next(m, p, &l)) - ; + for_each_resource(root, p, false) { + if (l-- == 0) + break; + } + return p; } +static void *r_next(struct seq_file *m, void *v, loff_t *pos) +{ + struct resource *p = v; + + (*pos)++; + + return (void *)next_resource(p, false); +} + static void r_stop(struct seq_file *m, void *v) __releases(resource_lock) { @@ -336,7 +334,7 @@ static int find_next_iomem_res(resource_size_t start, resource_size_t end, read_lock(&resource_lock); - for (p = iomem_resource.child; p; p = next_resource(p)) { + for_each_resource(&iomem_resource, p, false) { /* If we passed the resource we are looking for, stop */ if (p->start > end) { p = NULL; @@ -1641,13 +1639,12 @@ __setup("reserve=", reserve_setup); */ int iomem_map_sanity_check(resource_size_t addr, unsigned long size) { - struct resource *p = &iomem_resource; resource_size_t end = addr + size - 1; + struct resource *p; int err = 0; - loff_t l; read_lock(&resource_lock); - for (p = p->child; p ; p = r_next(NULL, p, &l)) { + for_each_resource(&iomem_resource, p, false) { /* * We can probably skip the resources without * IORESOURCE_IO attribute? diff --git a/kernel/sched/build_utility.c b/kernel/sched/build_utility.c index 99bdd96f45..80a3df49ab 100644 --- a/kernel/sched/build_utility.c +++ b/kernel/sched/build_utility.c @@ -34,7 +34,6 @@ #include <linux/nospec.h> #include <linux/proc_fs.h> #include <linux/psi.h> -#include <linux/psi.h> #include <linux/ptrace_api.h> #include <linux/sched_clock.h> #include <linux/security.h> diff --git a/kernel/sched/core.c b/kernel/sched/core.c index a854b71836..a708d225c2 100644 --- a/kernel/sched/core.c +++ b/kernel/sched/core.c @@ -85,7 +85,6 @@ #include "sched.h" #include "stats.h" -#include "autogroup.h" #include "autogroup.h" #include "pelt.h" @@ -114,6 +113,7 @@ EXPORT_TRACEPOINT_SYMBOL_GPL(sched_overutilized_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_cfs_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_util_est_se_tp); EXPORT_TRACEPOINT_SYMBOL_GPL(sched_update_nr_running_tp); +EXPORT_TRACEPOINT_SYMBOL_GPL(sched_compute_energy_tp); DEFINE_PER_CPU_SHARED_ALIGNED(struct rq, runqueues); @@ -919,14 +919,13 @@ static bool set_nr_if_polling(struct task_struct *p) struct thread_info *ti = task_thread_info(p); typeof(ti->flags) val = READ_ONCE(ti->flags); - for (;;) { + do { if (!(val & _TIF_POLLING_NRFLAG)) return false; if (val & _TIF_NEED_RESCHED) return true; - if (try_cmpxchg(&ti->flags, &val, val | _TIF_NEED_RESCHED)) - break; - } + } while (!try_cmpxchg(&ti->flags, &val, val | _TIF_NEED_RESCHED)); + return true; } @@ -1480,16 +1479,12 @@ static void __uclamp_update_util_min_rt_default(struct task_struct *p) static void uclamp_update_util_min_rt_default(struct task_struct *p) { - struct rq_flags rf; - struct rq *rq; - if (!rt_task(p)) return; /* Protect updates to p->uclamp_* */ - rq = task_rq_lock(p, &rf); + guard(task_rq_lock)(p); __uclamp_update_util_min_rt_default(p); - task_rq_unlock(rq, p, &rf); } static inline struct uclamp_se @@ -1785,9 +1780,8 @@ static void uclamp_update_root_tg(void) uclamp_se_set(&tg->uclamp_req[UCLAMP_MAX], sysctl_sched_uclamp_util_max, false); - rcu_read_lock(); + guard(rcu)(); cpu_util_update_eff(&root_task_group.css); - rcu_read_unlock(); } #else static void uclamp_update_root_tg(void) { } @@ -1814,10 +1808,9 @@ static void uclamp_sync_util_min_rt_default(void) smp_mb__after_spinlock(); read_unlock(&tasklist_lock); - rcu_read_lock(); + guard(rcu)(); for_each_process_thread(g, p) uclamp_update_util_min_rt_default(p); - rcu_read_unlock(); } static int sysctl_sched_uclamp_handler(struct ctl_table *table, int write, @@ -2218,10 +2211,10 @@ static inline void check_class_changed(struct rq *rq, struct task_struct *p, p->sched_class->prio_changed(rq, p, oldprio); } -void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags) +void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags) { if (p->sched_class == rq->curr->sched_class) - rq->curr->sched_class->check_preempt_curr(rq, p, flags); + rq->curr->sched_class->wakeup_preempt(rq, p, flags); else if (sched_class_above(p->sched_class, rq->curr->sched_class)) resched_curr(rq); @@ -2239,31 +2232,21 @@ int __task_state_match(struct task_struct *p, unsigned int state) if (READ_ONCE(p->__state) & state) return 1; -#ifdef CONFIG_PREEMPT_RT if (READ_ONCE(p->saved_state) & state) return -1; -#endif + return 0; } static __always_inline int task_state_match(struct task_struct *p, unsigned int state) { -#ifdef CONFIG_PREEMPT_RT - int match; - /* - * Serialize against current_save_and_set_rtlock_wait_state() and - * current_restore_rtlock_saved_state(). + * Serialize against current_save_and_set_rtlock_wait_state(), + * current_restore_rtlock_saved_state(), and __refrigerator(). */ - raw_spin_lock_irq(&p->pi_lock); - match = __task_state_match(p, state); - raw_spin_unlock_irq(&p->pi_lock); - - return match; -#else + guard(raw_spinlock_irq)(&p->pi_lock); return __task_state_match(p, state); -#endif } /* @@ -2417,10 +2400,9 @@ void migrate_disable(void) return; } - preempt_disable(); + guard(preempt)(); this_rq()->nr_pinned++; p->migration_disabled = 1; - preempt_enable(); } EXPORT_SYMBOL_GPL(migrate_disable); @@ -2444,7 +2426,7 @@ void migrate_enable(void) * Ensure stop_task runs either before or after this, and that * __set_cpus_allowed_ptr(SCA_MIGRATE_ENABLE) doesn't schedule(). */ - preempt_disable(); + guard(preempt)(); if (p->cpus_ptr != &p->cpus_mask) __set_cpus_allowed_ptr(p, &ac); /* @@ -2455,7 +2437,6 @@ void migrate_enable(void) barrier(); p->migration_disabled = 0; this_rq()->nr_pinned--; - preempt_enable(); } EXPORT_SYMBOL_GPL(migrate_enable); @@ -2527,7 +2508,7 @@ static struct rq *move_queued_task(struct rq *rq, struct rq_flags *rf, rq_lock(rq, rf); WARN_ON_ONCE(task_cpu(p) != new_cpu); activate_task(rq, p, 0); - check_preempt_curr(rq, p, 0); + wakeup_preempt(rq, p, 0); return rq; } @@ -3413,7 +3394,7 @@ static void __migrate_swap_task(struct task_struct *p, int cpu) deactivate_task(src_rq, p, 0); set_task_cpu(p, cpu); activate_task(dst_rq, p, 0); - check_preempt_curr(dst_rq, p, 0); + wakeup_preempt(dst_rq, p, 0); rq_unpin_lock(dst_rq, &drf); rq_unpin_lock(src_rq, &srf); @@ -3520,13 +3501,11 @@ out: */ void kick_process(struct task_struct *p) { - int cpu; + guard(preempt)(); + int cpu = task_cpu(p); - preempt_disable(); - cpu = task_cpu(p); if ((cpu != smp_processor_id()) && task_curr(p)) smp_send_reschedule(cpu); - preempt_enable(); } EXPORT_SYMBOL_GPL(kick_process); @@ -3789,7 +3768,7 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags, } activate_task(rq, p, en_flags); - check_preempt_curr(rq, p, wake_flags); + wakeup_preempt(rq, p, wake_flags); ttwu_do_wakeup(p); @@ -3813,9 +3792,6 @@ ttwu_do_activate(struct rq *rq, struct task_struct *p, int wake_flags, if (rq->avg_idle > max) rq->avg_idle = max; - rq->wake_stamp = jiffies; - rq->wake_avg_idle = rq->avg_idle / 2; - rq->idle_stamp = 0; } #endif @@ -3860,7 +3836,7 @@ static int ttwu_runnable(struct task_struct *p, int wake_flags) * it should preempt the task that is current now. */ update_rq_clock(rq); - check_preempt_curr(rq, p, wake_flags); + wakeup_preempt(rq, p, wake_flags); } ttwu_do_wakeup(p); ret = 1; @@ -3960,6 +3936,18 @@ bool cpus_share_cache(int this_cpu, int that_cpu) return per_cpu(sd_llc_id, this_cpu) == per_cpu(sd_llc_id, that_cpu); } +/* + * Whether CPUs are share cache resources, which means LLC on non-cluster + * machines and LLC tag or L2 on machines with clusters. + */ +bool cpus_share_resources(int this_cpu, int that_cpu) +{ + if (this_cpu == that_cpu) + return true; + + return per_cpu(sd_share_id, this_cpu) == per_cpu(sd_share_id, that_cpu); +} + static inline bool ttwu_queue_cond(struct task_struct *p, int cpu) { /* @@ -4040,13 +4028,17 @@ static void ttwu_queue(struct task_struct *p, int cpu, int wake_flags) * The caller holds p::pi_lock if p != current or has preemption * disabled when p == current. * - * The rules of PREEMPT_RT saved_state: + * The rules of saved_state: * * The related locking code always holds p::pi_lock when updating * p::saved_state, which means the code is fully serialized in both cases. * - * The lock wait and lock wakeups happen via TASK_RTLOCK_WAIT. No other - * bits set. This allows to distinguish all wakeup scenarios. + * For PREEMPT_RT, the lock wait and lock wakeups happen via TASK_RTLOCK_WAIT. + * No other bits set. This allows to distinguish all wakeup scenarios. + * + * For FREEZER, the wakeup happens via TASK_FROZEN. No other bits set. This + * allows us to prevent early wakeup of tasks before they can be run on + * asymmetric ISA architectures (eg ARMv9). */ static __always_inline bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success) @@ -4060,13 +4052,13 @@ bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success) *success = !!(match = __task_state_match(p, state)); -#ifdef CONFIG_PREEMPT_RT /* * Saved state preserves the task state across blocking on - * an RT lock. If the state matches, set p::saved_state to - * TASK_RUNNING, but do not wake the task because it waits - * for a lock wakeup. Also indicate success because from - * the regular waker's point of view this has succeeded. + * an RT lock or TASK_FREEZABLE tasks. If the state matches, + * set p::saved_state to TASK_RUNNING, but do not wake the task + * because it waits for a lock wakeup or __thaw_task(). Also + * indicate success because from the regular waker's point of + * view this has succeeded. * * After acquiring the lock the task will restore p::__state * from p::saved_state which ensures that the regular @@ -4076,7 +4068,7 @@ bool ttwu_state_match(struct task_struct *p, unsigned int state, int *success) */ if (match < 0) p->saved_state = TASK_RUNNING; -#endif + return match > 0; } @@ -4258,7 +4250,7 @@ int try_to_wake_up(struct task_struct *p, unsigned int state, int wake_flags) * Pairs with the LOCK+smp_mb__after_spinlock() on rq->lock in * __schedule(). See the comment for smp_mb__after_spinlock(). * - * A similar smb_rmb() lives in try_invoke_on_locked_down_task(). + * A similar smp_rmb() lives in __task_needs_rq_lock(). */ smp_rmb(); if (READ_ONCE(p->on_rq) && ttwu_runnable(p, wake_flags)) @@ -4875,7 +4867,7 @@ void wake_up_new_task(struct task_struct *p) activate_task(rq, p, ENQUEUE_NOCLOCK); trace_sched_wakeup_new(p); - check_preempt_curr(rq, p, WF_FORK); + wakeup_preempt(rq, p, WF_FORK); #ifdef CONFIG_SMP if (p->sched_class->task_woken) { /* @@ -5918,8 +5910,7 @@ static noinline void __schedule_bug(struct task_struct *prev) print_modules(); if (irqs_disabled()) print_irqtrace_events(prev); - if (IS_ENABLED(CONFIG_DEBUG_PREEMPT) - && in_atomic_preempt_off()) { + if (IS_ENABLED(CONFIG_DEBUG_PREEMPT)) { pr_err("Preemption disabled at:"); print_ip_sym(KERN_ERR, preempt_disable_ip); } @@ -6370,8 +6361,9 @@ static void sched_core_balance(struct rq *rq) struct sched_domain *sd; int cpu = cpu_of(rq); - preempt_disable(); - rcu_read_lock(); + guard(preempt)(); + guard(rcu)(); + raw_spin_rq_unlock_irq(rq); for_each_domain(cpu, sd) { if (need_resched()) @@ -6381,8 +6373,6 @@ static void sched_core_balance(struct rq *rq) break; } raw_spin_rq_lock_irq(rq); - rcu_read_unlock(); - preempt_enable(); } static DEFINE_PER_CPU(struct balance_callback, core_balance_head); @@ -6721,22 +6711,24 @@ void __noreturn do_task_dead(void) static inline void sched_submit_work(struct task_struct *tsk) { + static DEFINE_WAIT_OVERRIDE_MAP(sched_map, LD_WAIT_CONFIG); unsigned int task_flags; - if (task_is_running(tsk)) - return; + /* + * Establish LD_WAIT_CONFIG context to ensure none of the code called + * will use a blocking primitive -- which would lead to recursion. + */ + lock_map_acquire_try(&sched_map); task_flags = tsk->flags; /* * If a worker goes to sleep, notify and ask workqueue whether it * wants to wake up a task to maintain concurrency. */ - if (task_flags & (PF_WQ_WORKER | PF_IO_WORKER)) { - if (task_flags & PF_WQ_WORKER) - wq_worker_sleeping(tsk); - else - io_wq_worker_sleeping(tsk); - } + if (task_flags & PF_WQ_WORKER) + wq_worker_sleeping(tsk); + else if (task_flags & PF_IO_WORKER) + io_wq_worker_sleeping(tsk); /* * spinlock and rwlock must not flush block requests. This will @@ -6750,6 +6742,8 @@ static inline void sched_submit_work(struct task_struct *tsk) * make sure to submit it to avoid deadlocks. */ blk_flush_plug(tsk->plug, true); + + lock_map_release(&sched_map); } static void sched_update_worker(struct task_struct *tsk) @@ -6762,16 +6756,26 @@ static void sched_update_worker(struct task_struct *tsk) } } -asmlinkage __visible void __sched schedule(void) +static __always_inline void __schedule_loop(unsigned int sched_mode) { - struct task_struct *tsk = current; - - sched_submit_work(tsk); do { preempt_disable(); - __schedule(SM_NONE); + __schedule(sched_mode); sched_preempt_enable_no_resched(); } while (need_resched()); +} + +asmlinkage __visible void __sched schedule(void) +{ + struct task_struct *tsk = current; + +#ifdef CONFIG_RT_MUTEXES + lockdep_assert(!tsk->sched_rt_mutex); +#endif + + if (!task_is_running(tsk)) + sched_submit_work(tsk); + __schedule_loop(SM_NONE); sched_update_worker(tsk); } EXPORT_SYMBOL(schedule); @@ -6835,11 +6839,7 @@ void __sched schedule_preempt_disabled(void) #ifdef CONFIG_PREEMPT_RT void __sched notrace schedule_rtlock(void) { - do { - preempt_disable(); - __schedule(SM_RTLOCK_WAIT); - sched_preempt_enable_no_resched(); - } while (need_resched()); + __schedule_loop(SM_RTLOCK_WAIT); } NOKPROBE_SYMBOL(schedule_rtlock); #endif @@ -7035,6 +7035,32 @@ static void __setscheduler_prio(struct task_struct *p, int prio) #ifdef CONFIG_RT_MUTEXES +/* + * Would be more useful with typeof()/auto_type but they don't mix with + * bit-fields. Since it's a local thing, use int. Keep the generic sounding + * name such that if someone were to implement this function we get to compare + * notes. + */ +#define fetch_and_set(x, v) ({ int _x = (x); (x) = (v); _x; }) + +void rt_mutex_pre_schedule(void) +{ + lockdep_assert(!fetch_and_set(current->sched_rt_mutex, 1)); + sched_submit_work(current); +} + +void rt_mutex_schedule(void) +{ + lockdep_assert(current->sched_rt_mutex); + __schedule_loop(SM_NONE); +} + +void rt_mutex_post_schedule(void) +{ + sched_update_worker(current); + lockdep_assert(fetch_and_set(current->sched_rt_mutex, 0)); +} + static inline int __rt_effective_prio(struct task_struct *pi_task, int prio) { if (pi_task) @@ -7188,9 +7214,8 @@ static inline int rt_effective_prio(struct task_struct *p, int prio) void set_user_nice(struct task_struct *p, long nice) { bool queued, running; - int old_prio; - struct rq_flags rf; struct rq *rq; + int old_prio; if (task_nice(p) == nice || nice < MIN_NICE || nice > MAX_NICE) return; @@ -7198,7 +7223,9 @@ void set_user_nice(struct task_struct *p, long nice) * We have to be careful, if called from sys_setpriority(), * the task might be in the middle of scheduling on another CPU. */ - rq = task_rq_lock(p, &rf); + CLASS(task_rq_lock, rq_guard)(p); + rq = rq_guard.rq; + update_rq_clock(rq); /* @@ -7209,8 +7236,9 @@ void set_user_nice(struct task_struct *p, long nice) */ if (task_has_dl_policy(p) || task_has_rt_policy(p)) { p->static_prio = NICE_TO_PRIO(nice); - goto out_unlock; + return; } + queued = task_on_rq_queued(p); running = task_current(rq, p); if (queued) @@ -7233,9 +7261,6 @@ void set_user_nice(struct task_struct *p, long nice) * lowered its priority, then reschedule its CPU: */ p->sched_class->prio_changed(rq, p, old_prio); - -out_unlock: - task_rq_unlock(rq, p, &rf); } EXPORT_SYMBOL(set_user_nice); @@ -7508,6 +7533,21 @@ static struct task_struct *find_process_by_pid(pid_t pid) return pid ? find_task_by_vpid(pid) : current; } +static struct task_struct *find_get_task(pid_t pid) +{ + struct task_struct *p; + guard(rcu)(); + + p = find_process_by_pid(pid); + if (likely(p)) + get_task_struct(p); + + return p; +} + +DEFINE_CLASS(find_get_task, struct task_struct *, if (_T) put_task_struct(_T), + find_get_task(pid), pid_t pid) + /* * sched_setparam() passes in -1 for its policy, to let the functions * it calls know not to change it. @@ -7545,14 +7585,11 @@ static void __setscheduler_params(struct task_struct *p, static bool check_same_owner(struct task_struct *p) { const struct cred *cred = current_cred(), *pcred; - bool match; + guard(rcu)(); - rcu_read_lock(); pcred = __task_cred(p); - match = (uid_eq(cred->euid, pcred->euid) || - uid_eq(cred->euid, pcred->uid)); - rcu_read_unlock(); - return match; + return (uid_eq(cred->euid, pcred->euid) || + uid_eq(cred->euid, pcred->uid)); } /* @@ -7964,27 +8001,17 @@ static int do_sched_setscheduler(pid_t pid, int policy, struct sched_param __user *param) { struct sched_param lparam; - struct task_struct *p; - int retval; if (!param || pid < 0) return -EINVAL; if (copy_from_user(&lparam, param, sizeof(struct sched_param))) return -EFAULT; - rcu_read_lock(); - retval = -ESRCH; - p = find_process_by_pid(pid); - if (likely(p)) - get_task_struct(p); - rcu_read_unlock(); - - if (likely(p)) { - retval = sched_setscheduler(p, policy, &lparam); - put_task_struct(p); - } + CLASS(find_get_task, p)(pid); + if (!p) + return -ESRCH; - return retval; + return sched_setscheduler(p, policy, &lparam); } /* @@ -8080,7 +8107,6 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, unsigned int, flags) { struct sched_attr attr; - struct task_struct *p; int retval; if (!uattr || pid < 0 || flags) @@ -8095,21 +8121,14 @@ SYSCALL_DEFINE3(sched_setattr, pid_t, pid, struct sched_attr __user *, uattr, if (attr.sched_flags & SCHED_FLAG_KEEP_POLICY) attr.sched_policy = SETPARAM_POLICY; - rcu_read_lock(); - retval = -ESRCH; - p = find_process_by_pid(pid); - if (likely(p)) - get_task_struct(p); - rcu_read_unlock(); + CLASS(find_get_task, p)(pid); + if (!p) + return -ESRCH; - if (likely(p)) { - if (attr.sched_flags & SCHED_FLAG_KEEP_PARAMS) - get_params(p, &attr); - retval = sched_setattr(p, &attr); - put_task_struct(p); - } + if (attr.sched_flags & SCHED_FLAG_KEEP_PARAMS) + get_params(p, &attr); - return retval; + return sched_setattr(p, &attr); } /** @@ -8127,16 +8146,17 @@ SYSCALL_DEFINE1(sched_getscheduler, pid_t, pid) if (pid < 0) return -EINVAL; - retval = -ESRCH; - rcu_read_lock(); + guard(rcu)(); p = find_process_by_pid(pid); - if (p) { - retval = security_task_getscheduler(p); - if (!retval) - retval = p->policy - | (p->sched_reset_on_fork ? SCHED_RESET_ON_FORK : 0); + if (!p) + return -ESRCH; + + retval = security_task_getscheduler(p); + if (!retval) { + retval = p->policy; + if (p->sched_reset_on_fork) + retval |= SCHED_RESET_ON_FORK; } - rcu_read_unlock(); return retval; } @@ -8157,30 +8177,23 @@ SYSCALL_DEFINE2(sched_getparam, pid_t, pid, struct sched_param __user *, param) if (!param || pid < 0) return -EINVAL; - rcu_read_lock(); - p = find_process_by_pid(pid); - retval = -ESRCH; - if (!p) - goto out_unlock; + scoped_guard (rcu) { + p = find_process_by_pid(pid); + if (!p) + return -ESRCH; - retval = security_task_getscheduler(p); - if (retval) - goto out_unlock; + retval = security_task_getscheduler(p); + if (retval) + return retval; - if (task_has_rt_policy(p)) - lp.sched_priority = p->rt_priority; - rcu_read_unlock(); + if (task_has_rt_policy(p)) + lp.sched_priority = p->rt_priority; + } /* * This one might sleep, we cannot do it with a spinlock held ... */ - retval = copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; - - return retval; - -out_unlock: - rcu_read_unlock(); - return retval; + return copy_to_user(param, &lp, sizeof(*param)) ? -EFAULT : 0; } /* @@ -8240,46 +8253,38 @@ SYSCALL_DEFINE4(sched_getattr, pid_t, pid, struct sched_attr __user *, uattr, usize < SCHED_ATTR_SIZE_VER0 || flags) return -EINVAL; - rcu_read_lock(); - p = find_process_by_pid(pid); - retval = -ESRCH; - if (!p) - goto out_unlock; + scoped_guard (rcu) { + p = find_process_by_pid(pid); + if (!p) + return -ESRCH; - retval = security_task_getscheduler(p); - if (retval) - goto out_unlock; + retval = security_task_getscheduler(p); + if (retval) + return retval; - kattr.sched_policy = p->policy; - if (p->sched_reset_on_fork) - kattr.sched_flags |= SCHED_FLAG_RESET_ON_FORK; - get_params(p, &kattr); - kattr.sched_flags &= SCHED_FLAG_ALL; + kattr.sched_policy = p->policy; + if (p->sched_reset_on_fork) + kattr.sched_flags |= SCHED_FLAG_RESET_ON_FORK; + get_params(p, &kattr); + kattr.sched_flags &= SCHED_FLAG_ALL; #ifdef CONFIG_UCLAMP_TASK - /* - * This could race with another potential updater, but this is fine - * because it'll correctly read the old or the new value. We don't need - * to guarantee who wins the race as long as it doesn't return garbage. - */ - kattr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value; - kattr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value; + /* + * This could race with another potential updater, but this is fine + * because it'll correctly read the old or the new value. We don't need + * to guarantee who wins the race as long as it doesn't return garbage. + */ + kattr.sched_util_min = p->uclamp_req[UCLAMP_MIN].value; + kattr.sched_util_max = p->uclamp_req[UCLAMP_MAX].value; #endif - - rcu_read_unlock(); + } return sched_attr_copy_to_user(uattr, &kattr, usize); - -out_unlock: - rcu_read_unlock(); - return retval; } #ifdef CONFIG_SMP int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) { - int ret = 0; - /* * If the task isn't a deadline task or admission control is * disabled then we don't care about affinity changes. @@ -8293,11 +8298,11 @@ int dl_task_check_affinity(struct task_struct *p, const struct cpumask *mask) * tasks allowed to run on all the CPUs in the task's * root_domain. */ - rcu_read_lock(); + guard(rcu)(); if (!cpumask_subset(task_rq(p)->rd->span, mask)) - ret = -EBUSY; - rcu_read_unlock(); - return ret; + return -EBUSY; + + return 0; } #endif @@ -8367,39 +8372,24 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) { struct affinity_context ac; struct cpumask *user_mask; - struct task_struct *p; int retval; - rcu_read_lock(); - - p = find_process_by_pid(pid); - if (!p) { - rcu_read_unlock(); + CLASS(find_get_task, p)(pid); + if (!p) return -ESRCH; - } - - /* Prevent p going away */ - get_task_struct(p); - rcu_read_unlock(); - if (p->flags & PF_NO_SETAFFINITY) { - retval = -EINVAL; - goto out_put_task; - } + if (p->flags & PF_NO_SETAFFINITY) + return -EINVAL; if (!check_same_owner(p)) { - rcu_read_lock(); - if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) { - rcu_read_unlock(); - retval = -EPERM; - goto out_put_task; - } - rcu_read_unlock(); + guard(rcu)(); + if (!ns_capable(__task_cred(p)->user_ns, CAP_SYS_NICE)) + return -EPERM; } retval = security_task_setscheduler(p); if (retval) - goto out_put_task; + return retval; /* * With non-SMP configs, user_cpus_ptr/user_mask isn't used and @@ -8409,8 +8399,7 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) if (user_mask) { cpumask_copy(user_mask, in_mask); } else if (IS_ENABLED(CONFIG_SMP)) { - retval = -ENOMEM; - goto out_put_task; + return -ENOMEM; } ac = (struct affinity_context){ @@ -8422,8 +8411,6 @@ long sched_setaffinity(pid_t pid, const struct cpumask *in_mask) retval = __sched_setaffinity(p, &ac); kfree(ac.user_mask); -out_put_task: - put_task_struct(p); return retval; } @@ -8465,28 +8452,21 @@ SYSCALL_DEFINE3(sched_setaffinity, pid_t, pid, unsigned int, len, long sched_getaffinity(pid_t pid, struct cpumask *mask) { struct task_struct *p; - unsigned long flags; int retval; - rcu_read_lock(); - - retval = -ESRCH; + guard(rcu)(); p = find_process_by_pid(pid); if (!p) - goto out_unlock; + return -ESRCH; retval = security_task_getscheduler(p); if (retval) - goto out_unlock; + return retval; - raw_spin_lock_irqsave(&p->pi_lock, flags); + guard(raw_spinlock_irqsave)(&p->pi_lock); cpumask_and(mask, &p->cpus_mask, cpu_active_mask); - raw_spin_unlock_irqrestore(&p->pi_lock, flags); - -out_unlock: - rcu_read_unlock(); - return retval; + return 0; } /** @@ -8933,55 +8913,46 @@ int __sched yield_to(struct task_struct *p, bool preempt) { struct task_struct *curr = current; struct rq *rq, *p_rq; - unsigned long flags; int yielded = 0; - local_irq_save(flags); - rq = this_rq(); + scoped_guard (irqsave) { + rq = this_rq(); again: - p_rq = task_rq(p); - /* - * If we're the only runnable task on the rq and target rq also - * has only one task, there's absolutely no point in yielding. - */ - if (rq->nr_running == 1 && p_rq->nr_running == 1) { - yielded = -ESRCH; - goto out_irq; - } + p_rq = task_rq(p); + /* + * If we're the only runnable task on the rq and target rq also + * has only one task, there's absolutely no point in yielding. + */ + if (rq->nr_running == 1 && p_rq->nr_running == 1) + return -ESRCH; - double_rq_lock(rq, p_rq); - if (task_rq(p) != p_rq) { - double_rq_unlock(rq, p_rq); - goto again; - } + guard(double_rq_lock)(rq, p_rq); + if (task_rq(p) != p_rq) + goto again; - if (!curr->sched_class->yield_to_task) - goto out_unlock; + if (!curr->sched_class->yield_to_task) + return 0; - if (curr->sched_class != p->sched_class) - goto out_unlock; + if (curr->sched_class != p->sched_class) + return 0; - if (task_on_cpu(p_rq, p) || !task_is_running(p)) - goto out_unlock; + if (task_on_cpu(p_rq, p) || !task_is_running(p)) + return 0; - yielded = curr->sched_class->yield_to_task(rq, p); - if (yielded) { - schedstat_inc(rq->yld_count); - /* - * Make p's CPU reschedule; pick_next_entity takes care of - * fairness. - */ - if (preempt && rq != p_rq) - resched_curr(p_rq); + yielded = curr->sched_class->yield_to_task(rq, p); + if (yielded) { + schedstat_inc(rq->yld_count); + /* + * Make p's CPU reschedule; pick_next_entity + * takes care of fairness. + */ + if (preempt && rq != p_rq) + resched_curr(p_rq); + } } -out_unlock: - double_rq_unlock(rq, p_rq); -out_irq: - local_irq_restore(flags); - - if (yielded > 0) + if (yielded) schedule(); return yielded; @@ -9084,38 +9055,30 @@ SYSCALL_DEFINE1(sched_get_priority_min, int, policy) static int sched_rr_get_interval(pid_t pid, struct timespec64 *t) { - struct task_struct *p; - unsigned int time_slice; - struct rq_flags rf; - struct rq *rq; + unsigned int time_slice = 0; int retval; if (pid < 0) return -EINVAL; - retval = -ESRCH; - rcu_read_lock(); - p = find_process_by_pid(pid); - if (!p) - goto out_unlock; + scoped_guard (rcu) { + struct task_struct *p = find_process_by_pid(pid); + if (!p) + return -ESRCH; - retval = security_task_getscheduler(p); - if (retval) - goto out_unlock; + retval = security_task_getscheduler(p); + if (retval) + return retval; - rq = task_rq_lock(p, &rf); - time_slice = 0; - if (p->sched_class->get_rr_interval) - time_slice = p->sched_class->get_rr_interval(rq, p); - task_rq_unlock(rq, p, &rf); + scoped_guard (task_rq_lock, p) { + struct rq *rq = scope.rq; + if (p->sched_class->get_rr_interval) + time_slice = p->sched_class->get_rr_interval(rq, p); + } + } - rcu_read_unlock(); jiffies_to_timespec64(time_slice, t); return 0; - -out_unlock: - rcu_read_unlock(); - return retval; } /** @@ -9174,9 +9137,9 @@ void sched_show_task(struct task_struct *p) if (pid_alive(p)) ppid = task_pid_nr(rcu_dereference(p->real_parent)); rcu_read_unlock(); - pr_cont(" stack:%-5lu pid:%-5d ppid:%-6d flags:0x%08lx\n", - free, task_pid_nr(p), ppid, - read_task_thread_flags(p)); + pr_cont(" stack:%-5lu pid:%-5d tgid:%-5d ppid:%-6d flags:0x%08lx\n", + free, task_pid_nr(p), task_tgid_nr(p), + ppid, read_task_thread_flags(p)); print_worker_info(KERN_INFO, p); print_stop_info(KERN_INFO, p); @@ -9906,7 +9869,7 @@ struct task_group root_task_group; LIST_HEAD(task_groups); /* Cacheline aligned slab cache for task_group */ -static struct kmem_cache *task_group_cache __read_mostly; +static struct kmem_cache *task_group_cache __ro_after_init; #endif void __init sched_init(void) @@ -10016,7 +9979,7 @@ void __init sched_init(void) #ifdef CONFIG_SMP rq->sd = NULL; rq->rd = NULL; - rq->cpu_capacity = rq->cpu_capacity_orig = SCHED_CAPACITY_SCALE; + rq->cpu_capacity = SCHED_CAPACITY_SCALE; rq->balance_callback = &balance_push_callback; rq->active_balance = 0; rq->next_balance = jiffies; @@ -10025,8 +9988,6 @@ void __init sched_init(void) rq->online = 0; rq->idle_stamp = 0; rq->avg_idle = 2*sysctl_sched_migration_cost; - rq->wake_stamp = jiffies; - rq->wake_avg_idle = rq->avg_idle; rq->max_idle_balance_cost = sysctl_sched_migration_cost; INIT_LIST_HEAD(&rq->cfs_tasks); @@ -10292,9 +10253,9 @@ void normalize_rt_tasks(void) #endif /* CONFIG_MAGIC_SYSRQ */ -#if defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) +#if defined(CONFIG_KGDB_KDB) /* - * These functions are only useful for the IA64 MCA handling, or kdb. + * These functions are only useful for kdb. * * They can only be called when the whole system has been * stopped - every CPU needs to be quiescent, and no scheduling @@ -10316,30 +10277,7 @@ struct task_struct *curr_task(int cpu) return cpu_curr(cpu); } -#endif /* defined(CONFIG_IA64) || defined(CONFIG_KGDB_KDB) */ - -#ifdef CONFIG_IA64 -/** - * ia64_set_curr_task - set the current task for a given CPU. - * @cpu: the processor in question. - * @p: the task pointer to set. - * - * Description: This function must only be used when non-maskable interrupts - * are serviced on a separate stack. It allows the architecture to switch the - * notion of the current task on a CPU in a non-blocking manner. This function - * must be called with all CPU's synchronized, and interrupts disabled, the - * and caller must save the original value of the current task (see - * curr_task() above) and restore that value before reenabling interrupts and - * re-starting the system. - * - * ONLY VALID WHEN THE WHOLE SYSTEM IS STOPPED! - */ -void ia64_set_curr_task(int cpu, struct task_struct *p) -{ - cpu_curr(cpu) = p; -} - -#endif +#endif /* defined(CONFIG_KGDB_KDB) */ #ifdef CONFIG_CGROUP_SCHED /* task_group_lock serializes the addition/removal of task groups */ @@ -10501,17 +10439,18 @@ void sched_move_task(struct task_struct *tsk) int queued, running, queue_flags = DEQUEUE_SAVE | DEQUEUE_MOVE | DEQUEUE_NOCLOCK; struct task_group *group; - struct rq_flags rf; struct rq *rq; - rq = task_rq_lock(tsk, &rf); + CLASS(task_rq_lock, rq_guard)(tsk); + rq = rq_guard.rq; + /* * Esp. with SCHED_AUTOGROUP enabled it is possible to get superfluous * group changes. */ group = sched_get_task_group(tsk); if (group == tsk->sched_task_group) - goto unlock; + return; update_rq_clock(rq); @@ -10536,9 +10475,6 @@ void sched_move_task(struct task_struct *tsk) */ resched_curr(rq); } - -unlock: - task_rq_unlock(rq, tsk, &rf); } static inline struct task_group *css_tg(struct cgroup_subsys_state *css) @@ -10575,11 +10511,9 @@ static int cpu_cgroup_css_online(struct cgroup_subsys_state *css) #ifdef CONFIG_UCLAMP_TASK_GROUP /* Propagate the effective uclamp value for the new group */ - mutex_lock(&uclamp_mutex); - rcu_read_lock(); + guard(mutex)(&uclamp_mutex); + guard(rcu)(); cpu_util_update_eff(css); - rcu_read_unlock(); - mutex_unlock(&uclamp_mutex); #endif return 0; @@ -10730,8 +10664,8 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf, static_branch_enable(&sched_uclamp_used); - mutex_lock(&uclamp_mutex); - rcu_read_lock(); + guard(mutex)(&uclamp_mutex); + guard(rcu)(); tg = css_tg(of_css(of)); if (tg->uclamp_req[clamp_id].value != req.util) @@ -10746,9 +10680,6 @@ static ssize_t cpu_uclamp_write(struct kernfs_open_file *of, char *buf, /* Update effective clamps to track the most restrictive value */ cpu_util_update_eff(of_css(of)); - rcu_read_unlock(); - mutex_unlock(&uclamp_mutex); - return nbytes; } @@ -10774,10 +10705,10 @@ static inline void cpu_uclamp_print(struct seq_file *sf, u64 percent; u32 rem; - rcu_read_lock(); - tg = css_tg(seq_css(sf)); - util_clamp = tg->uclamp_req[clamp_id].value; - rcu_read_unlock(); + scoped_guard (rcu) { + tg = css_tg(seq_css(sf)); + util_clamp = tg->uclamp_req[clamp_id].value; + } if (util_clamp == SCHED_CAPACITY_SCALE) { seq_puts(sf, "max\n"); @@ -10868,11 +10799,12 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota, * Prevent race between setting of cfs_rq->runtime_enabled and * unthrottle_offline_cfs_rqs(). */ - cpus_read_lock(); - mutex_lock(&cfs_constraints_mutex); + guard(cpus_read_lock)(); + guard(mutex)(&cfs_constraints_mutex); + ret = __cfs_schedulable(tg, period, quota); if (ret) - goto out_unlock; + return ret; runtime_enabled = quota != RUNTIME_INF; runtime_was_enabled = cfs_b->quota != RUNTIME_INF; @@ -10882,39 +10814,38 @@ static int tg_set_cfs_bandwidth(struct task_group *tg, u64 period, u64 quota, */ if (runtime_enabled && !runtime_was_enabled) cfs_bandwidth_usage_inc(); - raw_spin_lock_irq(&cfs_b->lock); - cfs_b->period = ns_to_ktime(period); - cfs_b->quota = quota; - cfs_b->burst = burst; - __refill_cfs_bandwidth_runtime(cfs_b); + scoped_guard (raw_spinlock_irq, &cfs_b->lock) { + cfs_b->period = ns_to_ktime(period); + cfs_b->quota = quota; + cfs_b->burst = burst; - /* Restart the period timer (if active) to handle new period expiry: */ - if (runtime_enabled) - start_cfs_bandwidth(cfs_b); + __refill_cfs_bandwidth_runtime(cfs_b); - raw_spin_unlock_irq(&cfs_b->lock); + /* + * Restart the period timer (if active) to handle new + * period expiry: + */ + if (runtime_enabled) + start_cfs_bandwidth(cfs_b); + } for_each_online_cpu(i) { struct cfs_rq *cfs_rq = tg->cfs_rq[i]; struct rq *rq = cfs_rq->rq; - struct rq_flags rf; - rq_lock_irq(rq, &rf); + guard(rq_lock_irq)(rq); cfs_rq->runtime_enabled = runtime_enabled; cfs_rq->runtime_remaining = 0; if (cfs_rq->throttled) unthrottle_cfs_rq(cfs_rq); - rq_unlock_irq(rq, &rf); } + if (runtime_was_enabled && !runtime_enabled) cfs_bandwidth_usage_dec(); -out_unlock: - mutex_unlock(&cfs_constraints_mutex); - cpus_read_unlock(); - return ret; + return 0; } static int tg_set_cfs_quota(struct task_group *tg, long cfs_quota_us) @@ -11099,7 +11030,6 @@ static int tg_cfs_schedulable_down(struct task_group *tg, void *data) static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) { - int ret; struct cfs_schedulable_data data = { .tg = tg, .period = period, @@ -11111,11 +11041,8 @@ static int __cfs_schedulable(struct task_group *tg, u64 period, u64 quota) do_div(data.quota, NSEC_PER_USEC); } - rcu_read_lock(); - ret = walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data); - rcu_read_unlock(); - - return ret; + guard(rcu)(); + return walk_tg_tree(tg_cfs_schedulable_down, tg_nop, &data); } static int cpu_cfs_stat_show(struct seq_file *sf, void *v) @@ -11720,14 +11647,12 @@ int __sched_mm_cid_migrate_from_fetch_cid(struct rq *src_rq, * are not the last task to be migrated from this cpu for this mm, so * there is no need to move src_cid to the destination cpu. */ - rcu_read_lock(); + guard(rcu)(); src_task = rcu_dereference(src_rq->curr); if (READ_ONCE(src_task->mm_cid_active) && src_task->mm == mm) { - rcu_read_unlock(); t->last_mm_cid = -1; return -1; } - rcu_read_unlock(); return src_cid; } @@ -11771,18 +11696,17 @@ int __sched_mm_cid_migrate_from_try_steal_cid(struct rq *src_rq, * the lazy-put flag, this task will be responsible for transitioning * from lazy-put flag set to MM_CID_UNSET. */ - rcu_read_lock(); - src_task = rcu_dereference(src_rq->curr); - if (READ_ONCE(src_task->mm_cid_active) && src_task->mm == mm) { - rcu_read_unlock(); - /* - * We observed an active task for this mm, there is therefore - * no point in moving this cid to the destination cpu. - */ - t->last_mm_cid = -1; - return -1; + scoped_guard (rcu) { + src_task = rcu_dereference(src_rq->curr); + if (READ_ONCE(src_task->mm_cid_active) && src_task->mm == mm) { + /* + * We observed an active task for this mm, there is therefore + * no point in moving this cid to the destination cpu. + */ + t->last_mm_cid = -1; + return -1; + } } - rcu_read_unlock(); /* * The src_cid is unused, so it can be unset. @@ -11855,7 +11779,6 @@ static void sched_mm_cid_remote_clear(struct mm_struct *mm, struct mm_cid *pcpu_ { struct rq *rq = cpu_rq(cpu); struct task_struct *t; - unsigned long flags; int cid, lazy_cid; cid = READ_ONCE(pcpu_cid->cid); @@ -11890,23 +11813,21 @@ static void sched_mm_cid_remote_clear(struct mm_struct *mm, struct mm_cid *pcpu_ * the lazy-put flag, that task will be responsible for transitioning * from lazy-put flag set to MM_CID_UNSET. */ - rcu_read_lock(); - t = rcu_dereference(rq->curr); - if (READ_ONCE(t->mm_cid_active) && t->mm == mm) { - rcu_read_unlock(); - return; + scoped_guard (rcu) { + t = rcu_dereference(rq->curr); + if (READ_ONCE(t->mm_cid_active) && t->mm == mm) + return; } - rcu_read_unlock(); /* * The cid is unused, so it can be unset. * Disable interrupts to keep the window of cid ownership without rq * lock small. */ - local_irq_save(flags); - if (try_cmpxchg(&pcpu_cid->cid, &lazy_cid, MM_CID_UNSET)) - __mm_cid_put(mm, cid); - local_irq_restore(flags); + scoped_guard (irqsave) { + if (try_cmpxchg(&pcpu_cid->cid, &lazy_cid, MM_CID_UNSET)) + __mm_cid_put(mm, cid); + } } static void sched_mm_cid_remote_clear_old(struct mm_struct *mm, int cpu) @@ -11928,14 +11849,13 @@ static void sched_mm_cid_remote_clear_old(struct mm_struct *mm, int cpu) * snapshot associated with this cid if an active task using the mm is * observed on this rq. */ - rcu_read_lock(); - curr = rcu_dereference(rq->curr); - if (READ_ONCE(curr->mm_cid_active) && curr->mm == mm) { - WRITE_ONCE(pcpu_cid->time, rq_clock); - rcu_read_unlock(); - return; + scoped_guard (rcu) { + curr = rcu_dereference(rq->curr); + if (READ_ONCE(curr->mm_cid_active) && curr->mm == mm) { + WRITE_ONCE(pcpu_cid->time, rq_clock); + return; + } } - rcu_read_unlock(); if (rq_clock < pcpu_cid->time + SCHED_MM_CID_PERIOD_NS) return; @@ -12029,7 +11949,6 @@ void task_tick_mm_cid(struct rq *rq, struct task_struct *curr) void sched_mm_cid_exit_signals(struct task_struct *t) { struct mm_struct *mm = t->mm; - struct rq_flags rf; struct rq *rq; if (!mm) @@ -12037,7 +11956,7 @@ void sched_mm_cid_exit_signals(struct task_struct *t) preempt_disable(); rq = this_rq(); - rq_lock_irqsave(rq, &rf); + guard(rq_lock_irqsave)(rq); preempt_enable_no_resched(); /* holding spinlock */ WRITE_ONCE(t->mm_cid_active, 0); /* @@ -12047,13 +11966,11 @@ void sched_mm_cid_exit_signals(struct task_struct *t) smp_mb(); mm_cid_put(mm); t->last_mm_cid = t->mm_cid = -1; - rq_unlock_irqrestore(rq, &rf); } void sched_mm_cid_before_execve(struct task_struct *t) { struct mm_struct *mm = t->mm; - struct rq_flags rf; struct rq *rq; if (!mm) @@ -12061,7 +11978,7 @@ void sched_mm_cid_before_execve(struct task_struct *t) preempt_disable(); rq = this_rq(); - rq_lock_irqsave(rq, &rf); + guard(rq_lock_irqsave)(rq); preempt_enable_no_resched(); /* holding spinlock */ WRITE_ONCE(t->mm_cid_active, 0); /* @@ -12071,13 +11988,11 @@ void sched_mm_cid_before_execve(struct task_struct *t) smp_mb(); mm_cid_put(mm); t->last_mm_cid = t->mm_cid = -1; - rq_unlock_irqrestore(rq, &rf); } void sched_mm_cid_after_execve(struct task_struct *t) { struct mm_struct *mm = t->mm; - struct rq_flags rf; struct rq *rq; if (!mm) @@ -12085,16 +12000,16 @@ void sched_mm_cid_after_execve(struct task_struct *t) preempt_disable(); rq = this_rq(); - rq_lock_irqsave(rq, &rf); - preempt_enable_no_resched(); /* holding spinlock */ - WRITE_ONCE(t->mm_cid_active, 1); - /* - * Store t->mm_cid_active before loading per-mm/cpu cid. - * Matches barrier in sched_mm_cid_remote_clear_old(). - */ - smp_mb(); - t->last_mm_cid = t->mm_cid = mm_cid_get(rq, mm); - rq_unlock_irqrestore(rq, &rf); + scoped_guard (rq_lock_irqsave, rq) { + preempt_enable_no_resched(); /* holding spinlock */ + WRITE_ONCE(t->mm_cid_active, 1); + /* + * Store t->mm_cid_active before loading per-mm/cpu cid. + * Matches barrier in sched_mm_cid_remote_clear_old(). + */ + smp_mb(); + t->last_mm_cid = t->mm_cid = mm_cid_get(rq, mm); + } rseq_set_notify_resume(t); } diff --git a/kernel/sched/cpudeadline.c b/kernel/sched/cpudeadline.c index 57c92d751b..95baa12a10 100644 --- a/kernel/sched/cpudeadline.c +++ b/kernel/sched/cpudeadline.c @@ -131,7 +131,7 @@ int cpudl_find(struct cpudl *cp, struct task_struct *p, if (!dl_task_fits_capacity(p, cpu)) { cpumask_clear_cpu(cpu, later_mask); - cap = capacity_orig_of(cpu); + cap = arch_scale_cpu_capacity(cpu); if (cap > max_cap || (cpu == task_cpu(p) && cap == max_cap)) { diff --git a/kernel/sched/cpufreq_schedutil.c b/kernel/sched/cpufreq_schedutil.c index 458d359f59..5888176354 100644 --- a/kernel/sched/cpufreq_schedutil.c +++ b/kernel/sched/cpufreq_schedutil.c @@ -556,6 +556,31 @@ static const struct kobj_type sugov_tunables_ktype = { /********************** cpufreq governor interface *********************/ +#ifdef CONFIG_ENERGY_MODEL +static void rebuild_sd_workfn(struct work_struct *work) +{ + rebuild_sched_domains_energy(); +} + +static DECLARE_WORK(rebuild_sd_work, rebuild_sd_workfn); + +/* + * EAS shouldn't be attempted without sugov, so rebuild the sched_domains + * on governor changes to make sure the scheduler knows about it. + */ +static void sugov_eas_rebuild_sd(void) +{ + /* + * When called from the cpufreq_register_driver() path, the + * cpu_hotplug_lock is already held, so use a work item to + * avoid nested locking in rebuild_sched_domains(). + */ + schedule_work(&rebuild_sd_work); +} +#else +static inline void sugov_eas_rebuild_sd(void) { }; +#endif + struct cpufreq_governor schedutil_gov; static struct sugov_policy *sugov_policy_alloc(struct cpufreq_policy *policy) @@ -710,6 +735,8 @@ static int sugov_init(struct cpufreq_policy *policy) if (ret) goto fail; + sugov_eas_rebuild_sd(); + out: mutex_unlock(&global_tunables_lock); return 0; @@ -751,6 +778,8 @@ static void sugov_exit(struct cpufreq_policy *policy) sugov_kthread_stop(sg_policy); sugov_policy_free(sg_policy); cpufreq_disable_fast_switch(policy); + + sugov_eas_rebuild_sd(); } static int sugov_start(struct cpufreq_policy *policy) @@ -768,14 +797,6 @@ static int sugov_start(struct cpufreq_policy *policy) sg_policy->need_freq_update = cpufreq_driver_test_flags(CPUFREQ_NEED_UPDATE_LIMITS); - for_each_cpu(cpu, policy->cpus) { - struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu); - - memset(sg_cpu, 0, sizeof(*sg_cpu)); - sg_cpu->cpu = cpu; - sg_cpu->sg_policy = sg_policy; - } - if (policy_is_shared(policy)) uu = sugov_update_shared; else if (policy->fast_switch_enabled && cpufreq_driver_has_adjust_perf()) @@ -786,6 +807,9 @@ static int sugov_start(struct cpufreq_policy *policy) for_each_cpu(cpu, policy->cpus) { struct sugov_cpu *sg_cpu = &per_cpu(sugov_cpu, cpu); + memset(sg_cpu, 0, sizeof(*sg_cpu)); + sg_cpu->cpu = cpu; + sg_cpu->sg_policy = sg_policy; cpufreq_add_update_util_hook(cpu, &sg_cpu->update_util, uu); } return 0; @@ -839,29 +863,3 @@ struct cpufreq_governor *cpufreq_default_governor(void) #endif cpufreq_governor_init(schedutil_gov); - -#ifdef CONFIG_ENERGY_MODEL -static void rebuild_sd_workfn(struct work_struct *work) -{ - rebuild_sched_domains_energy(); -} -static DECLARE_WORK(rebuild_sd_work, rebuild_sd_workfn); - -/* - * EAS shouldn't be attempted without sugov, so rebuild the sched_domains - * on governor changes to make sure the scheduler knows about it. - */ -void sched_cpufreq_governor_change(struct cpufreq_policy *policy, - struct cpufreq_governor *old_gov) -{ - if (old_gov == &schedutil_gov || policy->governor == &schedutil_gov) { - /* - * When called from the cpufreq_register_driver() path, the - * cpu_hotplug_lock is already held, so use a work item to - * avoid nested locking in rebuild_sched_domains(). - */ - schedule_work(&rebuild_sd_work); - } - -} -#endif diff --git a/kernel/sched/deadline.c b/kernel/sched/deadline.c index d78f2e8769..b28114478b 100644 --- a/kernel/sched/deadline.c +++ b/kernel/sched/deadline.c @@ -132,7 +132,7 @@ static inline unsigned long __dl_bw_capacity(const struct cpumask *mask) int i; for_each_cpu_and(i, mask, cpu_active_mask) - cap += capacity_orig_of(i); + cap += arch_scale_cpu_capacity(i); return cap; } @@ -144,7 +144,7 @@ static inline unsigned long __dl_bw_capacity(const struct cpumask *mask) static inline unsigned long dl_bw_capacity(int i) { if (!sched_asym_cpucap_active() && - capacity_orig_of(i) == SCHED_CAPACITY_SCALE) { + arch_scale_cpu_capacity(i) == SCHED_CAPACITY_SCALE) { return dl_bw_cpus(i) << SCHED_CAPACITY_SHIFT; } else { RCU_LOCKDEP_WARN(!rcu_read_lock_sched_held(), @@ -509,7 +509,6 @@ void init_dl_rq(struct dl_rq *dl_rq) /* zero means no -deadline tasks */ dl_rq->earliest_dl.curr = dl_rq->earliest_dl.next = 0; - dl_rq->dl_nr_migratory = 0; dl_rq->overloaded = 0; dl_rq->pushable_dl_tasks_root = RB_ROOT_CACHED; #else @@ -553,39 +552,6 @@ static inline void dl_clear_overload(struct rq *rq) cpumask_clear_cpu(rq->cpu, rq->rd->dlo_mask); } -static void update_dl_migration(struct dl_rq *dl_rq) -{ - if (dl_rq->dl_nr_migratory && dl_rq->dl_nr_running > 1) { - if (!dl_rq->overloaded) { - dl_set_overload(rq_of_dl_rq(dl_rq)); - dl_rq->overloaded = 1; - } - } else if (dl_rq->overloaded) { - dl_clear_overload(rq_of_dl_rq(dl_rq)); - dl_rq->overloaded = 0; - } -} - -static void inc_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) -{ - struct task_struct *p = dl_task_of(dl_se); - - if (p->nr_cpus_allowed > 1) - dl_rq->dl_nr_migratory++; - - update_dl_migration(dl_rq); -} - -static void dec_dl_migration(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) -{ - struct task_struct *p = dl_task_of(dl_se); - - if (p->nr_cpus_allowed > 1) - dl_rq->dl_nr_migratory--; - - update_dl_migration(dl_rq); -} - #define __node_2_pdl(node) \ rb_entry((node), struct task_struct, pushable_dl_tasks) @@ -594,6 +560,11 @@ static inline bool __pushable_less(struct rb_node *a, const struct rb_node *b) return dl_entity_preempt(&__node_2_pdl(a)->dl, &__node_2_pdl(b)->dl); } +static inline int has_pushable_dl_tasks(struct rq *rq) +{ + return !RB_EMPTY_ROOT(&rq->dl.pushable_dl_tasks_root.rb_root); +} + /* * The list of pushable -deadline task is not a plist, like in * sched_rt.c, it is an rb-tree with tasks ordered by deadline. @@ -609,6 +580,11 @@ static void enqueue_pushable_dl_task(struct rq *rq, struct task_struct *p) __pushable_less); if (leftmost) rq->dl.earliest_dl.next = p->dl.deadline; + + if (!rq->dl.overloaded) { + dl_set_overload(rq); + rq->dl.overloaded = 1; + } } static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p) @@ -625,11 +601,11 @@ static void dequeue_pushable_dl_task(struct rq *rq, struct task_struct *p) dl_rq->earliest_dl.next = __node_2_pdl(leftmost)->dl.deadline; RB_CLEAR_NODE(&p->pushable_dl_tasks); -} -static inline int has_pushable_dl_tasks(struct rq *rq) -{ - return !RB_EMPTY_ROOT(&rq->dl.pushable_dl_tasks_root.rb_root); + if (!has_pushable_dl_tasks(rq) && rq->dl.overloaded) { + dl_clear_overload(rq); + rq->dl.overloaded = 0; + } } static int push_dl_task(struct rq *rq); @@ -763,7 +739,7 @@ static inline void deadline_queue_pull_task(struct rq *rq) static void enqueue_task_dl(struct rq *rq, struct task_struct *p, int flags); static void __dequeue_task_dl(struct rq *rq, struct task_struct *p, int flags); -static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, int flags); +static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p, int flags); static inline void replenish_dl_new_period(struct sched_dl_entity *dl_se, struct rq *rq) @@ -1175,7 +1151,7 @@ static enum hrtimer_restart dl_task_timer(struct hrtimer *timer) enqueue_task_dl(rq, p, ENQUEUE_REPLENISH); if (dl_task(rq->curr)) - check_preempt_curr_dl(rq, p, 0); + wakeup_preempt_dl(rq, p, 0); else resched_curr(rq); @@ -1504,7 +1480,6 @@ void inc_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) add_nr_running(rq_of_dl_rq(dl_rq), 1); inc_dl_deadline(dl_rq, deadline); - inc_dl_migration(dl_se, dl_rq); } static inline @@ -1518,7 +1493,6 @@ void dec_dl_tasks(struct sched_dl_entity *dl_se, struct dl_rq *dl_rq) sub_nr_running(rq_of_dl_rq(dl_rq), 1); dec_dl_deadline(dl_rq, dl_se->deadline); - dec_dl_migration(dl_se, dl_rq); } static inline bool __dl_less(struct rb_node *a, const struct rb_node *b) @@ -1939,7 +1913,7 @@ static int balance_dl(struct rq *rq, struct task_struct *p, struct rq_flags *rf) * Only called when both the current and waking task are -deadline * tasks. */ -static void check_preempt_curr_dl(struct rq *rq, struct task_struct *p, +static void wakeup_preempt_dl(struct rq *rq, struct task_struct *p, int flags) { if (dl_entity_preempt(&p->dl, &rq->curr->dl)) { @@ -2291,9 +2265,6 @@ static int push_dl_task(struct rq *rq) struct rq *later_rq; int ret = 0; - if (!rq->dl.overloaded) - return 0; - next_task = pick_next_pushable_dl_task(rq); if (!next_task) return 0; @@ -2654,7 +2625,7 @@ static void switched_to_dl(struct rq *rq, struct task_struct *p) deadline_queue_push_tasks(rq); #endif if (dl_task(rq->curr)) - check_preempt_curr_dl(rq, p, 0); + wakeup_preempt_dl(rq, p, 0); else resched_curr(rq); } else { @@ -2723,7 +2694,7 @@ DEFINE_SCHED_CLASS(dl) = { .dequeue_task = dequeue_task_dl, .yield_task = yield_task_dl, - .check_preempt_curr = check_preempt_curr_dl, + .wakeup_preempt = wakeup_preempt_dl, .pick_next_task = pick_next_task_dl, .put_prev_task = put_prev_task_dl, diff --git a/kernel/sched/debug.c b/kernel/sched/debug.c index 4c3d0d9f3d..4580a45070 100644 --- a/kernel/sched/debug.c +++ b/kernel/sched/debug.c @@ -8,7 +8,7 @@ */ /* - * This allows printing both to /proc/sched_debug and + * This allows printing both to /sys/kernel/debug/sched/debug and * to the console */ #define SEQ_printf(m, x...) \ @@ -724,9 +724,6 @@ void print_rt_rq(struct seq_file *m, int cpu, struct rt_rq *rt_rq) SEQ_printf(m, " .%-30s: %Ld.%06ld\n", #x, SPLIT_NS(rt_rq->x)) PU(rt_nr_running); -#ifdef CONFIG_SMP - PU(rt_nr_migratory); -#endif P(rt_throttled); PN(rt_time); PN(rt_runtime); @@ -748,7 +745,6 @@ void print_dl_rq(struct seq_file *m, int cpu, struct dl_rq *dl_rq) PU(dl_nr_running); #ifdef CONFIG_SMP - PU(dl_nr_migratory); dl_bw = &cpu_rq(cpu)->rd->dl_bw; #else dl_bw = &dl_rq->dl_bw; @@ -864,7 +860,6 @@ static void sched_debug_header(struct seq_file *m) #define PN(x) \ SEQ_printf(m, " .%-40s: %Ld.%06ld\n", #x, SPLIT_NS(x)) PN(sysctl_sched_base_slice); - P(sysctl_sched_child_runs_first); P(sysctl_sched_features); #undef PN #undef P diff --git a/kernel/sched/fair.c b/kernel/sched/fair.c index d336af9cba..7ac9f4b1d9 100644 --- a/kernel/sched/fair.c +++ b/kernel/sched/fair.c @@ -51,8 +51,6 @@ #include <asm/switch_to.h> -#include <linux/sched/cond_resched.h> - #include "sched.h" #include "stats.h" #include "autogroup.h" @@ -78,12 +76,6 @@ unsigned int sysctl_sched_tunable_scaling = SCHED_TUNABLESCALING_LOG; unsigned int sysctl_sched_base_slice = 750000ULL; static unsigned int normalized_sysctl_sched_base_slice = 750000ULL; -/* - * After fork, child runs first. If set to 0 (default) then - * parent will (try to) run first. - */ -unsigned int sysctl_sched_child_runs_first __read_mostly; - const_debug unsigned int sysctl_sched_migration_cost = 500000UL; int sched_thermal_decay_shift; @@ -145,13 +137,6 @@ static unsigned int sysctl_numa_balancing_promote_rate_limit = 65536; #ifdef CONFIG_SYSCTL static struct ctl_table sched_fair_sysctls[] = { - { - .procname = "sched_child_runs_first", - .data = &sysctl_sched_child_runs_first, - .maxlen = sizeof(unsigned int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, #ifdef CONFIG_CFS_BANDWIDTH { .procname = "sched_cfs_bandwidth_slice_us", @@ -1774,12 +1759,12 @@ static bool pgdat_free_space_enough(struct pglist_data *pgdat) * The smaller the hint page fault latency, the higher the possibility * for the page to be hot. */ -static int numa_hint_fault_latency(struct page *page) +static int numa_hint_fault_latency(struct folio *folio) { int last_time, time; time = jiffies_to_msecs(jiffies); - last_time = xchg_page_access_time(page, time); + last_time = folio_xchg_access_time(folio, time); return (time - last_time) & PAGE_ACCESS_TIME_MASK; } @@ -1836,7 +1821,7 @@ static void numa_promotion_adjust_threshold(struct pglist_data *pgdat, } } -bool should_numa_migrate_memory(struct task_struct *p, struct page * page, +bool should_numa_migrate_memory(struct task_struct *p, struct folio *folio, int src_nid, int dst_cpu) { struct numa_group *ng = deref_curr_numa_group(p); @@ -1866,16 +1851,16 @@ bool should_numa_migrate_memory(struct task_struct *p, struct page * page, numa_promotion_adjust_threshold(pgdat, rate_limit, def_th); th = pgdat->nbp_threshold ? : def_th; - latency = numa_hint_fault_latency(page); + latency = numa_hint_fault_latency(folio); if (latency >= th) return false; return !numa_promotion_rate_limit(pgdat, rate_limit, - thp_nr_pages(page)); + folio_nr_pages(folio)); } this_cpupid = cpu_pid_to_cpupid(dst_cpu, current->pid); - last_cpupid = page_cpupid_xchg_last(page, this_cpupid); + last_cpupid = folio_xchg_last_cpupid(folio, this_cpupid); if (!(sysctl_numa_balancing_mode & NUMA_BALANCING_MEMORY_TIERING) && !node_is_toptier(src_nid) && !cpupid_valid(last_cpupid)) @@ -2899,19 +2884,7 @@ static void task_numa_placement(struct task_struct *p) } /* Cannot migrate task to CPU-less node */ - if (max_nid != NUMA_NO_NODE && !node_state(max_nid, N_CPU)) { - int near_nid = max_nid; - int distance, near_distance = INT_MAX; - - for_each_node_state(nid, N_CPU) { - distance = node_distance(max_nid, nid); - if (distance < near_distance) { - near_nid = nid; - near_distance = distance; - } - } - max_nid = near_nid; - } + max_nid = numa_nearest_node(max_nid, N_CPU); if (ng) { numa_group_count_active_nodes(ng); @@ -3182,7 +3155,7 @@ static void reset_ptenuma_scan(struct task_struct *p) p->mm->numa_scan_offset = 0; } -static bool vma_is_accessed(struct vm_area_struct *vma) +static bool vma_is_accessed(struct mm_struct *mm, struct vm_area_struct *vma) { unsigned long pids; /* @@ -3191,11 +3164,23 @@ static bool vma_is_accessed(struct vm_area_struct *vma) * This is also done to avoid any side effect of task scanning * amplifying the unfairness of disjoint set of VMAs' access. */ - if (READ_ONCE(current->mm->numa_scan_seq) < 2) + if ((READ_ONCE(current->mm->numa_scan_seq) - vma->numab_state->start_scan_seq) < 2) + return true; + + pids = vma->numab_state->pids_active[0] | vma->numab_state->pids_active[1]; + if (test_bit(hash_32(current->pid, ilog2(BITS_PER_LONG)), &pids)) + return true; + + /* + * Complete a scan that has already started regardless of PID access, or + * some VMAs may never be scanned in multi-threaded applications: + */ + if (mm->numa_scan_offset > vma->vm_start) { + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_IGNORE_PID); return true; + } - pids = vma->numab_state->access_pids[0] | vma->numab_state->access_pids[1]; - return test_bit(hash_32(current->pid, ilog2(BITS_PER_LONG)), &pids); + return false; } #define VMA_PID_RESET_PERIOD (4 * sysctl_numa_balancing_scan_delay) @@ -3215,6 +3200,8 @@ static void task_numa_work(struct callback_head *work) unsigned long nr_pte_updates = 0; long pages, virtpages; struct vma_iterator vmi; + bool vma_pids_skipped; + bool vma_pids_forced = false; SCHED_WARN_ON(p != container_of(work, struct task_struct, numa_work)); @@ -3257,7 +3244,6 @@ static void task_numa_work(struct callback_head *work) */ p->node_stamp += 2 * TICK_NSEC; - start = mm->numa_scan_offset; pages = sysctl_numa_balancing_scan_size; pages <<= 20 - PAGE_SHIFT; /* MB in pages */ virtpages = pages * 8; /* Scan up to this much virtual space */ @@ -3267,6 +3253,16 @@ static void task_numa_work(struct callback_head *work) if (!mmap_read_trylock(mm)) return; + + /* + * VMAs are skipped if the current PID has not trapped a fault within + * the VMA recently. Allow scanning to be forced if there is no + * suitable VMA remaining. + */ + vma_pids_skipped = false; + +retry_pids: + start = mm->numa_scan_offset; vma_iter_init(&vmi, mm, start); vma = vma_next(&vmi); if (!vma) { @@ -3279,6 +3275,7 @@ static void task_numa_work(struct callback_head *work) do { if (!vma_migratable(vma) || !vma_policy_mof(vma) || is_vm_hugetlb_page(vma) || (vma->vm_flags & VM_MIXEDMAP)) { + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_UNSUITABLE); continue; } @@ -3289,15 +3286,19 @@ static void task_numa_work(struct callback_head *work) * as migrating the pages will be of marginal benefit. */ if (!vma->vm_mm || - (vma->vm_file && (vma->vm_flags & (VM_READ|VM_WRITE)) == (VM_READ))) + (vma->vm_file && (vma->vm_flags & (VM_READ|VM_WRITE)) == (VM_READ))) { + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_SHARED_RO); continue; + } /* * Skip inaccessible VMAs to avoid any confusion between * PROT_NONE and NUMA hinting ptes */ - if (!vma_is_accessible(vma)) + if (!vma_is_accessible(vma)) { + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_INACCESSIBLE); continue; + } /* Initialise new per-VMA NUMAB state. */ if (!vma->numab_state) { @@ -3306,12 +3307,21 @@ static void task_numa_work(struct callback_head *work) if (!vma->numab_state) continue; + vma->numab_state->start_scan_seq = mm->numa_scan_seq; + vma->numab_state->next_scan = now + msecs_to_jiffies(sysctl_numa_balancing_scan_delay); /* Reset happens after 4 times scan delay of scan start */ - vma->numab_state->next_pid_reset = vma->numab_state->next_scan + + vma->numab_state->pids_active_reset = vma->numab_state->next_scan + msecs_to_jiffies(VMA_PID_RESET_PERIOD); + + /* + * Ensure prev_scan_seq does not match numa_scan_seq, + * to prevent VMAs being skipped prematurely on the + * first scan: + */ + vma->numab_state->prev_scan_seq = mm->numa_scan_seq - 1; } /* @@ -3319,23 +3329,35 @@ static void task_numa_work(struct callback_head *work) * delay the scan for new VMAs. */ if (mm->numa_scan_seq && time_before(jiffies, - vma->numab_state->next_scan)) + vma->numab_state->next_scan)) { + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_SCAN_DELAY); continue; + } - /* Do not scan the VMA if task has not accessed */ - if (!vma_is_accessed(vma)) + /* RESET access PIDs regularly for old VMAs. */ + if (mm->numa_scan_seq && + time_after(jiffies, vma->numab_state->pids_active_reset)) { + vma->numab_state->pids_active_reset = vma->numab_state->pids_active_reset + + msecs_to_jiffies(VMA_PID_RESET_PERIOD); + vma->numab_state->pids_active[0] = READ_ONCE(vma->numab_state->pids_active[1]); + vma->numab_state->pids_active[1] = 0; + } + + /* Do not rescan VMAs twice within the same sequence. */ + if (vma->numab_state->prev_scan_seq == mm->numa_scan_seq) { + mm->numa_scan_offset = vma->vm_end; + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_SEQ_COMPLETED); continue; + } /* - * RESET access PIDs regularly for old VMAs. Resetting after checking - * vma for recent access to avoid clearing PID info before access.. + * Do not scan the VMA if task has not accessed it, unless no other + * VMA candidate exists. */ - if (mm->numa_scan_seq && - time_after(jiffies, vma->numab_state->next_pid_reset)) { - vma->numab_state->next_pid_reset = vma->numab_state->next_pid_reset + - msecs_to_jiffies(VMA_PID_RESET_PERIOD); - vma->numab_state->access_pids[0] = READ_ONCE(vma->numab_state->access_pids[1]); - vma->numab_state->access_pids[1] = 0; + if (!vma_pids_forced && !vma_is_accessed(mm, vma)) { + vma_pids_skipped = true; + trace_sched_skip_vma_numa(mm, vma, NUMAB_SKIP_PID_INACTIVE); + continue; } do { @@ -3362,8 +3384,28 @@ static void task_numa_work(struct callback_head *work) cond_resched(); } while (end != vma->vm_end); + + /* VMA scan is complete, do not scan until next sequence. */ + vma->numab_state->prev_scan_seq = mm->numa_scan_seq; + + /* + * Only force scan within one VMA at a time, to limit the + * cost of scanning a potentially uninteresting VMA. + */ + if (vma_pids_forced) + break; } for_each_vma(vmi, vma); + /* + * If no VMAs are remaining and VMAs were skipped due to the PID + * not accessing the VMA previously, then force a scan to ensure + * forward progress: + */ + if (!vma && !vma_pids_forced && vma_pids_skipped) { + vma_pids_forced = true; + goto retry_pids; + } + out: /* * It is possible to reach the end of the VMA list but the last few @@ -4047,7 +4089,8 @@ static inline bool cfs_rq_is_decayed(struct cfs_rq *cfs_rq) */ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq) { - long delta = cfs_rq->avg.load_avg - cfs_rq->tg_load_avg_contrib; + long delta; + u64 now; /* * No need to update load_avg for root_task_group as it is not used. @@ -4055,10 +4098,67 @@ static inline void update_tg_load_avg(struct cfs_rq *cfs_rq) if (cfs_rq->tg == &root_task_group) return; + /* rq has been offline and doesn't contribute to the share anymore: */ + if (!cpu_active(cpu_of(rq_of(cfs_rq)))) + return; + + /* + * For migration heavy workloads, access to tg->load_avg can be + * unbound. Limit the update rate to at most once per ms. + */ + now = sched_clock_cpu(cpu_of(rq_of(cfs_rq))); + if (now - cfs_rq->last_update_tg_load_avg < NSEC_PER_MSEC) + return; + + delta = cfs_rq->avg.load_avg - cfs_rq->tg_load_avg_contrib; if (abs(delta) > cfs_rq->tg_load_avg_contrib / 64) { atomic_long_add(delta, &cfs_rq->tg->load_avg); cfs_rq->tg_load_avg_contrib = cfs_rq->avg.load_avg; + cfs_rq->last_update_tg_load_avg = now; + } +} + +static inline void clear_tg_load_avg(struct cfs_rq *cfs_rq) +{ + long delta; + u64 now; + + /* + * No need to update load_avg for root_task_group, as it is not used. + */ + if (cfs_rq->tg == &root_task_group) + return; + + now = sched_clock_cpu(cpu_of(rq_of(cfs_rq))); + delta = 0 - cfs_rq->tg_load_avg_contrib; + atomic_long_add(delta, &cfs_rq->tg->load_avg); + cfs_rq->tg_load_avg_contrib = 0; + cfs_rq->last_update_tg_load_avg = now; +} + +/* CPU offline callback: */ +static void __maybe_unused clear_tg_offline_cfs_rqs(struct rq *rq) +{ + struct task_group *tg; + + lockdep_assert_rq_held(rq); + + /* + * The rq clock has already been updated in + * set_rq_offline(), so we should skip updating + * the rq clock again in unthrottle_cfs_rq(). + */ + rq_clock_start_loop_update(rq); + + rcu_read_lock(); + list_for_each_entry_rcu(tg, &task_groups, list) { + struct cfs_rq *cfs_rq = tg->cfs_rq[cpu_of(rq)]; + + clear_tg_load_avg(cfs_rq); } + rcu_read_unlock(); + + rq_clock_stop_loop_update(rq); } /* @@ -4357,6 +4457,8 @@ static inline bool skip_blocked_update(struct sched_entity *se) static inline void update_tg_load_avg(struct cfs_rq *cfs_rq) {} +static inline void clear_tg_offline_cfs_rqs(struct rq *rq) {} + static inline int propagate_entity_load_avg(struct sched_entity *se) { return 0; @@ -4834,7 +4936,7 @@ static inline void util_est_update(struct cfs_rq *cfs_rq, * To avoid overestimation of actual task utilization, skip updates if * we cannot grant there is idle time in this CPU. */ - if (task_util(p) > capacity_orig_of(cpu_of(rq_of(cfs_rq)))) + if (task_util(p) > arch_scale_cpu_capacity(cpu_of(rq_of(cfs_rq)))) return; /* @@ -4882,14 +4984,14 @@ static inline int util_fits_cpu(unsigned long util, return fits; /* - * We must use capacity_orig_of() for comparing against uclamp_min and + * We must use arch_scale_cpu_capacity() for comparing against uclamp_min and * uclamp_max. We only care about capacity pressure (by using * capacity_of()) for comparing against the real util. * * If a task is boosted to 1024 for example, we don't want a tiny * pressure to skew the check whether it fits a CPU or not. * - * Similarly if a task is capped to capacity_orig_of(little_cpu), it + * Similarly if a task is capped to arch_scale_cpu_capacity(little_cpu), it * should fit a little cpu even if there's some pressure. * * Only exception is for thermal pressure since it has a direct impact @@ -4901,7 +5003,7 @@ static inline int util_fits_cpu(unsigned long util, * For uclamp_max, we can tolerate a drop in performance level as the * goal is to cap the task. So it's okay if it's getting less. */ - capacity_orig = capacity_orig_of(cpu); + capacity_orig = arch_scale_cpu_capacity(cpu); capacity_orig_thermal = capacity_orig - arch_scale_thermal_pressure(cpu); /* @@ -5356,7 +5458,7 @@ set_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *se) * 4) do not run the "skip" process, if something else is available */ static struct sched_entity * -pick_next_entity(struct cfs_rq *cfs_rq, struct sched_entity *curr) +pick_next_entity(struct cfs_rq *cfs_rq) { /* * Enabling NEXT_BUDDY will affect latency but not fairness. @@ -5900,13 +6002,13 @@ static void unthrottle_cfs_rq_async(struct cfs_rq *cfs_rq) static bool distribute_cfs_runtime(struct cfs_bandwidth *cfs_b) { - struct cfs_rq *local_unthrottle = NULL; int this_cpu = smp_processor_id(); u64 runtime, remaining = 1; bool throttled = false; - struct cfs_rq *cfs_rq; + struct cfs_rq *cfs_rq, *tmp; struct rq_flags rf; struct rq *rq; + LIST_HEAD(local_unthrottle); rcu_read_lock(); list_for_each_entry_rcu(cfs_rq, &cfs_b->throttled_cfs_rq, @@ -5922,11 +6024,9 @@ static bool distribute_cfs_runtime(struct cfs_bandwidth *cfs_b) if (!cfs_rq_throttled(cfs_rq)) goto next; -#ifdef CONFIG_SMP /* Already queued for async unthrottle */ if (!list_empty(&cfs_rq->throttled_csd_list)) goto next; -#endif /* By the above checks, this should never be true */ SCHED_WARN_ON(cfs_rq->runtime_remaining > 0); @@ -5943,11 +6043,17 @@ static bool distribute_cfs_runtime(struct cfs_bandwidth *cfs_b) /* we check whether we're throttled above */ if (cfs_rq->runtime_remaining > 0) { - if (cpu_of(rq) != this_cpu || - SCHED_WARN_ON(local_unthrottle)) + if (cpu_of(rq) != this_cpu) { unthrottle_cfs_rq_async(cfs_rq); - else - local_unthrottle = cfs_rq; + } else { + /* + * We currently only expect to be unthrottling + * a single cfs_rq locally. + */ + SCHED_WARN_ON(!list_empty(&local_unthrottle)); + list_add_tail(&cfs_rq->throttled_csd_list, + &local_unthrottle); + } } else { throttled = true; } @@ -5955,15 +6061,23 @@ static bool distribute_cfs_runtime(struct cfs_bandwidth *cfs_b) next: rq_unlock_irqrestore(rq, &rf); } - rcu_read_unlock(); - if (local_unthrottle) { - rq = cpu_rq(this_cpu); + list_for_each_entry_safe(cfs_rq, tmp, &local_unthrottle, + throttled_csd_list) { + struct rq *rq = rq_of(cfs_rq); + rq_lock_irqsave(rq, &rf); - if (cfs_rq_throttled(local_unthrottle)) - unthrottle_cfs_rq(local_unthrottle); + + list_del_init(&cfs_rq->throttled_csd_list); + + if (cfs_rq_throttled(cfs_rq)) + unthrottle_cfs_rq(cfs_rq); + rq_unlock_irqrestore(rq, &rf); } + SCHED_WARN_ON(!list_empty(&local_unthrottle)); + + rcu_read_unlock(); return throttled; } @@ -6293,9 +6407,7 @@ static void init_cfs_rq_runtime(struct cfs_rq *cfs_rq) { cfs_rq->runtime_enabled = 0; INIT_LIST_HEAD(&cfs_rq->throttled_list); -#ifdef CONFIG_SMP INIT_LIST_HEAD(&cfs_rq->throttled_csd_list); -#endif } void start_cfs_bandwidth(struct cfs_bandwidth *cfs_b) @@ -7253,45 +7365,9 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool struct cpumask *cpus = this_cpu_cpumask_var_ptr(select_rq_mask); int i, cpu, idle_cpu = -1, nr = INT_MAX; struct sched_domain_shared *sd_share; - struct rq *this_rq = this_rq(); - int this = smp_processor_id(); - struct sched_domain *this_sd = NULL; - u64 time = 0; cpumask_and(cpus, sched_domain_span(sd), p->cpus_ptr); - if (sched_feat(SIS_PROP) && !has_idle_core) { - u64 avg_cost, avg_idle, span_avg; - unsigned long now = jiffies; - - this_sd = rcu_dereference(*this_cpu_ptr(&sd_llc)); - if (!this_sd) - return -1; - - /* - * If we're busy, the assumption that the last idle period - * predicts the future is flawed; age away the remaining - * predicted idle time. - */ - if (unlikely(this_rq->wake_stamp < now)) { - while (this_rq->wake_stamp < now && this_rq->wake_avg_idle) { - this_rq->wake_stamp++; - this_rq->wake_avg_idle >>= 1; - } - } - - avg_idle = this_rq->wake_avg_idle; - avg_cost = this_sd->avg_scan_cost + 1; - - span_avg = sd->span_weight * avg_idle; - if (span_avg > 4*avg_cost) - nr = div_u64(span_avg, avg_cost); - else - nr = 4; - - time = cpu_clock(this); - } - if (sched_feat(SIS_UTIL)) { sd_share = rcu_dereference(per_cpu(sd_llc_shared, target)); if (sd_share) { @@ -7303,6 +7379,30 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool } } + if (static_branch_unlikely(&sched_cluster_active)) { + struct sched_group *sg = sd->groups; + + if (sg->flags & SD_CLUSTER) { + for_each_cpu_wrap(cpu, sched_group_span(sg), target + 1) { + if (!cpumask_test_cpu(cpu, cpus)) + continue; + + if (has_idle_core) { + i = select_idle_core(p, cpu, cpus, &idle_cpu); + if ((unsigned int)i < nr_cpumask_bits) + return i; + } else { + if (--nr <= 0) + return -1; + idle_cpu = __select_idle_cpu(cpu, p); + if ((unsigned int)idle_cpu < nr_cpumask_bits) + return idle_cpu; + } + } + cpumask_andnot(cpus, cpus, sched_group_span(sg)); + } + } + for_each_cpu_wrap(cpu, cpus, target + 1) { if (has_idle_core) { i = select_idle_core(p, cpu, cpus, &idle_cpu); @@ -7310,7 +7410,7 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool return i; } else { - if (!--nr) + if (--nr <= 0) return -1; idle_cpu = __select_idle_cpu(cpu, p); if ((unsigned int)idle_cpu < nr_cpumask_bits) @@ -7321,18 +7421,6 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, bool if (has_idle_core) set_idle_cores(target, false); - if (sched_feat(SIS_PROP) && this_sd && !has_idle_core) { - time = cpu_clock(this) - time; - - /* - * Account for the scan cost of wakeups against the average - * idle time. - */ - this_rq->wake_avg_idle -= min(this_rq->wake_avg_idle, time); - - update_avg(&this_sd->avg_scan_cost, time); - } - return idle_cpu; } @@ -7372,7 +7460,7 @@ select_idle_capacity(struct task_struct *p, struct sched_domain *sd, int target) * Look for the CPU with best capacity. */ else if (fits < 0) - cpu_cap = capacity_orig_of(cpu) - thermal_load_avg(cpu_rq(cpu)); + cpu_cap = arch_scale_cpu_capacity(cpu) - thermal_load_avg(cpu_rq(cpu)); /* * First, select CPU which fits better (-1 being better than 0). @@ -7412,7 +7500,7 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) bool has_idle_core = false; struct sched_domain *sd; unsigned long task_util, util_min, util_max; - int i, recent_used_cpu; + int i, recent_used_cpu, prev_aff = -1; /* * On asymmetric system, update task utilization because we will check @@ -7439,8 +7527,14 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) */ if (prev != target && cpus_share_cache(prev, target) && (available_idle_cpu(prev) || sched_idle_cpu(prev)) && - asym_fits_cpu(task_util, util_min, util_max, prev)) - return prev; + asym_fits_cpu(task_util, util_min, util_max, prev)) { + + if (!static_branch_unlikely(&sched_cluster_active) || + cpus_share_resources(prev, target)) + return prev; + + prev_aff = prev; + } /* * Allow a per-cpu kthread to stack with the wakee if the @@ -7467,7 +7561,13 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) (available_idle_cpu(recent_used_cpu) || sched_idle_cpu(recent_used_cpu)) && cpumask_test_cpu(recent_used_cpu, p->cpus_ptr) && asym_fits_cpu(task_util, util_min, util_max, recent_used_cpu)) { - return recent_used_cpu; + + if (!static_branch_unlikely(&sched_cluster_active) || + cpus_share_resources(recent_used_cpu, target)) + return recent_used_cpu; + + } else { + recent_used_cpu = -1; } /* @@ -7508,6 +7608,17 @@ static int select_idle_sibling(struct task_struct *p, int prev, int target) if ((unsigned)i < nr_cpumask_bits) return i; + /* + * For cluster machines which have lower sharing cache like L2 or + * LLC Tag, we tend to find an idle CPU in the target's cluster + * first. But prev_cpu or recent_used_cpu may also be a good candidate, + * use them if possible when no idle CPU found in select_idle_cpu(). + */ + if ((unsigned int)prev_aff < nr_cpumask_bits) + return prev_aff; + if ((unsigned int)recent_used_cpu < nr_cpumask_bits) + return recent_used_cpu; + return target; } @@ -7614,7 +7725,7 @@ cpu_util(int cpu, struct task_struct *p, int dst_cpu, int boost) util = max(util, util_est); } - return min(util, capacity_orig_of(cpu)); + return min(util, arch_scale_cpu_capacity(cpu)); } unsigned long cpu_util_cfs(int cpu) @@ -7766,11 +7877,16 @@ compute_energy(struct energy_env *eenv, struct perf_domain *pd, { unsigned long max_util = eenv_pd_max_util(eenv, pd_cpus, p, dst_cpu); unsigned long busy_time = eenv->pd_busy_time; + unsigned long energy; if (dst_cpu >= 0) busy_time = min(eenv->pd_cap, busy_time + eenv->task_busy_time); - return em_cpu_energy(pd->em_pd, max_util, busy_time, eenv->cpu_cap); + energy = em_cpu_energy(pd->em_pd, max_util, busy_time, eenv->cpu_cap); + + trace_sched_compute_energy_tp(p, dst_cpu, energy, max_util, busy_time); + + return energy; } /* @@ -8140,7 +8256,7 @@ static void set_next_buddy(struct sched_entity *se) /* * Preempt the current task with a newly woken task if needed: */ -static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_flags) +static void check_preempt_wakeup_fair(struct rq *rq, struct task_struct *p, int wake_flags) { struct task_struct *curr = rq->curr; struct sched_entity *se = &curr->se, *pse = &p->se; @@ -8153,7 +8269,7 @@ static void check_preempt_wakeup(struct rq *rq, struct task_struct *p, int wake_ /* * This is possible from callers such as attach_tasks(), in which we - * unconditionally check_preempt_curr() after an enqueue (which may have + * unconditionally wakeup_preempt() after an enqueue (which may have * lead to a throttle). This both saves work and prevents false * next-buddy nomination below. */ @@ -8245,7 +8361,7 @@ again: goto again; } - se = pick_next_entity(cfs_rq, curr); + se = pick_next_entity(cfs_rq); cfs_rq = group_cfs_rq(se); } while (cfs_rq); @@ -8308,7 +8424,7 @@ again: } } - se = pick_next_entity(cfs_rq, curr); + se = pick_next_entity(cfs_rq); cfs_rq = group_cfs_rq(se); } while (cfs_rq); @@ -8347,7 +8463,7 @@ simple: put_prev_task(rq, prev); do { - se = pick_next_entity(cfs_rq, NULL); + se = pick_next_entity(cfs_rq); set_next_entity(cfs_rq, se); cfs_rq = group_cfs_rq(se); } while (cfs_rq); @@ -9060,7 +9176,7 @@ static void attach_task(struct rq *rq, struct task_struct *p) WARN_ON_ONCE(task_rq(p) != rq); activate_task(rq, p, ENQUEUE_NOCLOCK); - check_preempt_curr(rq, p, 0); + wakeup_preempt(rq, p, 0); } /* @@ -9400,8 +9516,6 @@ static void update_cpu_capacity(struct sched_domain *sd, int cpu) unsigned long capacity = scale_rt_capacity(cpu); struct sched_group *sdg = sd->groups; - cpu_rq(cpu)->cpu_capacity_orig = arch_scale_cpu_capacity(cpu); - if (!capacity) capacity = 1; @@ -9477,7 +9591,7 @@ static inline int check_cpu_capacity(struct rq *rq, struct sched_domain *sd) { return ((rq->cpu_capacity * sd->imbalance_pct) < - (rq->cpu_capacity_orig * 100)); + (arch_scale_cpu_capacity(cpu_of(rq)) * 100)); } /* @@ -9488,7 +9602,7 @@ check_cpu_capacity(struct rq *rq, struct sched_domain *sd) static inline int check_misfit_status(struct rq *rq, struct sched_domain *sd) { return rq->misfit_task_load && - (rq->cpu_capacity_orig < rq->rd->max_cpu_capacity || + (arch_scale_cpu_capacity(rq->cpu) < rq->rd->max_cpu_capacity || check_cpu_capacity(rq, sd)); } @@ -9640,7 +9754,7 @@ static bool sched_use_asym_prio(struct sched_domain *sd, int cpu) * can only do it if @group is an SMT group and has exactly on busy CPU. Larger * imbalances in the number of CPUS are dealt with in find_busiest_group(). * - * If we are balancing load within an SMT core, or at DIE domain level, always + * If we are balancing load within an SMT core, or at PKG domain level, always * proceed. * * Return: true if @env::dst_cpu can do with asym_packing load balance. False @@ -11659,36 +11773,39 @@ static inline int on_null_domain(struct rq *rq) #ifdef CONFIG_NO_HZ_COMMON /* - * idle load balancing details - * - When one of the busy CPUs notice that there may be an idle rebalancing + * NOHZ idle load balancing (ILB) details: + * + * - When one of the busy CPUs notices that there may be an idle rebalancing * needed, they will kick the idle load balancer, which then does idle * load balancing for all the idle CPUs. - * - HK_TYPE_MISC CPUs are used for this task, because HK_TYPE_SCHED not set + * + * - HK_TYPE_MISC CPUs are used for this task, because HK_TYPE_SCHED is not set * anywhere yet. */ - static inline int find_new_ilb(void) { - int ilb; const struct cpumask *hk_mask; + int ilb_cpu; hk_mask = housekeeping_cpumask(HK_TYPE_MISC); - for_each_cpu_and(ilb, nohz.idle_cpus_mask, hk_mask) { + for_each_cpu_and(ilb_cpu, nohz.idle_cpus_mask, hk_mask) { - if (ilb == smp_processor_id()) + if (ilb_cpu == smp_processor_id()) continue; - if (idle_cpu(ilb)) - return ilb; + if (idle_cpu(ilb_cpu)) + return ilb_cpu; } - return nr_cpu_ids; + return -1; } /* - * Kick a CPU to do the nohz balancing, if it is time for it. We pick any - * idle CPU in the HK_TYPE_MISC housekeeping set (if there is one). + * Kick a CPU to do the NOHZ balancing, if it is time for it, via a cross-CPU + * SMP function call (IPI). + * + * We pick the first idle CPU in the HK_TYPE_MISC housekeeping set (if there is one). */ static void kick_ilb(unsigned int flags) { @@ -11702,8 +11819,7 @@ static void kick_ilb(unsigned int flags) nohz.next_balance = jiffies+1; ilb_cpu = find_new_ilb(); - - if (ilb_cpu >= nr_cpu_ids) + if (ilb_cpu < 0) return; /* @@ -11716,7 +11832,7 @@ static void kick_ilb(unsigned int flags) /* * This way we generate an IPI on the target CPU which - * is idle. And the softirq performing nohz idle load balance + * is idle, and the softirq performing NOHZ idle load balancing * will be run before returning from the IPI. */ smp_call_function_single_async(ilb_cpu, &cpu_rq(ilb_cpu)->nohz_csd); @@ -11745,7 +11861,7 @@ static void nohz_balancer_kick(struct rq *rq) /* * None are in tickless mode and hence no need for NOHZ idle load - * balancing. + * balancing: */ if (likely(!atomic_read(&nohz.nr_cpus))) return; @@ -11767,9 +11883,8 @@ static void nohz_balancer_kick(struct rq *rq) sd = rcu_dereference(rq->sd); if (sd) { /* - * If there's a CFS task and the current CPU has reduced - * capacity; kick the ILB to see if there's a better CPU to run - * on. + * If there's a runnable CFS task and the current CPU has reduced + * capacity, kick the ILB to see if there's a better CPU to run on: */ if (rq->cfs.h_nr_running >= 1 && check_cpu_capacity(rq, sd)) { flags = NOHZ_STATS_KICK | NOHZ_BALANCE_KICK; @@ -11821,11 +11936,11 @@ static void nohz_balancer_kick(struct rq *rq) if (sds) { /* * If there is an imbalance between LLC domains (IOW we could - * increase the overall cache use), we need some less-loaded LLC - * domain to pull some load. Likewise, we may need to spread + * increase the overall cache utilization), we need a less-loaded LLC + * domain to pull some load from. Likewise, we may need to spread * load within the current LLC domain (e.g. packed SMT cores but * other CPUs are idle). We can't really know from here how busy - * the others are - so just get a nohz balance going if it looks + * the others are - so just get a NOHZ balance going if it looks * like this LLC domain has tasks we could move. */ nr_busy = atomic_read(&sds->nr_busy_cpus); @@ -12095,8 +12210,19 @@ static bool nohz_idle_balance(struct rq *this_rq, enum cpu_idle_type idle) } /* - * Check if we need to run the ILB for updating blocked load before entering - * idle state. + * Check if we need to directly run the ILB for updating blocked load before + * entering idle state. Here we run ILB directly without issuing IPIs. + * + * Note that when this function is called, the tick may not yet be stopped on + * this CPU yet. nohz.idle_cpus_mask is updated only when tick is stopped and + * cleared on the next busy tick. In other words, nohz.idle_cpus_mask updates + * don't align with CPUs enter/exit idle to avoid bottlenecks due to high idle + * entry/exit rate (usec). So it is possible that _nohz_idle_balance() is + * called from this function on (this) CPU that's not yet in the mask. That's + * OK because the goal of nohz_run_idle_balance() is to run ILB only for + * updating the blocked load of already idle CPUs without waking up one of + * those idle CPUs and outside the preempt disable / irq off phase of the local + * cpu about to enter idle, because it can take a long time. */ void nohz_run_idle_balance(int cpu) { @@ -12338,6 +12464,9 @@ static void rq_offline_fair(struct rq *rq) /* Ensure any throttled groups are reachable by pick_next_task */ unthrottle_offline_cfs_rqs(rq); + + /* Ensure that we remove rq contribution to group share: */ + clear_tg_offline_cfs_rqs(rq); } #endif /* CONFIG_SMP */ @@ -12541,7 +12670,7 @@ prio_changed_fair(struct rq *rq, struct task_struct *p, int oldprio) if (p->prio > oldprio) resched_curr(rq); } else - check_preempt_curr(rq, p, 0); + wakeup_preempt(rq, p, 0); } #ifdef CONFIG_FAIR_GROUP_SCHED @@ -12643,7 +12772,7 @@ static void switched_to_fair(struct rq *rq, struct task_struct *p) if (task_current(rq, p)) resched_curr(rq); else - check_preempt_curr(rq, p, 0); + wakeup_preempt(rq, p, 0); } } @@ -13002,7 +13131,7 @@ DEFINE_SCHED_CLASS(fair) = { .yield_task = yield_task_fair, .yield_to_task = yield_to_task_fair, - .check_preempt_curr = check_preempt_wakeup, + .wakeup_preempt = check_preempt_wakeup_fair, .pick_next_task = __pick_next_task_fair, .put_prev_task = put_prev_task_fair, diff --git a/kernel/sched/features.h b/kernel/sched/features.h index f770168230..a3ddf84de4 100644 --- a/kernel/sched/features.h +++ b/kernel/sched/features.h @@ -49,7 +49,6 @@ SCHED_FEAT(TTWU_QUEUE, true) /* * When doing wakeups, attempt to limit superfluous scans of the LLC domain. */ -SCHED_FEAT(SIS_PROP, false) SCHED_FEAT(SIS_UTIL, true) /* diff --git a/kernel/sched/idle.c b/kernel/sched/idle.c index 5007b25c5b..565f8374dd 100644 --- a/kernel/sched/idle.c +++ b/kernel/sched/idle.c @@ -401,7 +401,7 @@ balance_idle(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) /* * Idle tasks are unconditionally rescheduled: */ -static void check_preempt_curr_idle(struct rq *rq, struct task_struct *p, int flags) +static void wakeup_preempt_idle(struct rq *rq, struct task_struct *p, int flags) { resched_curr(rq); } @@ -482,7 +482,7 @@ DEFINE_SCHED_CLASS(idle) = { /* dequeue is not valid, we print a debug message there: */ .dequeue_task = dequeue_task_idle, - .check_preempt_curr = check_preempt_curr_idle, + .wakeup_preempt = wakeup_preempt_idle, .pick_next_task = pick_next_task_idle, .put_prev_task = put_prev_task_idle, diff --git a/kernel/sched/membarrier.c b/kernel/sched/membarrier.c index 2ad881d077..4e715b9b27 100644 --- a/kernel/sched/membarrier.c +++ b/kernel/sched/membarrier.c @@ -162,6 +162,9 @@ | MEMBARRIER_PRIVATE_EXPEDITED_RSEQ_BITMASK \ | MEMBARRIER_CMD_GET_REGISTRATIONS) +static DEFINE_MUTEX(membarrier_ipi_mutex); +#define SERIALIZE_IPI() guard(mutex)(&membarrier_ipi_mutex) + static void ipi_mb(void *info) { smp_mb(); /* IPIs should be serializing but paranoid. */ @@ -259,6 +262,7 @@ static int membarrier_global_expedited(void) if (!zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) return -ENOMEM; + SERIALIZE_IPI(); cpus_read_lock(); rcu_read_lock(); for_each_online_cpu(cpu) { @@ -347,6 +351,7 @@ static int membarrier_private_expedited(int flags, int cpu_id) if (cpu_id < 0 && !zalloc_cpumask_var(&tmpmask, GFP_KERNEL)) return -ENOMEM; + SERIALIZE_IPI(); cpus_read_lock(); if (cpu_id >= 0) { @@ -460,6 +465,7 @@ static int sync_runqueues_membarrier_state(struct mm_struct *mm) * between threads which are users of @mm has its membarrier state * updated. */ + SERIALIZE_IPI(); cpus_read_lock(); rcu_read_lock(); for_each_online_cpu(cpu) { diff --git a/kernel/sched/pelt.c b/kernel/sched/pelt.c index 0f31076826..63b6cf8982 100644 --- a/kernel/sched/pelt.c +++ b/kernel/sched/pelt.c @@ -1,6 +1,6 @@ // SPDX-License-Identifier: GPL-2.0 /* - * Per Entity Load Tracking + * Per Entity Load Tracking (PELT) * * Copyright (C) 2007 Red Hat, Inc., Ingo Molnar <mingo@redhat.com> * diff --git a/kernel/sched/psi.c b/kernel/sched/psi.c index 1d0f634725..7b4aa5809c 100644 --- a/kernel/sched/psi.c +++ b/kernel/sched/psi.c @@ -434,14 +434,13 @@ static u64 window_update(struct psi_window *win, u64 now, u64 value) return growth; } -static u64 update_triggers(struct psi_group *group, u64 now, bool *update_total, +static void update_triggers(struct psi_group *group, u64 now, enum psi_aggregators aggregator) { struct psi_trigger *t; u64 *total = group->total[aggregator]; struct list_head *triggers; u64 *aggregator_total; - *update_total = false; if (aggregator == PSI_AVGS) { triggers = &group->avg_triggers; @@ -471,14 +470,6 @@ static u64 update_triggers(struct psi_group *group, u64 now, bool *update_total, * events without dropping any). */ if (new_stall) { - /* - * Multiple triggers might be looking at the same state, - * remember to update group->polling_total[] once we've - * been through all of them. Also remember to extend the - * polling time if we see new stall activity. - */ - *update_total = true; - /* Calculate growth since last update */ growth = window_update(&t->win, now, total[t->state]); if (!t->pending_event) { @@ -503,8 +494,6 @@ static u64 update_triggers(struct psi_group *group, u64 now, bool *update_total, /* Reset threshold breach flag once event got generated */ t->pending_event = false; } - - return now + group->rtpoll_min_period; } static u64 update_averages(struct psi_group *group, u64 now) @@ -565,7 +554,6 @@ static void psi_avgs_work(struct work_struct *work) struct delayed_work *dwork; struct psi_group *group; u32 changed_states; - bool update_total; u64 now; dwork = to_delayed_work(work); @@ -584,7 +572,7 @@ static void psi_avgs_work(struct work_struct *work) * go - see calc_avgs() and missed_periods. */ if (now >= group->avg_next_update) { - update_triggers(group, now, &update_total, PSI_AVGS); + update_triggers(group, now, PSI_AVGS); group->avg_next_update = update_averages(group, now); } @@ -608,7 +596,7 @@ static void init_rtpoll_triggers(struct psi_group *group, u64 now) group->rtpoll_next_update = now + group->rtpoll_min_period; } -/* Schedule polling if it's not already scheduled or forced. */ +/* Schedule rtpolling if it's not already scheduled or forced. */ static void psi_schedule_rtpoll_work(struct psi_group *group, unsigned long delay, bool force) { @@ -640,7 +628,6 @@ static void psi_rtpoll_work(struct psi_group *group) { bool force_reschedule = false; u32 changed_states; - bool update_total; u64 now; mutex_lock(&group->rtpoll_trigger_lock); @@ -649,37 +636,37 @@ static void psi_rtpoll_work(struct psi_group *group) if (now > group->rtpoll_until) { /* - * We are either about to start or might stop polling if no - * state change was recorded. Resetting poll_scheduled leaves + * We are either about to start or might stop rtpolling if no + * state change was recorded. Resetting rtpoll_scheduled leaves * a small window for psi_group_change to sneak in and schedule - * an immediate poll_work before we get to rescheduling. One - * potential extra wakeup at the end of the polling window - * should be negligible and polling_next_update still keeps + * an immediate rtpoll_work before we get to rescheduling. One + * potential extra wakeup at the end of the rtpolling window + * should be negligible and rtpoll_next_update still keeps * updates correctly on schedule. */ atomic_set(&group->rtpoll_scheduled, 0); /* - * A task change can race with the poll worker that is supposed to + * A task change can race with the rtpoll worker that is supposed to * report on it. To avoid missing events, ensure ordering between - * poll_scheduled and the task state accesses, such that if the poll - * worker misses the state update, the task change is guaranteed to - * reschedule the poll worker: + * rtpoll_scheduled and the task state accesses, such that if the + * rtpoll worker misses the state update, the task change is + * guaranteed to reschedule the rtpoll worker: * - * poll worker: - * atomic_set(poll_scheduled, 0) + * rtpoll worker: + * atomic_set(rtpoll_scheduled, 0) * smp_mb() * LOAD states * * task change: * STORE states - * if atomic_xchg(poll_scheduled, 1) == 0: - * schedule poll worker + * if atomic_xchg(rtpoll_scheduled, 1) == 0: + * schedule rtpoll worker * * The atomic_xchg() implies a full barrier. */ smp_mb(); } else { - /* Polling window is not over, keep rescheduling */ + /* The rtpolling window is not over, keep rescheduling */ force_reschedule = true; } @@ -687,7 +674,7 @@ static void psi_rtpoll_work(struct psi_group *group) collect_percpu_times(group, PSI_POLL, &changed_states); if (changed_states & group->rtpoll_states) { - /* Initialize trigger windows when entering polling mode */ + /* Initialize trigger windows when entering rtpolling mode */ if (now > group->rtpoll_until) init_rtpoll_triggers(group, now); @@ -706,10 +693,12 @@ static void psi_rtpoll_work(struct psi_group *group) } if (now >= group->rtpoll_next_update) { - group->rtpoll_next_update = update_triggers(group, now, &update_total, PSI_POLL); - if (update_total) + if (changed_states & group->rtpoll_states) { + update_triggers(group, now, PSI_POLL); memcpy(group->rtpoll_total, group->total[PSI_POLL], sizeof(group->rtpoll_total)); + } + group->rtpoll_next_update = now + group->rtpoll_min_period; } psi_schedule_rtpoll_work(group, @@ -1009,6 +998,9 @@ void psi_account_irqtime(struct task_struct *task, u32 delta) struct psi_group_cpu *groupc; u64 now; + if (static_branch_likely(&psi_disabled)) + return; + if (!task->pid) return; diff --git a/kernel/sched/rt.c b/kernel/sched/rt.c index 904dd85345..6aaf0a3d60 100644 --- a/kernel/sched/rt.c +++ b/kernel/sched/rt.c @@ -16,7 +16,7 @@ struct rt_bandwidth def_rt_bandwidth; * period over which we measure -rt task CPU usage in us. * default: 1s */ -unsigned int sysctl_sched_rt_period = 1000000; +int sysctl_sched_rt_period = 1000000; /* * part of the period that we allow rt tasks to run in us. @@ -34,9 +34,11 @@ static struct ctl_table sched_rt_sysctls[] = { { .procname = "sched_rt_period_us", .data = &sysctl_sched_rt_period, - .maxlen = sizeof(unsigned int), + .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = SYSCTL_ONE, + .extra2 = SYSCTL_INT_MAX, }, { .procname = "sched_rt_runtime_us", @@ -44,6 +46,8 @@ static struct ctl_table sched_rt_sysctls[] = { .maxlen = sizeof(int), .mode = 0644, .proc_handler = sched_rt_handler, + .extra1 = SYSCTL_NEG_ONE, + .extra2 = (void *)&sysctl_sched_rt_period, }, { .procname = "sched_rr_timeslice_ms", @@ -143,7 +147,6 @@ void init_rt_rq(struct rt_rq *rt_rq) #if defined CONFIG_SMP rt_rq->highest_prio.curr = MAX_RT_PRIO-1; rt_rq->highest_prio.next = MAX_RT_PRIO-1; - rt_rq->rt_nr_migratory = 0; rt_rq->overloaded = 0; plist_head_init(&rt_rq->pushable_tasks); #endif /* CONFIG_SMP */ @@ -358,53 +361,6 @@ static inline void rt_clear_overload(struct rq *rq) cpumask_clear_cpu(rq->cpu, rq->rd->rto_mask); } -static void update_rt_migration(struct rt_rq *rt_rq) -{ - if (rt_rq->rt_nr_migratory && rt_rq->rt_nr_total > 1) { - if (!rt_rq->overloaded) { - rt_set_overload(rq_of_rt_rq(rt_rq)); - rt_rq->overloaded = 1; - } - } else if (rt_rq->overloaded) { - rt_clear_overload(rq_of_rt_rq(rt_rq)); - rt_rq->overloaded = 0; - } -} - -static void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) -{ - struct task_struct *p; - - if (!rt_entity_is_task(rt_se)) - return; - - p = rt_task_of(rt_se); - rt_rq = &rq_of_rt_rq(rt_rq)->rt; - - rt_rq->rt_nr_total++; - if (p->nr_cpus_allowed > 1) - rt_rq->rt_nr_migratory++; - - update_rt_migration(rt_rq); -} - -static void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) -{ - struct task_struct *p; - - if (!rt_entity_is_task(rt_se)) - return; - - p = rt_task_of(rt_se); - rt_rq = &rq_of_rt_rq(rt_rq)->rt; - - rt_rq->rt_nr_total--; - if (p->nr_cpus_allowed > 1) - rt_rq->rt_nr_migratory--; - - update_rt_migration(rt_rq); -} - static inline int has_pushable_tasks(struct rq *rq) { return !plist_head_empty(&rq->rt.pushable_tasks); @@ -438,6 +394,11 @@ static void enqueue_pushable_task(struct rq *rq, struct task_struct *p) /* Update the highest prio pushable task */ if (p->prio < rq->rt.highest_prio.next) rq->rt.highest_prio.next = p->prio; + + if (!rq->rt.overloaded) { + rt_set_overload(rq); + rq->rt.overloaded = 1; + } } static void dequeue_pushable_task(struct rq *rq, struct task_struct *p) @@ -451,6 +412,11 @@ static void dequeue_pushable_task(struct rq *rq, struct task_struct *p) rq->rt.highest_prio.next = p->prio; } else { rq->rt.highest_prio.next = MAX_RT_PRIO-1; + + if (rq->rt.overloaded) { + rt_clear_overload(rq); + rq->rt.overloaded = 0; + } } } @@ -464,16 +430,6 @@ static inline void dequeue_pushable_task(struct rq *rq, struct task_struct *p) { } -static inline -void inc_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) -{ -} - -static inline -void dec_rt_migration(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) -{ -} - static inline void rt_queue_push_tasks(struct rq *rq) { } @@ -515,7 +471,7 @@ static inline bool rt_task_fits_capacity(struct task_struct *p, int cpu) min_cap = uclamp_eff_value(p, UCLAMP_MIN); max_cap = uclamp_eff_value(p, UCLAMP_MAX); - cpu_cap = capacity_orig_of(cpu); + cpu_cap = arch_scale_cpu_capacity(cpu); return cpu_cap >= min(min_cap, max_cap); } @@ -953,7 +909,7 @@ static int do_sched_rt_period_timer(struct rt_bandwidth *rt_b, int overrun) /* * When we're idle and a woken (rt) task is - * throttled check_preempt_curr() will set + * throttled wakeup_preempt() will set * skip_update and the time between the wakeup * and this unthrottle will get accounted as * 'runtime'. @@ -1281,7 +1237,6 @@ void inc_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) rt_rq->rr_nr_running += rt_se_rr_nr_running(rt_se); inc_rt_prio(rt_rq, prio); - inc_rt_migration(rt_se, rt_rq); inc_rt_group(rt_se, rt_rq); } @@ -1294,7 +1249,6 @@ void dec_rt_tasks(struct sched_rt_entity *rt_se, struct rt_rq *rt_rq) rt_rq->rr_nr_running -= rt_se_rr_nr_running(rt_se); dec_rt_prio(rt_rq, rt_se_prio(rt_se)); - dec_rt_migration(rt_se, rt_rq); dec_rt_group(rt_se, rt_rq); } @@ -1715,7 +1669,7 @@ static int balance_rt(struct rq *rq, struct task_struct *p, struct rq_flags *rf) /* * Preempt the current task with a newly woken task if needed: */ -static void check_preempt_curr_rt(struct rq *rq, struct task_struct *p, int flags) +static void wakeup_preempt_rt(struct rq *rq, struct task_struct *p, int flags) { if (p->prio < rq->curr->prio) { resched_curr(rq); @@ -2706,7 +2660,7 @@ DEFINE_SCHED_CLASS(rt) = { .dequeue_task = dequeue_task_rt, .yield_task = yield_task_rt, - .check_preempt_curr = check_preempt_curr_rt, + .wakeup_preempt = wakeup_preempt_rt, .pick_next_task = pick_next_task_rt, .put_prev_task = put_prev_task_rt, @@ -2989,9 +2943,6 @@ static int sched_rt_global_constraints(void) #ifdef CONFIG_SYSCTL static int sched_rt_global_validate(void) { - if (sysctl_sched_rt_period <= 0) - return -EINVAL; - if ((sysctl_sched_rt_runtime != RUNTIME_INF) && ((sysctl_sched_rt_runtime > sysctl_sched_rt_period) || ((u64)sysctl_sched_rt_runtime * @@ -3022,7 +2973,7 @@ static int sched_rt_handler(struct ctl_table *table, int write, void *buffer, old_period = sysctl_sched_rt_period; old_runtime = sysctl_sched_rt_runtime; - ret = proc_dointvec(table, write, buffer, lenp, ppos); + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (!ret && write) { ret = sched_rt_global_validate(); diff --git a/kernel/sched/sched.h b/kernel/sched/sched.h index 0484627240..2e5a95486a 100644 --- a/kernel/sched/sched.h +++ b/kernel/sched/sched.h @@ -74,15 +74,6 @@ #include "../workqueue_internal.h" -#ifdef CONFIG_CGROUP_SCHED -#include <linux/cgroup.h> -#include <linux/psi.h> -#endif - -#ifdef CONFIG_SCHED_DEBUG -# include <linux/static_key.h> -#endif - #ifdef CONFIG_PARAVIRT # include <asm/paravirt.h> # include <asm/paravirt_api_clock.h> @@ -109,14 +100,12 @@ extern __read_mostly int scheduler_running; extern unsigned long calc_load_update; extern atomic_long_t calc_load_tasks; -extern unsigned int sysctl_sched_child_runs_first; - extern void calc_global_load_tick(struct rq *this_rq); extern long calc_load_fold_active(struct rq *this_rq, long adjust); extern void call_trace_sched_update_nr_running(struct rq *rq, int count); -extern unsigned int sysctl_sched_rt_period; +extern int sysctl_sched_rt_period; extern int sysctl_sched_rt_runtime; extern int sched_rr_timeslice; @@ -594,6 +583,7 @@ struct cfs_rq { } removed; #ifdef CONFIG_FAIR_GROUP_SCHED + u64 last_update_tg_load_avg; unsigned long tg_load_avg_contrib; long propagate; long prop_runnable_sum; @@ -644,9 +634,7 @@ struct cfs_rq { int throttled; int throttle_count; struct list_head throttled_list; -#ifdef CONFIG_SMP struct list_head throttled_csd_list; -#endif #endif /* CONFIG_CFS_BANDWIDTH */ #endif /* CONFIG_FAIR_GROUP_SCHED */ }; @@ -675,8 +663,6 @@ struct rt_rq { } highest_prio; #endif #ifdef CONFIG_SMP - unsigned int rt_nr_migratory; - unsigned int rt_nr_total; int overloaded; struct plist_head pushable_tasks; @@ -721,7 +707,6 @@ struct dl_rq { u64 next; } earliest_dl; - unsigned int dl_nr_migratory; int overloaded; /* @@ -963,10 +948,6 @@ struct rq { /* runqueue lock: */ raw_spinlock_t __lock; - /* - * nr_running and cpu_load should be in the same cacheline because - * remote CPUs use both these fields when doing load calculation. - */ unsigned int nr_running; #ifdef CONFIG_NUMA_BALANCING unsigned int nr_numa_running; @@ -1048,7 +1029,6 @@ struct rq { struct sched_domain __rcu *sd; unsigned long cpu_capacity; - unsigned long cpu_capacity_orig; struct balance_callback *balance_callback; @@ -1079,9 +1059,6 @@ struct rq { u64 idle_stamp; u64 avg_idle; - unsigned long wake_stamp; - u64 wake_avg_idle; - /* This is used to determine avg_idle's max value */ u64 max_idle_balance_cost; @@ -1658,6 +1635,11 @@ task_rq_unlock(struct rq *rq, struct task_struct *p, struct rq_flags *rf) raw_spin_unlock_irqrestore(&p->pi_lock, rf->flags); } +DEFINE_LOCK_GUARD_1(task_rq_lock, struct task_struct, + _T->rq = task_rq_lock(_T->lock, &_T->rf), + task_rq_unlock(_T->rq, _T->lock, &_T->rf), + struct rq *rq; struct rq_flags rf) + static inline void rq_lock_irqsave(struct rq *rq, struct rq_flags *rf) __acquires(rq->lock) @@ -1868,11 +1850,13 @@ static inline struct sched_domain *lowest_flag_domain(int cpu, int flag) DECLARE_PER_CPU(struct sched_domain __rcu *, sd_llc); DECLARE_PER_CPU(int, sd_llc_size); DECLARE_PER_CPU(int, sd_llc_id); +DECLARE_PER_CPU(int, sd_share_id); DECLARE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); DECLARE_PER_CPU(struct sched_domain __rcu *, sd_numa); DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); DECLARE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); extern struct static_key_false sched_asym_cpucapacity; +extern struct static_key_false sched_cluster_active; static __always_inline bool sched_asym_cpucap_active(void) { @@ -2239,7 +2223,7 @@ struct sched_class { void (*yield_task) (struct rq *rq); bool (*yield_to_task)(struct rq *rq, struct task_struct *p); - void (*check_preempt_curr)(struct rq *rq, struct task_struct *p, int flags); + void (*wakeup_preempt)(struct rq *rq, struct task_struct *p, int flags); struct task_struct *(*pick_next_task)(struct rq *rq); @@ -2513,7 +2497,7 @@ static inline void sub_nr_running(struct rq *rq, unsigned count) extern void activate_task(struct rq *rq, struct task_struct *p, int flags); extern void deactivate_task(struct rq *rq, struct task_struct *p, int flags); -extern void check_preempt_curr(struct rq *rq, struct task_struct *p, int flags); +extern void wakeup_preempt(struct rq *rq, struct task_struct *p, int flags); #ifdef CONFIG_PREEMPT_RT #define SCHED_NR_MIGRATE_BREAK 8 @@ -2977,11 +2961,6 @@ static inline void cpufreq_update_util(struct rq *rq, unsigned int flags) {} #endif #ifdef CONFIG_SMP -static inline unsigned long capacity_orig_of(int cpu) -{ - return cpu_rq(cpu)->cpu_capacity_orig; -} - /** * enum cpu_util_type - CPU utilization type * @FREQUENCY_UTIL: Utilization used to select frequency @@ -3219,6 +3198,8 @@ static inline bool sched_energy_enabled(void) return static_branch_unlikely(&sched_energy_present); } +extern struct cpufreq_governor schedutil_gov; + #else /* ! (CONFIG_ENERGY_MODEL && CONFIG_CPU_FREQ_GOV_SCHEDUTIL) */ #define perf_domain_span(pd) NULL diff --git a/kernel/sched/stop_task.c b/kernel/sched/stop_task.c index 85590599b4..6cf7304e64 100644 --- a/kernel/sched/stop_task.c +++ b/kernel/sched/stop_task.c @@ -23,7 +23,7 @@ balance_stop(struct rq *rq, struct task_struct *prev, struct rq_flags *rf) #endif /* CONFIG_SMP */ static void -check_preempt_curr_stop(struct rq *rq, struct task_struct *p, int flags) +wakeup_preempt_stop(struct rq *rq, struct task_struct *p, int flags) { /* we're never preempted */ } @@ -120,7 +120,7 @@ DEFINE_SCHED_CLASS(stop) = { .dequeue_task = dequeue_task_stop, .yield_task = yield_task_stop, - .check_preempt_curr = check_preempt_curr_stop, + .wakeup_preempt = wakeup_preempt_stop, .pick_next_task = pick_next_task_stop, .put_prev_task = put_prev_task_stop, diff --git a/kernel/sched/topology.c b/kernel/sched/topology.c index 423d089479..10d1391e74 100644 --- a/kernel/sched/topology.c +++ b/kernel/sched/topology.c @@ -212,6 +212,69 @@ static unsigned int sysctl_sched_energy_aware = 1; static DEFINE_MUTEX(sched_energy_mutex); static bool sched_energy_update; +static bool sched_is_eas_possible(const struct cpumask *cpu_mask) +{ + bool any_asym_capacity = false; + struct cpufreq_policy *policy; + struct cpufreq_governor *gov; + int i; + + /* EAS is enabled for asymmetric CPU capacity topologies. */ + for_each_cpu(i, cpu_mask) { + if (rcu_access_pointer(per_cpu(sd_asym_cpucapacity, i))) { + any_asym_capacity = true; + break; + } + } + if (!any_asym_capacity) { + if (sched_debug()) { + pr_info("rd %*pbl: Checking EAS, CPUs do not have asymmetric capacities\n", + cpumask_pr_args(cpu_mask)); + } + return false; + } + + /* EAS definitely does *not* handle SMT */ + if (sched_smt_active()) { + if (sched_debug()) { + pr_info("rd %*pbl: Checking EAS, SMT is not supported\n", + cpumask_pr_args(cpu_mask)); + } + return false; + } + + if (!arch_scale_freq_invariant()) { + if (sched_debug()) { + pr_info("rd %*pbl: Checking EAS: frequency-invariant load tracking not yet supported", + cpumask_pr_args(cpu_mask)); + } + return false; + } + + /* Do not attempt EAS if schedutil is not being used. */ + for_each_cpu(i, cpu_mask) { + policy = cpufreq_cpu_get(i); + if (!policy) { + if (sched_debug()) { + pr_info("rd %*pbl: Checking EAS, cpufreq policy not set for CPU: %d", + cpumask_pr_args(cpu_mask), i); + } + return false; + } + gov = policy->governor; + cpufreq_cpu_put(policy); + if (gov != &schedutil_gov) { + if (sched_debug()) { + pr_info("rd %*pbl: Checking EAS, schedutil is mandatory\n", + cpumask_pr_args(cpu_mask)); + } + return false; + } + } + + return true; +} + void rebuild_sched_domains_energy(void) { mutex_lock(&sched_energy_mutex); @@ -230,6 +293,15 @@ static int sched_energy_aware_handler(struct ctl_table *table, int write, if (write && !capable(CAP_SYS_ADMIN)) return -EPERM; + if (!sched_is_eas_possible(cpu_active_mask)) { + if (write) { + return -EOPNOTSUPP; + } else { + *lenp = 0; + return 0; + } + } + ret = proc_dointvec_minmax(table, write, buffer, lenp, ppos); if (!ret && write) { state = static_branch_unlikely(&sched_energy_present); @@ -348,103 +420,33 @@ static void sched_energy_set(bool has_eas) * 1. an Energy Model (EM) is available; * 2. the SD_ASYM_CPUCAPACITY flag is set in the sched_domain hierarchy. * 3. no SMT is detected. - * 4. the EM complexity is low enough to keep scheduling overheads low; - * 5. schedutil is driving the frequency of all CPUs of the rd; - * 6. frequency invariance support is present; - * - * The complexity of the Energy Model is defined as: - * - * C = nr_pd * (nr_cpus + nr_ps) - * - * with parameters defined as: - * - nr_pd: the number of performance domains - * - nr_cpus: the number of CPUs - * - nr_ps: the sum of the number of performance states of all performance - * domains (for example, on a system with 2 performance domains, - * with 10 performance states each, nr_ps = 2 * 10 = 20). - * - * It is generally not a good idea to use such a model in the wake-up path on - * very complex platforms because of the associated scheduling overheads. The - * arbitrary constraint below prevents that. It makes EAS usable up to 16 CPUs - * with per-CPU DVFS and less than 8 performance states each, for example. + * 4. schedutil is driving the frequency of all CPUs of the rd; + * 5. frequency invariance support is present; */ -#define EM_MAX_COMPLEXITY 2048 - -extern struct cpufreq_governor schedutil_gov; static bool build_perf_domains(const struct cpumask *cpu_map) { - int i, nr_pd = 0, nr_ps = 0, nr_cpus = cpumask_weight(cpu_map); + int i; struct perf_domain *pd = NULL, *tmp; int cpu = cpumask_first(cpu_map); struct root_domain *rd = cpu_rq(cpu)->rd; - struct cpufreq_policy *policy; - struct cpufreq_governor *gov; if (!sysctl_sched_energy_aware) goto free; - /* EAS is enabled for asymmetric CPU capacity topologies. */ - if (!per_cpu(sd_asym_cpucapacity, cpu)) { - if (sched_debug()) { - pr_info("rd %*pbl: CPUs do not have asymmetric capacities\n", - cpumask_pr_args(cpu_map)); - } - goto free; - } - - /* EAS definitely does *not* handle SMT */ - if (sched_smt_active()) { - pr_warn("rd %*pbl: Disabling EAS, SMT is not supported\n", - cpumask_pr_args(cpu_map)); - goto free; - } - - if (!arch_scale_freq_invariant()) { - if (sched_debug()) { - pr_warn("rd %*pbl: Disabling EAS: frequency-invariant load tracking not yet supported", - cpumask_pr_args(cpu_map)); - } + if (!sched_is_eas_possible(cpu_map)) goto free; - } for_each_cpu(i, cpu_map) { /* Skip already covered CPUs. */ if (find_pd(pd, i)) continue; - /* Do not attempt EAS if schedutil is not being used. */ - policy = cpufreq_cpu_get(i); - if (!policy) - goto free; - gov = policy->governor; - cpufreq_cpu_put(policy); - if (gov != &schedutil_gov) { - if (rd->pd) - pr_warn("rd %*pbl: Disabling EAS, schedutil is mandatory\n", - cpumask_pr_args(cpu_map)); - goto free; - } - /* Create the new pd and add it to the local list. */ tmp = pd_init(i); if (!tmp) goto free; tmp->next = pd; pd = tmp; - - /* - * Count performance domains and performance states for the - * complexity check. - */ - nr_pd++; - nr_ps += em_pd_nr_perf_states(pd->em_pd); - } - - /* Bail out if the Energy Model complexity is too high. */ - if (nr_pd * (nr_ps + nr_cpus) > EM_MAX_COMPLEXITY) { - WARN(1, "rd %*pbl: Failed to start EAS, EM complexity is too high\n", - cpumask_pr_args(cpu_map)); - goto free; } perf_domain_debug(cpu_map, pd); @@ -666,11 +668,14 @@ static void destroy_sched_domains(struct sched_domain *sd) DEFINE_PER_CPU(struct sched_domain __rcu *, sd_llc); DEFINE_PER_CPU(int, sd_llc_size); DEFINE_PER_CPU(int, sd_llc_id); +DEFINE_PER_CPU(int, sd_share_id); DEFINE_PER_CPU(struct sched_domain_shared __rcu *, sd_llc_shared); DEFINE_PER_CPU(struct sched_domain __rcu *, sd_numa); DEFINE_PER_CPU(struct sched_domain __rcu *, sd_asym_packing); DEFINE_PER_CPU(struct sched_domain __rcu *, sd_asym_cpucapacity); + DEFINE_STATIC_KEY_FALSE(sched_asym_cpucapacity); +DEFINE_STATIC_KEY_FALSE(sched_cluster_active); static void update_top_cache_domain(int cpu) { @@ -691,6 +696,17 @@ static void update_top_cache_domain(int cpu) per_cpu(sd_llc_id, cpu) = id; rcu_assign_pointer(per_cpu(sd_llc_shared, cpu), sds); + sd = lowest_flag_domain(cpu, SD_CLUSTER); + if (sd) + id = cpumask_first(sched_domain_span(sd)); + + /* + * This assignment should be placed after the sd_llc_id as + * we want this id equals to cluster id on cluster machines + * but equals to LLC id on non-Cluster machines. + */ + per_cpu(sd_share_id, cpu) = id; + sd = lowest_flag_domain(cpu, SD_NUMA); rcu_assign_pointer(per_cpu(sd_numa, cpu), sd); @@ -1117,7 +1133,7 @@ fail: * * - Simultaneous multithreading (SMT) * - Multi-Core Cache (MC) - * - Package (DIE) + * - Package (PKG) * * Where the last one more or less denotes everything up to a NUMA node. * @@ -1139,13 +1155,13 @@ fail: * * CPU 0 1 2 3 4 5 6 7 * - * DIE [ ] + * PKG [ ] * MC [ ] [ ] * SMT [ ] [ ] [ ] [ ] * * - or - * - * DIE 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7 + * PKG 0-7 0-7 0-7 0-7 0-7 0-7 0-7 0-7 * MC 0-3 0-3 0-3 0-3 4-7 4-7 4-7 4-7 * SMT 0-1 0-1 2-3 2-3 4-5 4-5 6-7 6-7 * @@ -1548,6 +1564,7 @@ static struct cpumask ***sched_domains_numa_masks; */ #define TOPOLOGY_SD_FLAGS \ (SD_SHARE_CPUCAPACITY | \ + SD_CLUSTER | \ SD_SHARE_PKG_RESOURCES | \ SD_NUMA | \ SD_ASYM_PACKING) @@ -1679,7 +1696,7 @@ static struct sched_domain_topology_level default_topology[] = { #ifdef CONFIG_SCHED_MC { cpu_coregroup_mask, cpu_core_flags, SD_INIT_NAME(MC) }, #endif - { cpu_cpu_mask, SD_INIT_NAME(DIE) }, + { cpu_cpu_mask, SD_INIT_NAME(PKG) }, { NULL, }, }; @@ -2112,13 +2129,15 @@ static int hop_cmp(const void *a, const void *b) return -1; } -/* - * sched_numa_find_nth_cpu() - given the NUMA topology, find the Nth next cpu - * closest to @cpu from @cpumask. - * cpumask: cpumask to find a cpu from - * cpu: Nth cpu to find - * - * returns: cpu, or nr_cpu_ids when nothing found. +/** + * sched_numa_find_nth_cpu() - given the NUMA topology, find the Nth closest CPU + * from @cpus to @cpu, taking into account distance + * from a given @node. + * @cpus: cpumask to find a cpu from + * @cpu: CPU to start searching + * @node: NUMA node to order CPUs by distance + * + * Return: cpu, or nr_cpu_ids when nothing found. */ int sched_numa_find_nth_cpu(const struct cpumask *cpus, int cpu, int node) { @@ -2126,6 +2145,9 @@ int sched_numa_find_nth_cpu(const struct cpumask *cpus, int cpu, int node) struct cpumask ***hop_masks; int hop, ret = nr_cpu_ids; + if (node == NUMA_NO_NODE) + return cpumask_nth_and(cpu, cpus, cpu_online_mask); + rcu_read_lock(); /* CPU-less node entries are uninitialized in sched_domains_numa_masks */ @@ -2366,6 +2388,7 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att struct rq *rq = NULL; int i, ret = -ENOMEM; bool has_asym = false; + bool has_cluster = false; if (WARN_ON(cpumask_empty(cpu_map))) goto error; @@ -2483,20 +2506,29 @@ build_sched_domains(const struct cpumask *cpu_map, struct sched_domain_attr *att /* Attach the domains */ rcu_read_lock(); for_each_cpu(i, cpu_map) { + unsigned long capacity; + rq = cpu_rq(i); sd = *per_cpu_ptr(d.sd, i); + capacity = arch_scale_cpu_capacity(i); /* Use READ_ONCE()/WRITE_ONCE() to avoid load/store tearing: */ - if (rq->cpu_capacity_orig > READ_ONCE(d.rd->max_cpu_capacity)) - WRITE_ONCE(d.rd->max_cpu_capacity, rq->cpu_capacity_orig); + if (capacity > READ_ONCE(d.rd->max_cpu_capacity)) + WRITE_ONCE(d.rd->max_cpu_capacity, capacity); cpu_attach_domain(sd, d.rd, i); + + if (lowest_flag_domain(i, SD_CLUSTER)) + has_cluster = true; } rcu_read_unlock(); if (has_asym) static_branch_inc_cpuslocked(&sched_asym_cpucapacity); + if (has_cluster) + static_branch_inc_cpuslocked(&sched_cluster_active); + if (rq && sched_debug_verbose) { pr_info("root domain span: %*pbl (max cpu_capacity = %lu)\n", cpumask_pr_args(cpu_map), rq->rd->max_cpu_capacity); @@ -2596,6 +2628,9 @@ static void detach_destroy_domains(const struct cpumask *cpu_map) if (rcu_access_pointer(per_cpu(sd_asym_cpucapacity, cpu))) static_branch_dec_cpuslocked(&sched_asym_cpucapacity); + if (static_branch_unlikely(&sched_cluster_active)) + static_branch_dec_cpuslocked(&sched_cluster_active); + rcu_read_lock(); for_each_cpu(i, cpu_map) cpu_attach_domain(NULL, &def_root_domain, i); diff --git a/kernel/sched/wait.c b/kernel/sched/wait.c index 802d98cf2d..51e38f5f47 100644 --- a/kernel/sched/wait.c +++ b/kernel/sched/wait.c @@ -58,13 +58,6 @@ void remove_wait_queue(struct wait_queue_head *wq_head, struct wait_queue_entry EXPORT_SYMBOL(remove_wait_queue); /* - * Scan threshold to break wait queue walk. - * This allows a waker to take a break from holding the - * wait queue lock during the wait queue walk. - */ -#define WAITQUEUE_WALK_BREAK_CNT 64 - -/* * The core wakeup function. Non-exclusive wakeups (nr_exclusive == 0) just * wake everything up. If it's an exclusive wakeup (nr_exclusive == small +ve * number) then we wake that number of exclusive tasks, and potentially all @@ -78,21 +71,13 @@ EXPORT_SYMBOL(remove_wait_queue); * zero in this (rare) case, and we handle it by continuing to scan the queue. */ static int __wake_up_common(struct wait_queue_head *wq_head, unsigned int mode, - int nr_exclusive, int wake_flags, void *key, - wait_queue_entry_t *bookmark) + int nr_exclusive, int wake_flags, void *key) { wait_queue_entry_t *curr, *next; - int cnt = 0; lockdep_assert_held(&wq_head->lock); - if (bookmark && (bookmark->flags & WQ_FLAG_BOOKMARK)) { - curr = list_next_entry(bookmark, entry); - - list_del(&bookmark->entry); - bookmark->flags = 0; - } else - curr = list_first_entry(&wq_head->head, wait_queue_entry_t, entry); + curr = list_first_entry(&wq_head->head, wait_queue_entry_t, entry); if (&curr->entry == &wq_head->head) return nr_exclusive; @@ -101,21 +86,11 @@ static int __wake_up_common(struct wait_queue_head *wq_head, unsigned int mode, unsigned flags = curr->flags; int ret; - if (flags & WQ_FLAG_BOOKMARK) - continue; - ret = curr->func(curr, mode, wake_flags, key); if (ret < 0) break; if (ret && (flags & WQ_FLAG_EXCLUSIVE) && !--nr_exclusive) break; - - if (bookmark && (++cnt > WAITQUEUE_WALK_BREAK_CNT) && - (&next->entry != &wq_head->head)) { - bookmark->flags = WQ_FLAG_BOOKMARK; - list_add_tail(&bookmark->entry, &next->entry); - break; - } } return nr_exclusive; @@ -125,20 +100,12 @@ static int __wake_up_common_lock(struct wait_queue_head *wq_head, unsigned int m int nr_exclusive, int wake_flags, void *key) { unsigned long flags; - wait_queue_entry_t bookmark; - int remaining = nr_exclusive; + int remaining; - bookmark.flags = 0; - bookmark.private = NULL; - bookmark.func = NULL; - INIT_LIST_HEAD(&bookmark.entry); - - do { - spin_lock_irqsave(&wq_head->lock, flags); - remaining = __wake_up_common(wq_head, mode, remaining, - wake_flags, key, &bookmark); - spin_unlock_irqrestore(&wq_head->lock, flags); - } while (bookmark.flags & WQ_FLAG_BOOKMARK); + spin_lock_irqsave(&wq_head->lock, flags); + remaining = __wake_up_common(wq_head, mode, nr_exclusive, wake_flags, + key); + spin_unlock_irqrestore(&wq_head->lock, flags); return nr_exclusive - remaining; } @@ -171,23 +138,16 @@ void __wake_up_on_current_cpu(struct wait_queue_head *wq_head, unsigned int mode */ void __wake_up_locked(struct wait_queue_head *wq_head, unsigned int mode, int nr) { - __wake_up_common(wq_head, mode, nr, 0, NULL, NULL); + __wake_up_common(wq_head, mode, nr, 0, NULL); } EXPORT_SYMBOL_GPL(__wake_up_locked); void __wake_up_locked_key(struct wait_queue_head *wq_head, unsigned int mode, void *key) { - __wake_up_common(wq_head, mode, 1, 0, key, NULL); + __wake_up_common(wq_head, mode, 1, 0, key); } EXPORT_SYMBOL_GPL(__wake_up_locked_key); -void __wake_up_locked_key_bookmark(struct wait_queue_head *wq_head, - unsigned int mode, void *key, wait_queue_entry_t *bookmark) -{ - __wake_up_common(wq_head, mode, 1, 0, key, bookmark); -} -EXPORT_SYMBOL_GPL(__wake_up_locked_key_bookmark); - /** * __wake_up_sync_key - wake up threads blocked on a waitqueue. * @wq_head: the waitqueue @@ -233,7 +193,7 @@ EXPORT_SYMBOL_GPL(__wake_up_sync_key); void __wake_up_locked_sync_key(struct wait_queue_head *wq_head, unsigned int mode, void *key) { - __wake_up_common(wq_head, mode, 1, WF_SYNC, key, NULL); + __wake_up_common(wq_head, mode, 1, WF_SYNC, key); } EXPORT_SYMBOL_GPL(__wake_up_locked_sync_key); diff --git a/kernel/signal.c b/kernel/signal.c index 09019017d6..47a7602dfe 100644 --- a/kernel/signal.c +++ b/kernel/signal.c @@ -415,7 +415,7 @@ __sigqueue_alloc(int sig, struct task_struct *t, gfp_t gfp_flags, int override_rlimit, const unsigned int sigqueue_flags) { struct sigqueue *q = NULL; - struct ucounts *ucounts = NULL; + struct ucounts *ucounts; long sigpending; /* @@ -1058,12 +1058,11 @@ static void complete_signal(int sig, struct task_struct *p, enum pid_type type) signal->flags = SIGNAL_GROUP_EXIT; signal->group_exit_code = sig; signal->group_stop_count = 0; - t = p; - do { + __for_each_thread(signal, t) { task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK); sigaddset(&t->pending.signal, SIGKILL); signal_wake_up(t, 1); - } while_each_thread(p, t); + } return; } } @@ -1471,16 +1470,21 @@ int group_send_sig_info(int sig, struct kernel_siginfo *info, int __kill_pgrp_info(int sig, struct kernel_siginfo *info, struct pid *pgrp) { struct task_struct *p = NULL; - int retval, success; + int ret = -ESRCH; - success = 0; - retval = -ESRCH; do_each_pid_task(pgrp, PIDTYPE_PGID, p) { int err = group_send_sig_info(sig, info, p, PIDTYPE_PGID); - success |= !err; - retval = err; + /* + * If group_send_sig_info() succeeds at least once ret + * becomes 0 and after that the code below has no effect. + * Otherwise we return the last err or -ESRCH if this + * process group is empty. + */ + if (ret) + ret = err; } while_each_pid_task(pgrp, PIDTYPE_PGID, p); - return success ? 0 : retval; + + return ret; } int kill_pid_info(int sig, struct kernel_siginfo *info, struct pid *pid) @@ -1718,9 +1722,8 @@ void force_sigsegv(int sig) force_sig(SIGSEGV); } -int force_sig_fault_to_task(int sig, int code, void __user *addr - ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) - , struct task_struct *t) +int force_sig_fault_to_task(int sig, int code, void __user *addr, + struct task_struct *t) { struct kernel_siginfo info; @@ -1729,24 +1732,15 @@ int force_sig_fault_to_task(int sig, int code, void __user *addr info.si_errno = 0; info.si_code = code; info.si_addr = addr; -#ifdef __ia64__ - info.si_imm = imm; - info.si_flags = flags; - info.si_isr = isr; -#endif return force_sig_info_to_task(&info, t, HANDLER_CURRENT); } -int force_sig_fault(int sig, int code, void __user *addr - ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr)) +int force_sig_fault(int sig, int code, void __user *addr) { - return force_sig_fault_to_task(sig, code, addr - ___ARCH_SI_IA64(imm, flags, isr), current); + return force_sig_fault_to_task(sig, code, addr, current); } -int send_sig_fault(int sig, int code, void __user *addr - ___ARCH_SI_IA64(int imm, unsigned int flags, unsigned long isr) - , struct task_struct *t) +int send_sig_fault(int sig, int code, void __user *addr, struct task_struct *t) { struct kernel_siginfo info; @@ -1755,11 +1749,6 @@ int send_sig_fault(int sig, int code, void __user *addr info.si_errno = 0; info.si_code = code; info.si_addr = addr; -#ifdef __ia64__ - info.si_imm = imm; - info.si_flags = flags; - info.si_isr = isr; -#endif return send_sig_info(info.si_signo, &info, t); } @@ -2329,15 +2318,38 @@ static int ptrace_stop(int exit_code, int why, unsigned long message, do_notify_parent_cldstop(current, false, why); /* - * Don't want to allow preemption here, because - * sys_ptrace() needs this task to be inactive. + * The previous do_notify_parent_cldstop() invocation woke ptracer. + * One a PREEMPTION kernel this can result in preemption requirement + * which will be fulfilled after read_unlock() and the ptracer will be + * put on the CPU. + * The ptracer is in wait_task_inactive(, __TASK_TRACED) waiting for + * this task wait in schedule(). If this task gets preempted then it + * remains enqueued on the runqueue. The ptracer will observe this and + * then sleep for a delay of one HZ tick. In the meantime this task + * gets scheduled, enters schedule() and will wait for the ptracer. * - * XXX: implement read_unlock_no_resched(). + * This preemption point is not bad from a correctness point of + * view but extends the runtime by one HZ tick time due to the + * ptracer's sleep. The preempt-disable section ensures that there + * will be no preemption between unlock and schedule() and so + * improving the performance since the ptracer will observe that + * the tracee is scheduled out once it gets on the CPU. + * + * On PREEMPT_RT locking tasklist_lock does not disable preemption. + * Therefore the task can be preempted after do_notify_parent_cldstop() + * before unlocking tasklist_lock so there is no benefit in doing this. + * + * In fact disabling preemption is harmful on PREEMPT_RT because + * the spinlock_t in cgroup_enter_frozen() must not be acquired + * with preemption disabled due to the 'sleeping' spinlock + * substitution of RT. */ - preempt_disable(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_disable(); read_unlock(&tasklist_lock); cgroup_enter_frozen(); - preempt_enable_no_resched(); + if (!IS_ENABLED(CONFIG_PREEMPT_RT)) + preempt_enable_no_resched(); schedule(); cgroup_leave_frozen(true); diff --git a/kernel/smp.c b/kernel/smp.c index 695eb13a27..f085ebcdf9 100644 --- a/kernel/smp.c +++ b/kernel/smp.c @@ -127,7 +127,7 @@ send_call_function_ipi_mask(struct cpumask *mask) } static __always_inline void -csd_do_func(smp_call_func_t func, void *info, struct __call_single_data *csd) +csd_do_func(smp_call_func_t func, void *info, call_single_data_t *csd) { trace_csd_function_entry(func, csd); func(info); @@ -176,7 +176,7 @@ module_param(panic_on_ipistall, int, 0444); static atomic_t csd_bug_count = ATOMIC_INIT(0); /* Record current CSD work for current CPU, NULL to erase. */ -static void __csd_lock_record(struct __call_single_data *csd) +static void __csd_lock_record(call_single_data_t *csd) { if (!csd) { smp_mb(); /* NULL cur_csd after unlock. */ @@ -191,13 +191,13 @@ static void __csd_lock_record(struct __call_single_data *csd) /* Or before unlock, as the case may be. */ } -static __always_inline void csd_lock_record(struct __call_single_data *csd) +static __always_inline void csd_lock_record(call_single_data_t *csd) { if (static_branch_unlikely(&csdlock_debug_enabled)) __csd_lock_record(csd); } -static int csd_lock_wait_getcpu(struct __call_single_data *csd) +static int csd_lock_wait_getcpu(call_single_data_t *csd) { unsigned int csd_type; @@ -212,7 +212,7 @@ static int csd_lock_wait_getcpu(struct __call_single_data *csd) * the CSD_TYPE_SYNC/ASYNC types provide the destination CPU, * so waiting on other types gets much less information. */ -static bool csd_lock_wait_toolong(struct __call_single_data *csd, u64 ts0, u64 *ts1, int *bug_id) +static bool csd_lock_wait_toolong(call_single_data_t *csd, u64 ts0, u64 *ts1, int *bug_id) { int cpu = -1; int cpux; @@ -287,7 +287,7 @@ static bool csd_lock_wait_toolong(struct __call_single_data *csd, u64 ts0, u64 * * previous function call. For multi-cpu calls its even more interesting * as we'll have to ensure no other cpu is observing our csd. */ -static void __csd_lock_wait(struct __call_single_data *csd) +static void __csd_lock_wait(call_single_data_t *csd) { int bug_id = 0; u64 ts0, ts1; @@ -301,7 +301,7 @@ static void __csd_lock_wait(struct __call_single_data *csd) smp_acquire__after_ctrl_dep(); } -static __always_inline void csd_lock_wait(struct __call_single_data *csd) +static __always_inline void csd_lock_wait(call_single_data_t *csd) { if (static_branch_unlikely(&csdlock_debug_enabled)) { __csd_lock_wait(csd); @@ -311,17 +311,17 @@ static __always_inline void csd_lock_wait(struct __call_single_data *csd) smp_cond_load_acquire(&csd->node.u_flags, !(VAL & CSD_FLAG_LOCK)); } #else -static void csd_lock_record(struct __call_single_data *csd) +static void csd_lock_record(call_single_data_t *csd) { } -static __always_inline void csd_lock_wait(struct __call_single_data *csd) +static __always_inline void csd_lock_wait(call_single_data_t *csd) { smp_cond_load_acquire(&csd->node.u_flags, !(VAL & CSD_FLAG_LOCK)); } #endif -static __always_inline void csd_lock(struct __call_single_data *csd) +static __always_inline void csd_lock(call_single_data_t *csd) { csd_lock_wait(csd); csd->node.u_flags |= CSD_FLAG_LOCK; @@ -334,7 +334,7 @@ static __always_inline void csd_lock(struct __call_single_data *csd) smp_wmb(); } -static __always_inline void csd_unlock(struct __call_single_data *csd) +static __always_inline void csd_unlock(call_single_data_t *csd) { WARN_ON(!(csd->node.u_flags & CSD_FLAG_LOCK)); @@ -387,7 +387,7 @@ void __smp_call_single_queue(int cpu, struct llist_node *node) * for execution on the given CPU. data must already have * ->func, ->info, and ->flags set. */ -static int generic_exec_single(int cpu, struct __call_single_data *csd) +static int generic_exec_single(int cpu, call_single_data_t *csd) { if (cpu == smp_processor_id()) { smp_call_func_t func = csd->func; @@ -678,7 +678,7 @@ EXPORT_SYMBOL(smp_call_function_single); * * Return: %0 on success or negative errno value on error */ -int smp_call_function_single_async(int cpu, struct __call_single_data *csd) +int smp_call_function_single_async(int cpu, call_single_data_t *csd) { int err = 0; diff --git a/kernel/smpboot.c b/kernel/smpboot.c index f47d8f3759..1992b62e98 100644 --- a/kernel/smpboot.c +++ b/kernel/smpboot.c @@ -272,8 +272,7 @@ static void smpboot_destroy_threads(struct smp_hotplug_thread *ht) struct task_struct *tsk = *per_cpu_ptr(ht->store, cpu); if (tsk) { - kthread_stop(tsk); - put_task_struct(tsk); + kthread_stop_put(tsk); *per_cpu_ptr(ht->store, cpu) = NULL; } } diff --git a/kernel/stacktrace.c b/kernel/stacktrace.c index 9ed5ce9894..4f65824879 100644 --- a/kernel/stacktrace.c +++ b/kernel/stacktrace.c @@ -151,6 +151,7 @@ unsigned int stack_trace_save_tsk(struct task_struct *tsk, unsigned long *store, put_task_stack(tsk); return c.len; } +EXPORT_SYMBOL_GPL(stack_trace_save_tsk); /** * stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array @@ -301,6 +302,7 @@ unsigned int stack_trace_save_tsk(struct task_struct *task, save_stack_trace_tsk(task, &trace); return trace.nr_entries; } +EXPORT_SYMBOL_GPL(stack_trace_save_tsk); /** * stack_trace_save_regs - Save a stack trace based on pt_regs into a storage array diff --git a/kernel/sys.c b/kernel/sys.c index 7a4ae6d5ae..f8e543f1e3 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -1785,74 +1785,87 @@ void getrusage(struct task_struct *p, int who, struct rusage *r) struct task_struct *t; unsigned long flags; u64 tgutime, tgstime, utime, stime; - unsigned long maxrss = 0; + unsigned long maxrss; + struct mm_struct *mm; + struct signal_struct *sig = p->signal; + unsigned int seq = 0; - memset((char *)r, 0, sizeof (*r)); +retry: + memset(r, 0, sizeof(*r)); utime = stime = 0; + maxrss = 0; if (who == RUSAGE_THREAD) { task_cputime_adjusted(current, &utime, &stime); accumulate_thread_rusage(p, r); - maxrss = p->signal->maxrss; - goto out; + maxrss = sig->maxrss; + goto out_thread; } - if (!lock_task_sighand(p, &flags)) - return; + flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq); switch (who) { case RUSAGE_BOTH: case RUSAGE_CHILDREN: - utime = p->signal->cutime; - stime = p->signal->cstime; - r->ru_nvcsw = p->signal->cnvcsw; - r->ru_nivcsw = p->signal->cnivcsw; - r->ru_minflt = p->signal->cmin_flt; - r->ru_majflt = p->signal->cmaj_flt; - r->ru_inblock = p->signal->cinblock; - r->ru_oublock = p->signal->coublock; - maxrss = p->signal->cmaxrss; + utime = sig->cutime; + stime = sig->cstime; + r->ru_nvcsw = sig->cnvcsw; + r->ru_nivcsw = sig->cnivcsw; + r->ru_minflt = sig->cmin_flt; + r->ru_majflt = sig->cmaj_flt; + r->ru_inblock = sig->cinblock; + r->ru_oublock = sig->coublock; + maxrss = sig->cmaxrss; if (who == RUSAGE_CHILDREN) break; fallthrough; case RUSAGE_SELF: - thread_group_cputime_adjusted(p, &tgutime, &tgstime); - utime += tgutime; - stime += tgstime; - r->ru_nvcsw += p->signal->nvcsw; - r->ru_nivcsw += p->signal->nivcsw; - r->ru_minflt += p->signal->min_flt; - r->ru_majflt += p->signal->maj_flt; - r->ru_inblock += p->signal->inblock; - r->ru_oublock += p->signal->oublock; - if (maxrss < p->signal->maxrss) - maxrss = p->signal->maxrss; - t = p; - do { + r->ru_nvcsw += sig->nvcsw; + r->ru_nivcsw += sig->nivcsw; + r->ru_minflt += sig->min_flt; + r->ru_majflt += sig->maj_flt; + r->ru_inblock += sig->inblock; + r->ru_oublock += sig->oublock; + if (maxrss < sig->maxrss) + maxrss = sig->maxrss; + + rcu_read_lock(); + __for_each_thread(sig, t) accumulate_thread_rusage(t, r); - } while_each_thread(p, t); + rcu_read_unlock(); + break; default: BUG(); } - unlock_task_sighand(p, &flags); -out: - r->ru_utime = ns_to_kernel_old_timeval(utime); - r->ru_stime = ns_to_kernel_old_timeval(stime); + if (need_seqretry(&sig->stats_lock, seq)) { + seq = 1; + goto retry; + } + done_seqretry_irqrestore(&sig->stats_lock, seq, flags); - if (who != RUSAGE_CHILDREN) { - struct mm_struct *mm = get_task_mm(p); + if (who == RUSAGE_CHILDREN) + goto out_children; - if (mm) { - setmax_mm_hiwater_rss(&maxrss, mm); - mmput(mm); - } + thread_group_cputime_adjusted(p, &tgutime, &tgstime); + utime += tgutime; + stime += tgstime; + +out_thread: + mm = get_task_mm(p); + if (mm) { + setmax_mm_hiwater_rss(&maxrss, mm); + mmput(mm); } + +out_children: r->ru_maxrss = maxrss * (PAGE_SIZE / 1024); /* convert pages to KBs */ + r->ru_utime = ns_to_kernel_old_timeval(utime); + r->ru_stime = ns_to_kernel_old_timeval(stime); } SYSCALL_DEFINE2(getrusage, int, who, struct rusage __user *, ru) diff --git a/kernel/sys_ni.c b/kernel/sys_ni.c index 11c55593a2..9a846439b3 100644 --- a/kernel/sys_ni.c +++ b/kernel/sys_ni.c @@ -51,8 +51,6 @@ COND_SYSCALL_COMPAT(io_pgetevents); COND_SYSCALL(io_uring_setup); COND_SYSCALL(io_uring_enter); COND_SYSCALL(io_uring_register); -COND_SYSCALL(lookup_dcookie); -COND_SYSCALL_COMPAT(lookup_dcookie); COND_SYSCALL(eventfd2); COND_SYSCALL(epoll_create1); COND_SYSCALL(epoll_ctl); @@ -87,6 +85,9 @@ COND_SYSCALL_COMPAT(set_robust_list); COND_SYSCALL(get_robust_list); COND_SYSCALL_COMPAT(get_robust_list); COND_SYSCALL(futex_waitv); +COND_SYSCALL(futex_wake); +COND_SYSCALL(futex_wait); +COND_SYSCALL(futex_requeue); COND_SYSCALL(kexec_load); COND_SYSCALL_COMPAT(kexec_load); COND_SYSCALL(init_module); diff --git a/kernel/sysctl.c b/kernel/sysctl.c index 354a2d294f..157f7ce294 100644 --- a/kernel/sysctl.c +++ b/kernel/sysctl.c @@ -1939,15 +1939,6 @@ static struct ctl_table kern_table[] = { .proc_handler = proc_dointvec, }, #endif -#ifdef CONFIG_IA64 - { - .procname = "unaligned-dump-stack", - .data = &unaligned_dump_stack, - .maxlen = sizeof (int), - .mode = 0644, - .proc_handler = proc_dointvec, - }, -#endif #ifdef CONFIG_RT_MUTEXES { .procname = "max_lock_depth", @@ -1983,7 +1974,7 @@ static struct ctl_table kern_table[] = { .data = &sysctl_perf_event_sample_rate, .maxlen = sizeof(sysctl_perf_event_sample_rate), .mode = 0644, - .proc_handler = perf_proc_update_handler, + .proc_handler = perf_event_max_sample_rate_handler, .extra1 = SYSCTL_ONE, }, { diff --git a/kernel/taskstats.c b/kernel/taskstats.c index 8ce3fa0c19..4354ea231f 100644 --- a/kernel/taskstats.c +++ b/kernel/taskstats.c @@ -233,9 +233,8 @@ static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) else memset(stats, 0, sizeof(*stats)); - tsk = first; start_time = ktime_get_ns(); - do { + for_each_thread(first, tsk) { if (tsk->exit_state) continue; /* @@ -258,7 +257,7 @@ static int fill_stats_for_tgid(pid_t tgid, struct taskstats *stats) stats->nvcsw += tsk->nvcsw; stats->nivcsw += tsk->nivcsw; - } while_each_thread(first, tsk); + } unlock_task_sighand(first, &flags); rc = 0; diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c index 8d9f13d847..4657cb8e8b 100644 --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -290,6 +290,17 @@ static int alarmtimer_suspend(struct device *dev) rtc_timer_cancel(rtc, &rtctimer); rtc_read_time(rtc, &tm); now = rtc_tm_to_ktime(tm); + + /* + * If the RTC alarm timer only supports a limited time offset, set the + * alarm time to the maximum supported value. + * The system may wake up earlier (possibly much earlier) than expected + * when the alarmtimer runs. This is the best the kernel can do if + * the alarmtimer exceeds the time that the rtc device can be programmed + * for. + */ + min = rtc_bound_alarmtime(rtc, min); + now = ktime_add(now, min); /* Set alarm, if in the past reject suspend briefly to handle */ diff --git a/kernel/time/hrtimer.c b/kernel/time/hrtimer.c index 760793998c..edb0f821dc 100644 --- a/kernel/time/hrtimer.c +++ b/kernel/time/hrtimer.c @@ -1085,6 +1085,7 @@ static int enqueue_hrtimer(struct hrtimer *timer, enum hrtimer_mode mode) { debug_activate(timer, mode); + WARN_ON_ONCE(!base->cpu_base->online); base->cpu_base->active_bases |= 1 << base->index; @@ -2183,6 +2184,7 @@ int hrtimers_prepare_cpu(unsigned int cpu) cpu_base->softirq_next_timer = NULL; cpu_base->expires_next = KTIME_MAX; cpu_base->softirq_expires_next = KTIME_MAX; + cpu_base->online = 1; hrtimer_cpu_base_init_expiry_lock(cpu_base); return 0; } @@ -2250,6 +2252,7 @@ int hrtimers_cpu_dying(unsigned int dying_cpu) smp_call_function_single(ncpu, retrigger_next_event, NULL, 0); raw_spin_unlock(&new_base->lock); + old_base->online = 0; raw_spin_unlock(&old_base->lock); return 0; diff --git a/kernel/time/posix-clock.c b/kernel/time/posix-clock.c index 77c0c2370b..9de66bbbb3 100644 --- a/kernel/time/posix-clock.c +++ b/kernel/time/posix-clock.c @@ -19,7 +19,8 @@ */ static struct posix_clock *get_posix_clock(struct file *fp) { - struct posix_clock *clk = fp->private_data; + struct posix_clock_context *pccontext = fp->private_data; + struct posix_clock *clk = pccontext->clk; down_read(&clk->rwsem); @@ -39,6 +40,7 @@ static void put_posix_clock(struct posix_clock *clk) static ssize_t posix_clock_read(struct file *fp, char __user *buf, size_t count, loff_t *ppos) { + struct posix_clock_context *pccontext = fp->private_data; struct posix_clock *clk = get_posix_clock(fp); int err = -EINVAL; @@ -46,7 +48,7 @@ static ssize_t posix_clock_read(struct file *fp, char __user *buf, return -ENODEV; if (clk->ops.read) - err = clk->ops.read(clk, fp->f_flags, buf, count); + err = clk->ops.read(pccontext, fp->f_flags, buf, count); put_posix_clock(clk); @@ -55,6 +57,7 @@ static ssize_t posix_clock_read(struct file *fp, char __user *buf, static __poll_t posix_clock_poll(struct file *fp, poll_table *wait) { + struct posix_clock_context *pccontext = fp->private_data; struct posix_clock *clk = get_posix_clock(fp); __poll_t result = 0; @@ -62,7 +65,7 @@ static __poll_t posix_clock_poll(struct file *fp, poll_table *wait) return EPOLLERR; if (clk->ops.poll) - result = clk->ops.poll(clk, fp, wait); + result = clk->ops.poll(pccontext, fp, wait); put_posix_clock(clk); @@ -72,6 +75,7 @@ static __poll_t posix_clock_poll(struct file *fp, poll_table *wait) static long posix_clock_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) { + struct posix_clock_context *pccontext = fp->private_data; struct posix_clock *clk = get_posix_clock(fp); int err = -ENOTTY; @@ -79,7 +83,7 @@ static long posix_clock_ioctl(struct file *fp, return -ENODEV; if (clk->ops.ioctl) - err = clk->ops.ioctl(clk, cmd, arg); + err = clk->ops.ioctl(pccontext, cmd, arg); put_posix_clock(clk); @@ -90,6 +94,7 @@ static long posix_clock_ioctl(struct file *fp, static long posix_clock_compat_ioctl(struct file *fp, unsigned int cmd, unsigned long arg) { + struct posix_clock_context *pccontext = fp->private_data; struct posix_clock *clk = get_posix_clock(fp); int err = -ENOTTY; @@ -97,7 +102,7 @@ static long posix_clock_compat_ioctl(struct file *fp, return -ENODEV; if (clk->ops.ioctl) - err = clk->ops.ioctl(clk, cmd, arg); + err = clk->ops.ioctl(pccontext, cmd, arg); put_posix_clock(clk); @@ -110,6 +115,7 @@ static int posix_clock_open(struct inode *inode, struct file *fp) int err; struct posix_clock *clk = container_of(inode->i_cdev, struct posix_clock, cdev); + struct posix_clock_context *pccontext; down_read(&clk->rwsem); @@ -117,14 +123,20 @@ static int posix_clock_open(struct inode *inode, struct file *fp) err = -ENODEV; goto out; } + pccontext = kzalloc(sizeof(*pccontext), GFP_KERNEL); + if (!pccontext) { + err = -ENOMEM; + goto out; + } + pccontext->clk = clk; + fp->private_data = pccontext; if (clk->ops.open) - err = clk->ops.open(clk, fp->f_mode); + err = clk->ops.open(pccontext, fp->f_mode); else err = 0; if (!err) { get_device(clk->dev); - fp->private_data = clk; } out: up_read(&clk->rwsem); @@ -133,14 +145,20 @@ out: static int posix_clock_release(struct inode *inode, struct file *fp) { - struct posix_clock *clk = fp->private_data; + struct posix_clock_context *pccontext = fp->private_data; + struct posix_clock *clk; int err = 0; + if (!pccontext) + return -ENODEV; + clk = pccontext->clk; + if (clk->ops.release) - err = clk->ops.release(clk); + err = clk->ops.release(pccontext); put_device(clk->dev); + kfree(pccontext); fp->private_data = NULL; return err; diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index 55cbc49f70..ca2d59579f 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -4,7 +4,7 @@ * Copyright(C) 2005-2007, Red Hat, Inc., Ingo Molnar * Copyright(C) 2006-2007 Timesys Corp., Thomas Gleixner * - * No idle tick implementation for low and high resolution timers + * NOHZ implementation for low and high resolution timers * * Started by: Thomas Gleixner and Ingo Molnar */ @@ -45,7 +45,7 @@ struct tick_sched *tick_get_tick_sched(int cpu) #if defined(CONFIG_NO_HZ_COMMON) || defined(CONFIG_HIGH_RES_TIMERS) /* - * The time, when the last jiffy update happened. Write access must hold + * The time when the last jiffy update happened. Write access must hold * jiffies_lock and jiffies_seq. tick_nohz_next_event() needs to get a * consistent view of jiffies and last_jiffies_update. */ @@ -60,13 +60,13 @@ static void tick_do_update_jiffies64(ktime_t now) ktime_t delta, nextp; /* - * 64bit can do a quick check without holding jiffies lock and + * 64-bit can do a quick check without holding the jiffies lock and * without looking at the sequence count. The smp_load_acquire() * pairs with the update done later in this function. * - * 32bit cannot do that because the store of tick_next_period - * consists of two 32bit stores and the first store could move it - * to a random point in the future. + * 32-bit cannot do that because the store of 'tick_next_period' + * consists of two 32-bit stores, and the first store could be + * moved by the CPU to a random point in the future. */ if (IS_ENABLED(CONFIG_64BIT)) { if (ktime_before(now, smp_load_acquire(&tick_next_period))) @@ -75,7 +75,7 @@ static void tick_do_update_jiffies64(ktime_t now) unsigned int seq; /* - * Avoid contention on jiffies_lock and protect the quick + * Avoid contention on 'jiffies_lock' and protect the quick * check with the sequence count. */ do { @@ -90,7 +90,7 @@ static void tick_do_update_jiffies64(ktime_t now) /* Quick check failed, i.e. update is required. */ raw_spin_lock(&jiffies_lock); /* - * Reevaluate with the lock held. Another CPU might have done the + * Re-evaluate with the lock held. Another CPU might have done the * update already. */ if (ktime_before(now, tick_next_period)) { @@ -114,25 +114,23 @@ static void tick_do_update_jiffies64(ktime_t now) TICK_NSEC); } - /* Advance jiffies to complete the jiffies_seq protected job */ + /* Advance jiffies to complete the 'jiffies_seq' protected job */ jiffies_64 += ticks; - /* - * Keep the tick_next_period variable up to date. - */ + /* Keep the tick_next_period variable up to date */ nextp = ktime_add_ns(last_jiffies_update, TICK_NSEC); if (IS_ENABLED(CONFIG_64BIT)) { /* * Pairs with smp_load_acquire() in the lockless quick - * check above and ensures that the update to jiffies_64 is - * not reordered vs. the store to tick_next_period, neither + * check above, and ensures that the update to 'jiffies_64' is + * not reordered vs. the store to 'tick_next_period', neither * by the compiler nor by the CPU. */ smp_store_release(&tick_next_period, nextp); } else { /* - * A plain store is good enough on 32bit as the quick check + * A plain store is good enough on 32-bit, as the quick check * above is protected by the sequence count. */ tick_next_period = nextp; @@ -140,7 +138,7 @@ static void tick_do_update_jiffies64(ktime_t now) /* * Release the sequence count. calc_global_load() below is not - * protected by it, but jiffies_lock needs to be held to prevent + * protected by it, but 'jiffies_lock' needs to be held to prevent * concurrent invocations. */ write_seqcount_end(&jiffies_seq); @@ -160,7 +158,8 @@ static ktime_t tick_init_jiffy_update(void) raw_spin_lock(&jiffies_lock); write_seqcount_begin(&jiffies_seq); - /* Did we start the jiffies update yet ? */ + + /* Have we started the jiffies update yet ? */ if (last_jiffies_update == 0) { u32 rem; @@ -175,8 +174,10 @@ static ktime_t tick_init_jiffy_update(void) last_jiffies_update = tick_next_period; } period = last_jiffies_update; + write_seqcount_end(&jiffies_seq); raw_spin_unlock(&jiffies_lock); + return period; } @@ -192,10 +193,10 @@ static void tick_sched_do_timer(struct tick_sched *ts, ktime_t now) * concurrency: This happens only when the CPU in charge went * into a long sleep. If two CPUs happen to assign themselves to * this duty, then the jiffies update is still serialized by - * jiffies_lock. + * 'jiffies_lock'. * * If nohz_full is enabled, this should not happen because the - * tick_do_timer_cpu never relinquishes. + * 'tick_do_timer_cpu' CPU never relinquishes. */ if (unlikely(tick_do_timer_cpu == TICK_DO_TIMER_NONE)) { #ifdef CONFIG_NO_HZ_FULL @@ -205,12 +206,12 @@ static void tick_sched_do_timer(struct tick_sched *ts, ktime_t now) } #endif - /* Check, if the jiffies need an update */ + /* Check if jiffies need an update */ if (tick_do_timer_cpu == cpu) tick_do_update_jiffies64(now); /* - * If jiffies update stalled for too long (timekeeper in stop_machine() + * If the jiffies update stalled for too long (timekeeper in stop_machine() * or VMEXIT'ed for several msecs), force an update. */ if (ts->last_tick_jiffies != jiffies) { @@ -234,10 +235,10 @@ static void tick_sched_handle(struct tick_sched *ts, struct pt_regs *regs) /* * When we are idle and the tick is stopped, we have to touch * the watchdog as we might not schedule for a really long - * time. This happens on complete idle SMP systems while + * time. This happens on completely idle SMP systems while * waiting on the login prompt. We also increment the "start of * idle" jiffy stamp so the idle accounting adjustment we do - * when we go busy again does not account too much ticks. + * when we go busy again does not account too many ticks. */ if (ts->tick_stopped) { touch_softlockup_watchdog_sched(); @@ -362,7 +363,7 @@ static void tick_nohz_kick_task(struct task_struct *tsk) /* * If the task is not running, run_posix_cpu_timers() - * has nothing to elapse, IPI can then be spared. + * has nothing to elapse, and an IPI can then be optimized out. * * activate_task() STORE p->tick_dep_mask * STORE p->on_rq @@ -425,7 +426,7 @@ static void tick_nohz_dep_set_all(atomic_t *dep, /* * Set a global tick dependency. Used by perf events that rely on freq and - * by unstable clock. + * unstable clocks. */ void tick_nohz_dep_set(enum tick_dep_bits bit) { @@ -439,7 +440,7 @@ void tick_nohz_dep_clear(enum tick_dep_bits bit) /* * Set per-CPU tick dependency. Used by scheduler and perf events in order to - * manage events throttling. + * manage event-throttling. */ void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) { @@ -455,7 +456,7 @@ void tick_nohz_dep_set_cpu(int cpu, enum tick_dep_bits bit) if (cpu == smp_processor_id()) { tick_nohz_full_kick(); } else { - /* Remote irq work not NMI-safe */ + /* Remote IRQ work not NMI-safe */ if (!WARN_ON_ONCE(in_nmi())) tick_nohz_full_kick_cpu(cpu); } @@ -473,7 +474,7 @@ void tick_nohz_dep_clear_cpu(int cpu, enum tick_dep_bits bit) EXPORT_SYMBOL_GPL(tick_nohz_dep_clear_cpu); /* - * Set a per-task tick dependency. RCU need this. Also posix CPU timers + * Set a per-task tick dependency. RCU needs this. Also posix CPU timers * in order to elapse per task timers. */ void tick_nohz_dep_set_task(struct task_struct *tsk, enum tick_dep_bits bit) @@ -546,7 +547,7 @@ void __init tick_nohz_full_setup(cpumask_var_t cpumask) bool tick_nohz_cpu_hotpluggable(unsigned int cpu) { /* - * The tick_do_timer_cpu CPU handles housekeeping duty (unbound + * The 'tick_do_timer_cpu' CPU handles housekeeping duty (unbound * timers, workqueues, timekeeping, ...) on behalf of full dynticks * CPUs. It must remain online when nohz full is enabled. */ @@ -568,12 +569,12 @@ void __init tick_nohz_init(void) return; /* - * Full dynticks uses irq work to drive the tick rescheduling on safe - * locking contexts. But then we need irq work to raise its own - * interrupts to avoid circular dependency on the tick + * Full dynticks uses IRQ work to drive the tick rescheduling on safe + * locking contexts. But then we need IRQ work to raise its own + * interrupts to avoid circular dependency on the tick. */ if (!arch_irq_work_has_interrupt()) { - pr_warn("NO_HZ: Can't run full dynticks because arch doesn't support irq work self-IPIs\n"); + pr_warn("NO_HZ: Can't run full dynticks because arch doesn't support IRQ work self-IPIs\n"); cpumask_clear(tick_nohz_full_mask); tick_nohz_full_running = false; return; @@ -643,7 +644,7 @@ bool tick_nohz_tick_stopped_cpu(int cpu) * In case the sched_tick was stopped on this CPU, we have to check if jiffies * must be updated. Otherwise an interrupt handler could use a stale jiffy * value. We do this unconditionally on any CPU, as we don't know whether the - * CPU, which has the update task assigned is in a long sleep. + * CPU, which has the update task assigned, is in a long sleep. */ static void tick_nohz_update_jiffies(ktime_t now) { @@ -726,7 +727,7 @@ static u64 get_cpu_sleep_time_us(struct tick_sched *ts, ktime_t *sleeptime, * counters if NULL. * * Return the cumulative idle time (since boot) for a given - * CPU, in microseconds. Note this is partially broken due to + * CPU, in microseconds. Note that this is partially broken due to * the counter of iowait tasks that can be remotely updated without * any synchronization. Therefore it is possible to observe backward * values within two consecutive reads. @@ -787,7 +788,7 @@ static void tick_nohz_restart(struct tick_sched *ts, ktime_t now) } /* - * Reset to make sure next tick stop doesn't get fooled by past + * Reset to make sure the next tick stop doesn't get fooled by past * cached clock deadline. */ ts->next_tick = 0; @@ -816,11 +817,11 @@ static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu) /* * Keep the periodic tick, when RCU, architecture or irq_work * requests it. - * Aside of that check whether the local timer softirq is - * pending. If so its a bad idea to call get_next_timer_interrupt() + * Aside of that, check whether the local timer softirq is + * pending. If so, its a bad idea to call get_next_timer_interrupt(), * because there is an already expired timer, so it will request * immediate expiry, which rearms the hardware timer with a - * minimal delta which brings us back to this place + * minimal delta, which brings us back to this place * immediately. Lather, rinse and repeat... */ if (rcu_needs_cpu() || arch_needs_cpu() || @@ -861,7 +862,7 @@ static ktime_t tick_nohz_next_event(struct tick_sched *ts, int cpu) /* * If this CPU is the one which had the do_timer() duty last, we limit - * the sleep time to the timekeeping max_deferment value. + * the sleep time to the timekeeping 'max_deferment' value. * Otherwise we can sleep as long as we want. */ delta = timekeeping_max_deferment(); @@ -895,8 +896,8 @@ static void tick_nohz_stop_tick(struct tick_sched *ts, int cpu) * If this CPU is the one which updates jiffies, then give up * the assignment and let it be taken by the CPU which runs * the tick timer next, which might be this CPU as well. If we - * don't drop this here the jiffies might be stale and - * do_timer() never invoked. Keep track of the fact that it + * don't drop this here, the jiffies might be stale and + * do_timer() never gets invoked. Keep track of the fact that it * was the one which had the do_timer() duty last. */ if (cpu == tick_do_timer_cpu) { @@ -906,7 +907,7 @@ static void tick_nohz_stop_tick(struct tick_sched *ts, int cpu) ts->do_timer_last = 0; } - /* Skip reprogram of event if its not changed */ + /* Skip reprogram of event if it's not changed */ if (ts->tick_stopped && (expires == ts->next_tick)) { /* Sanity check: make sure clockevent is actually programmed */ if (tick == KTIME_MAX || ts->next_tick == hrtimer_get_expires(&ts->sched_timer)) @@ -919,11 +920,11 @@ static void tick_nohz_stop_tick(struct tick_sched *ts, int cpu) } /* - * nohz_stop_sched_tick can be called several times before - * the nohz_restart_sched_tick is called. This happens when + * nohz_stop_sched_tick() can be called several times before + * nohz_restart_sched_tick() is called. This happens when * interrupts arrive which do not cause a reschedule. In the * first call we save the current tick time, so we can restart - * the scheduler tick in nohz_restart_sched_tick. + * the scheduler tick in nohz_restart_sched_tick(). */ if (!ts->tick_stopped) { calc_load_nohz_start(); @@ -985,9 +986,8 @@ static void tick_nohz_restart_sched_tick(struct tick_sched *ts, ktime_t now) calc_load_nohz_stop(); touch_softlockup_watchdog_sched(); - /* - * Cancel the scheduled timer and restore the tick - */ + + /* Cancel the scheduled timer and restore the tick: */ ts->tick_stopped = 0; tick_nohz_restart(ts, now); } @@ -1019,11 +1019,11 @@ static void tick_nohz_full_update_tick(struct tick_sched *ts) /* * A pending softirq outside an IRQ (or softirq disabled section) context * should be waiting for ksoftirqd to handle it. Therefore we shouldn't - * reach here due to the need_resched() early check in can_stop_idle_tick(). + * reach this code due to the need_resched() early check in can_stop_idle_tick(). * * However if we are between CPUHP_AP_SMPBOOT_THREADS and CPU_TEARDOWN_CPU on the * cpu_down() process, softirqs can still be raised while ksoftirqd is parked, - * triggering the below since wakep_softirqd() is ignored. + * triggering the code below, since wakep_softirqd() is ignored. * */ static bool report_idle_softirq(void) @@ -1044,7 +1044,7 @@ static bool report_idle_softirq(void) if (ratelimit >= 10) return false; - /* On RT, softirqs handling may be waiting on some lock */ + /* On RT, softirq handling may be waiting on some lock */ if (local_bh_blocked()) return false; @@ -1061,8 +1061,8 @@ static bool can_stop_idle_tick(int cpu, struct tick_sched *ts) * If this CPU is offline and it is the one which updates * jiffies, then give up the assignment and let it be taken by * the CPU which runs the tick timer next. If we don't drop - * this here the jiffies might be stale and do_timer() never - * invoked. + * this here, the jiffies might be stale and do_timer() never + * gets invoked. */ if (unlikely(!cpu_online(cpu))) { if (cpu == tick_do_timer_cpu) @@ -1175,12 +1175,23 @@ void tick_nohz_idle_enter(void) } /** - * tick_nohz_irq_exit - update next tick event from interrupt exit + * tick_nohz_irq_exit - Notify the tick about IRQ exit + * + * A timer may have been added/modified/deleted either by the current IRQ, + * or by another place using this IRQ as a notification. This IRQ may have + * also updated the RCU callback list. These events may require a + * re-evaluation of the next tick. Depending on the context: + * + * 1) If the CPU is idle and no resched is pending, just proceed with idle + * time accounting. The next tick will be re-evaluated on the next idle + * loop iteration. + * + * 2) If the CPU is nohz_full: * - * When an interrupt fires while we are idle and it doesn't cause - * a reschedule, it may still add, modify or delete a timer, enqueue - * an RCU callback, etc... - * So we need to re-calculate and reprogram the next tick event. + * 2.1) If there is any tick dependency, restart the tick if stopped. + * + * 2.2) If there is no tick dependency, (re-)evaluate the next tick and + * stop/update it accordingly. */ void tick_nohz_irq_exit(void) { @@ -1208,7 +1219,7 @@ bool tick_nohz_idle_got_tick(void) /** * tick_nohz_get_next_hrtimer - return the next expiration time for the hrtimer - * or the tick, whatever that expires first. Note that, if the tick has been + * or the tick, whichever expires first. Note that, if the tick has been * stopped, it returns the next hrtimer. * * Called from power state control code with interrupts disabled @@ -1252,7 +1263,7 @@ ktime_t tick_nohz_get_sleep_length(ktime_t *delta_next) return *delta_next; /* - * If the next highres timer to expire is earlier than next_event, the + * If the next highres timer to expire is earlier than 'next_event', the * idle governor needs to know that. */ next_event = min_t(u64, next_event, @@ -1296,9 +1307,9 @@ static void tick_nohz_account_idle_time(struct tick_sched *ts, if (vtime_accounting_enabled_this_cpu()) return; /* - * We stopped the tick in idle. Update process times would miss the - * time we slept as update_process_times does only a 1 tick - * accounting. Enforce that this is accounted to idle ! + * We stopped the tick in idle. update_process_times() would miss the + * time we slept, as it does only a 1 tick accounting. + * Enforce that this is accounted to idle ! */ ticks = jiffies - ts->idle_jiffies; /* @@ -1330,11 +1341,20 @@ static void tick_nohz_idle_update_tick(struct tick_sched *ts, ktime_t now) } /** - * tick_nohz_idle_exit - restart the idle tick from the idle task + * tick_nohz_idle_exit - Update the tick upon idle task exit + * + * When the idle task exits, update the tick depending on the + * following situations: + * + * 1) If the CPU is not in nohz_full mode (most cases), then + * restart the tick. + * + * 2) If the CPU is in nohz_full mode (corner case): + * 2.1) If the tick can be kept stopped (no tick dependencies) + * then re-evaluate the next tick and try to keep it stopped + * as long as possible. + * 2.2) If the tick has dependencies, restart the tick. * - * Restart the idle tick when the CPU is woken up from idle - * This also exit the RCU extended quiescent state. The CPU - * can use RCU again after this function is called. */ void tick_nohz_idle_exit(void) { @@ -1364,9 +1384,15 @@ void tick_nohz_idle_exit(void) } /* - * The nohz low res interrupt handler + * In low-resolution mode, the tick handler must be implemented directly + * at the clockevent level. hrtimer can't be used instead, because its + * infrastructure actually relies on the tick itself as a backend in + * low-resolution mode (see hrtimer_run_queues()). + * + * This low-resolution handler still makes use of some hrtimer APIs meanwhile + * for convenience with expiration calculation and forwarding. */ -static void tick_nohz_handler(struct clock_event_device *dev) +static void tick_nohz_lowres_handler(struct clock_event_device *dev) { struct tick_sched *ts = this_cpu_ptr(&tick_cpu_sched); struct pt_regs *regs = get_irq_regs(); @@ -1377,18 +1403,16 @@ static void tick_nohz_handler(struct clock_event_device *dev) tick_sched_do_timer(ts, now); tick_sched_handle(ts, regs); - if (unlikely(ts->tick_stopped)) { - /* - * The clockevent device is not reprogrammed, so change the - * clock event device to ONESHOT_STOPPED to avoid spurious - * interrupts on devices which might not be truly one shot. - */ - tick_program_event(KTIME_MAX, 1); - return; + /* + * In dynticks mode, tick reprogram is deferred: + * - to the idle task if in dynticks-idle + * - to IRQ exit if in full-dynticks. + */ + if (likely(!ts->tick_stopped)) { + hrtimer_forward(&ts->sched_timer, now, TICK_NSEC); + tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); } - hrtimer_forward(&ts->sched_timer, now, TICK_NSEC); - tick_program_event(hrtimer_get_expires(&ts->sched_timer), 1); } static inline void tick_nohz_activate(struct tick_sched *ts, int mode) @@ -1402,7 +1426,7 @@ static inline void tick_nohz_activate(struct tick_sched *ts, int mode) } /** - * tick_nohz_switch_to_nohz - switch to nohz mode + * tick_nohz_switch_to_nohz - switch to NOHZ mode */ static void tick_nohz_switch_to_nohz(void) { @@ -1412,12 +1436,12 @@ static void tick_nohz_switch_to_nohz(void) if (!tick_nohz_enabled) return; - if (tick_switch_to_oneshot(tick_nohz_handler)) + if (tick_switch_to_oneshot(tick_nohz_lowres_handler)) return; /* - * Recycle the hrtimer in ts, so we can share the - * hrtimer_forward with the highres code. + * Recycle the hrtimer in 'ts', so we can share the + * hrtimer_forward_now() function with the highres code. */ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD); /* Get the next period */ @@ -1440,7 +1464,7 @@ static inline void tick_nohz_irq_enter(void) if (ts->idle_active) tick_nohz_stop_idle(ts, now); /* - * If all CPUs are idle. We may need to update a stale jiffies value. + * If all CPUs are idle we may need to update a stale jiffies value. * Note nohz_full is a special case: a timekeeper is guaranteed to stay * alive but it might be busy looping with interrupts disabled in some * rare case (typically stop machine). So we must make sure we have a @@ -1459,7 +1483,7 @@ static inline void tick_nohz_activate(struct tick_sched *ts, int mode) { } #endif /* CONFIG_NO_HZ_COMMON */ /* - * Called from irq_enter to notify about the possible interruption of idle() + * Called from irq_enter() to notify about the possible interruption of idle() */ void tick_irq_enter(void) { @@ -1475,7 +1499,7 @@ void tick_irq_enter(void) * We rearm the timer until we get disabled by the idle code. * Called with interrupts disabled. */ -static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) +static enum hrtimer_restart tick_nohz_highres_handler(struct hrtimer *timer) { struct tick_sched *ts = container_of(timer, struct tick_sched, sched_timer); @@ -1485,15 +1509,19 @@ static enum hrtimer_restart tick_sched_timer(struct hrtimer *timer) tick_sched_do_timer(ts, now); /* - * Do not call, when we are not in irq context and have - * no valid regs pointer + * Do not call when we are not in IRQ context and have + * no valid 'regs' pointer */ if (regs) tick_sched_handle(ts, regs); else ts->next_tick = 0; - /* No need to reprogram if we are in idle or full dynticks mode */ + /* + * In dynticks mode, tick reprogram is deferred: + * - to the idle task if in dynticks-idle + * - to IRQ exit if in full-dynticks. + */ if (unlikely(ts->tick_stopped)) return HRTIMER_NORESTART; @@ -1520,16 +1548,14 @@ void tick_setup_sched_timer(void) struct tick_sched *ts = this_cpu_ptr(&tick_cpu_sched); ktime_t now = ktime_get(); - /* - * Emulate tick processing via per-CPU hrtimers: - */ + /* Emulate tick processing via per-CPU hrtimers: */ hrtimer_init(&ts->sched_timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_HARD); - ts->sched_timer.function = tick_sched_timer; + ts->sched_timer.function = tick_nohz_highres_handler; /* Get the next period (per-CPU) */ hrtimer_set_expires(&ts->sched_timer, tick_init_jiffy_update()); - /* Offset the tick to avert jiffies_lock contention. */ + /* Offset the tick to avert 'jiffies_lock' contention. */ if (sched_skew_tick) { u64 offset = TICK_NSEC >> 1; do_div(offset, num_possible_cpus()); @@ -1589,10 +1615,10 @@ void tick_oneshot_notify(void) } /* - * Check, if a change happened, which makes oneshot possible. + * Check if a change happened, which makes oneshot possible. * - * Called cyclic from the hrtimer softirq (driven by the timer - * softirq) allow_nohz signals, that we can switch into low-res nohz + * Called cyclically from the hrtimer softirq (driven by the timer + * softirq). 'allow_nohz' signals that we can switch into low-res NOHZ * mode, because high resolution timers are disabled (either compile * or runtime). Called with interrupts disabled. */ diff --git a/kernel/torture.c b/kernel/torture.c index c7b475883b..c72ab2d251 100644 --- a/kernel/torture.c +++ b/kernel/torture.c @@ -521,9 +521,8 @@ static void torture_shuffle_task_unregister_all(void) * A special case is when shuffle_idle_cpu = -1, in which case we allow * the tasks to run on all CPUs. */ -static void torture_shuffle_tasks(void) +static void torture_shuffle_tasks(struct torture_random_state *trp) { - DEFINE_TORTURE_RANDOM(rand); struct shuffle_task *stp; cpumask_setall(shuffle_tmp_mask); @@ -544,7 +543,7 @@ static void torture_shuffle_tasks(void) mutex_lock(&shuffle_task_mutex); list_for_each_entry(stp, &shuffle_task_list, st_l) { - if (!random_shuffle || torture_random(&rand) & 0x1) + if (!random_shuffle || torture_random(trp) & 0x1) set_cpus_allowed_ptr(stp->st_t, shuffle_tmp_mask); } mutex_unlock(&shuffle_task_mutex); @@ -563,7 +562,7 @@ static int torture_shuffle(void *arg) VERBOSE_TOROUT_STRING("torture_shuffle task started"); do { torture_hrtimeout_jiffies(shuffle_interval, &rand); - torture_shuffle_tasks(); + torture_shuffle_tasks(&rand); torture_shutdown_absorb("torture_shuffle"); } while (!torture_must_stop()); torture_kthread_stopping("torture_shuffle"); @@ -674,7 +673,7 @@ int torture_shutdown_init(int ssecs, void (*cleanup)(void)) if (ssecs > 0) { shutdown_time = ktime_add(ktime_get(), ktime_set(ssecs, 0)); return torture_create_kthread(torture_shutdown, NULL, - shutdown_task); + shutdown_task); } return 0; } @@ -792,6 +791,13 @@ static void torture_stutter_cleanup(void) stutter_task = NULL; } +static void +torture_print_module_parms(void) +{ + pr_alert("torture module --- %s: disable_onoff_at_boot=%d ftrace_dump_at_shutdown=%d verbose_sleep_frequency=%d verbose_sleep_duration=%d random_shuffle=%d\n", + torture_type, disable_onoff_at_boot, ftrace_dump_at_shutdown, verbose_sleep_frequency, verbose_sleep_duration, random_shuffle); +} + /* * Initialize torture module. Please note that this is -not- invoked via * the usual module_init() mechanism, but rather by an explicit call from @@ -814,6 +820,7 @@ bool torture_init_begin(char *ttype, int v) torture_type = ttype; verbose = v; fullstop = FULLSTOP_DONTSTOP; + torture_print_module_parms(); return true; } EXPORT_SYMBOL_GPL(torture_init_begin); diff --git a/kernel/trace/bpf_trace.c b/kernel/trace/bpf_trace.c index 1d76f3b014..652c40a14d 100644 --- a/kernel/trace/bpf_trace.c +++ b/kernel/trace/bpf_trace.c @@ -120,6 +120,9 @@ unsigned int trace_call_bpf(struct trace_event_call *call, void *ctx) * and don't send kprobe event into ring-buffer, * so return zero here */ + rcu_read_lock(); + bpf_prog_inc_misses_counters(rcu_dereference(call->prog_array)); + rcu_read_unlock(); ret = 0; goto out; } @@ -1252,9 +1255,7 @@ static const struct bpf_func_proto bpf_get_func_arg_cnt_proto = { }; #ifdef CONFIG_KEYS -__diag_push(); -__diag_ignore_all("-Wmissing-prototypes", - "kfuncs which will be used in BPF programs"); +__bpf_kfunc_start_defs(); /** * bpf_lookup_user_key - lookup a key by its serial @@ -1404,7 +1405,7 @@ __bpf_kfunc int bpf_verify_pkcs7_signature(struct bpf_dynptr_kern *data_ptr, } #endif /* CONFIG_SYSTEM_DATA_VERIFICATION */ -__diag_pop(); +__bpf_kfunc_end_defs(); BTF_SET8_START(key_sig_kfunc_set) BTF_ID_FLAGS(func, bpf_lookup_user_key, KF_ACQUIRE | KF_RET_NULL | KF_SLEEPABLE) @@ -2387,7 +2388,8 @@ int bpf_probe_unregister(struct bpf_raw_event_map *btp, struct bpf_prog *prog) int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, u32 *fd_type, const char **buf, - u64 *probe_offset, u64 *probe_addr) + u64 *probe_offset, u64 *probe_addr, + unsigned long *missed) { bool is_tracepoint, is_syscall_tp; struct bpf_prog *prog; @@ -2422,7 +2424,7 @@ int bpf_get_perf_event_info(const struct perf_event *event, u32 *prog_id, #ifdef CONFIG_KPROBE_EVENTS if (flags & TRACE_EVENT_FL_KPROBE) err = bpf_get_kprobe_info(event, fd_type, buf, - probe_offset, probe_addr, + probe_offset, probe_addr, missed, event->attr.type == PERF_TYPE_TRACEPOINT); #endif #ifdef CONFIG_UPROBE_EVENTS @@ -2617,6 +2619,7 @@ static int bpf_kprobe_multi_link_fill_link_info(const struct bpf_link *link, kmulti_link = container_of(link, struct bpf_kprobe_multi_link, link); info->kprobe_multi.count = kmulti_link->cnt; info->kprobe_multi.flags = kmulti_link->flags; + info->kprobe_multi.missed = kmulti_link->fp.nmissed; if (!uaddrs) return 0; @@ -2713,6 +2716,7 @@ kprobe_multi_link_prog_run(struct bpf_kprobe_multi_link *link, int err; if (unlikely(__this_cpu_inc_return(bpf_prog_active) != 1)) { + bpf_prog_inc_misses_counter(link->link.prog); err = 0; goto out; } diff --git a/kernel/trace/fprobe.c b/kernel/trace/fprobe.c index 881f90f0cb..6cd2a4e3af 100644 --- a/kernel/trace/fprobe.c +++ b/kernel/trace/fprobe.c @@ -187,7 +187,7 @@ static void fprobe_init(struct fprobe *fp) static int fprobe_init_rethook(struct fprobe *fp, int num) { - int i, size; + int size; if (num <= 0) return -EINVAL; @@ -205,26 +205,18 @@ static int fprobe_init_rethook(struct fprobe *fp, int num) if (size <= 0) return -EINVAL; - fp->rethook = rethook_alloc((void *)fp, fprobe_exit_handler); - if (!fp->rethook) - return -ENOMEM; - for (i = 0; i < size; i++) { - struct fprobe_rethook_node *node; - - node = kzalloc(sizeof(*node) + fp->entry_data_size, GFP_KERNEL); - if (!node) { - rethook_free(fp->rethook); - fp->rethook = NULL; - return -ENOMEM; - } - rethook_add_node(fp->rethook, &node->node); - } + /* Initialize rethook */ + fp->rethook = rethook_alloc((void *)fp, fprobe_exit_handler, + sizeof(struct fprobe_rethook_node), size); + if (IS_ERR(fp->rethook)) + return PTR_ERR(fp->rethook); + return 0; } static void fprobe_fail_cleanup(struct fprobe *fp) { - if (fp->rethook) { + if (!IS_ERR_OR_NULL(fp->rethook)) { /* Don't need to cleanup rethook->handler because this is not used. */ rethook_free(fp->rethook); fp->rethook = NULL; @@ -379,14 +371,14 @@ int unregister_fprobe(struct fprobe *fp) if (!fprobe_is_registered(fp)) return -EINVAL; - if (fp->rethook) + if (!IS_ERR_OR_NULL(fp->rethook)) rethook_stop(fp->rethook); ret = unregister_ftrace_function(&fp->ops); if (ret < 0) return ret; - if (fp->rethook) + if (!IS_ERR_OR_NULL(fp->rethook)) rethook_free(fp->rethook); ftrace_free_filter(&fp->ops); diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index b01ae7d360..83ba342aef 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -5325,7 +5325,17 @@ static LIST_HEAD(ftrace_direct_funcs); static int register_ftrace_function_nolock(struct ftrace_ops *ops); +/* + * If there are multiple ftrace_ops, use SAVE_REGS by default, so that direct + * call will be jumped from ftrace_regs_caller. Only if the architecture does + * not support ftrace_regs_caller but direct_call, use SAVE_ARGS so that it + * jumps from ftrace_caller for multiple ftrace_ops. + */ +#ifndef CONFIG_HAVE_DYNAMIC_FTRACE_WITH_REGS #define MULTI_FLAGS (FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_ARGS) +#else +#define MULTI_FLAGS (FTRACE_OPS_FL_DIRECT | FTRACE_OPS_FL_SAVE_REGS) +#endif static int check_direct_multi(struct ftrace_ops *ops) { diff --git a/kernel/trace/rethook.c b/kernel/trace/rethook.c index 3cebcbaf35..fa03094e9e 100644 --- a/kernel/trace/rethook.c +++ b/kernel/trace/rethook.c @@ -8,7 +8,6 @@ #include <linux/preempt.h> #include <linux/rethook.h> #include <linux/slab.h> -#include <linux/sort.h> /* Return hook list (shadow stack by list) */ @@ -36,21 +35,7 @@ void rethook_flush_task(struct task_struct *tk) static void rethook_free_rcu(struct rcu_head *head) { struct rethook *rh = container_of(head, struct rethook, rcu); - struct rethook_node *rhn; - struct freelist_node *node; - int count = 1; - - node = rh->pool.head; - while (node) { - rhn = container_of(node, struct rethook_node, freelist); - node = node->next; - kfree(rhn); - count++; - } - - /* The rh->ref is the number of pooled node + 1 */ - if (refcount_sub_and_test(count, &rh->ref)) - kfree(rh); + objpool_fini(&rh->pool); } /** @@ -83,6 +68,20 @@ void rethook_free(struct rethook *rh) call_rcu(&rh->rcu, rethook_free_rcu); } +static int rethook_init_node(void *nod, void *context) +{ + struct rethook_node *node = nod; + + node->rethook = context; + return 0; +} + +static int rethook_fini_pool(struct objpool_head *head, void *context) +{ + kfree(context); + return 0; +} + static inline rethook_handler_t rethook_get_handler(struct rethook *rh) { return (rethook_handler_t)rcu_dereference_check(rh->handler, @@ -92,51 +91,45 @@ static inline rethook_handler_t rethook_get_handler(struct rethook *rh) /** * rethook_alloc() - Allocate struct rethook. * @data: a data to pass the @handler when hooking the return. - * @handler: the return hook callback function. + * @handler: the return hook callback function, must NOT be NULL + * @size: node size: rethook node and additional data + * @num: number of rethook nodes to be preallocated * * Allocate and initialize a new rethook with @data and @handler. - * Return NULL if memory allocation fails or @handler is NULL. + * Return pointer of new rethook, or error codes for failures. + * * Note that @handler == NULL means this rethook is going to be freed. */ -struct rethook *rethook_alloc(void *data, rethook_handler_t handler) +struct rethook *rethook_alloc(void *data, rethook_handler_t handler, + int size, int num) { - struct rethook *rh = kzalloc(sizeof(struct rethook), GFP_KERNEL); + struct rethook *rh; - if (!rh || !handler) { - kfree(rh); - return NULL; - } + if (!handler || num <= 0 || size < sizeof(struct rethook_node)) + return ERR_PTR(-EINVAL); + + rh = kzalloc(sizeof(struct rethook), GFP_KERNEL); + if (!rh) + return ERR_PTR(-ENOMEM); rh->data = data; rcu_assign_pointer(rh->handler, handler); - rh->pool.head = NULL; - refcount_set(&rh->ref, 1); + /* initialize the objpool for rethook nodes */ + if (objpool_init(&rh->pool, num, size, GFP_KERNEL, rh, + rethook_init_node, rethook_fini_pool)) { + kfree(rh); + return ERR_PTR(-ENOMEM); + } return rh; } -/** - * rethook_add_node() - Add a new node to the rethook. - * @rh: the struct rethook. - * @node: the struct rethook_node to be added. - * - * Add @node to @rh. User must allocate @node (as a part of user's - * data structure.) The @node fields are initialized in this function. - */ -void rethook_add_node(struct rethook *rh, struct rethook_node *node) -{ - node->rethook = rh; - freelist_add(&node->freelist, &rh->pool); - refcount_inc(&rh->ref); -} - static void free_rethook_node_rcu(struct rcu_head *head) { struct rethook_node *node = container_of(head, struct rethook_node, rcu); + struct rethook *rh = node->rethook; - if (refcount_dec_and_test(&node->rethook->ref)) - kfree(node->rethook); - kfree(node); + objpool_drop(node, &rh->pool); } /** @@ -152,7 +145,7 @@ void rethook_recycle(struct rethook_node *node) handler = rethook_get_handler(node->rethook); if (likely(handler)) - freelist_add(&node->freelist, &node->rethook->pool); + objpool_push(node, &node->rethook->pool); else call_rcu(&node->rcu, free_rethook_node_rcu); } @@ -168,7 +161,6 @@ NOKPROBE_SYMBOL(rethook_recycle); struct rethook_node *rethook_try_get(struct rethook *rh) { rethook_handler_t handler = rethook_get_handler(rh); - struct freelist_node *fn; /* Check whether @rh is going to be freed. */ if (unlikely(!handler)) @@ -183,11 +175,7 @@ struct rethook_node *rethook_try_get(struct rethook *rh) if (unlikely(!rcu_is_watching())) return NULL; - fn = freelist_try_get(&rh->pool); - if (!fn) - return NULL; - - return container_of(fn, struct rethook_node, freelist); + return (struct rethook_node *)objpool_pop(&rh->pool); } NOKPROBE_SYMBOL(rethook_try_get); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index f232cf56fa..6fa67c297e 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -1091,7 +1091,7 @@ __poll_t ring_buffer_poll_wait(struct trace_buffer *buffer, int cpu, full = 0; } else { if (!cpumask_test_cpu(cpu, buffer->cpumask)) - return -EINVAL; + return EPOLLERR; cpu_buffer = buffer->buffers[cpu]; work = &cpu_buffer->irq_work; @@ -2021,7 +2021,7 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer) retries = 10; success = false; while (retries--) { - struct list_head *head_page, *prev_page, *r; + struct list_head *head_page, *prev_page; struct list_head *last_page, *first_page; struct list_head *head_page_with_bit; struct buffer_page *hpage = rb_set_head_page(cpu_buffer); @@ -2040,9 +2040,9 @@ rb_insert_pages(struct ring_buffer_per_cpu *cpu_buffer) last_page->next = head_page_with_bit; first_page->prev = prev_page; - r = cmpxchg(&prev_page->next, head_page_with_bit, first_page); - - if (r == head_page_with_bit) { + /* caution: head_page_with_bit gets updated on cmpxchg failure */ + if (try_cmpxchg(&prev_page->next, + &head_page_with_bit, first_page)) { /* * yay, we replaced the page pointer to our new list, * now, we just have to update to head page's prev diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index fc00356a5a..3fdc57450e 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -39,6 +39,7 @@ #include <linux/ctype.h> #include <linux/init.h> #include <linux/panic_notifier.h> +#include <linux/kmemleak.h> #include <linux/poll.h> #include <linux/nmi.h> #include <linux/fs.h> @@ -54,12 +55,6 @@ #include "trace.h" #include "trace_output.h" -/* - * On boot up, the ring buffer is set to the minimum size, so that - * we do not waste memory on systems that are not using tracing. - */ -bool ring_buffer_expanded; - #ifdef CONFIG_FTRACE_STARTUP_TEST /* * We need to change this state when a selftest is running. @@ -202,7 +197,7 @@ static int __init set_cmdline_ftrace(char *str) strscpy(bootup_tracer_buf, str, MAX_TRACER_SIZE); default_bootup_tracer = bootup_tracer_buf; /* We are using ftrace early, expand it */ - ring_buffer_expanded = true; + trace_set_ring_buffer_expanded(NULL); return 1; } __setup("ftrace=", set_cmdline_ftrace); @@ -247,7 +242,7 @@ static int __init boot_alloc_snapshot(char *str) } else { allocate_snapshot = true; /* We also need the main ring buffer expanded */ - ring_buffer_expanded = true; + trace_set_ring_buffer_expanded(NULL); } return 1; } @@ -490,6 +485,13 @@ static struct trace_array global_trace = { .trace_flags = TRACE_DEFAULT_FLAGS, }; +void trace_set_ring_buffer_expanded(struct trace_array *tr) +{ + if (!tr) + tr = &global_trace; + tr->ring_buffer_expanded = true; +} + LIST_HEAD(ftrace_trace_arrays); int trace_array_get(struct trace_array *this_tr) @@ -1730,15 +1732,15 @@ static ssize_t trace_seq_to_buffer(struct trace_seq *s, void *buf, size_t cnt) { int len; - if (trace_seq_used(s) <= s->seq.readpos) + if (trace_seq_used(s) <= s->readpos) return -EBUSY; - len = trace_seq_used(s) - s->seq.readpos; + len = trace_seq_used(s) - s->readpos; if (cnt > len) cnt = len; - memcpy(buf, s->buffer + s->seq.readpos, cnt); + memcpy(buf, s->buffer + s->readpos, cnt); - s->seq.readpos += cnt; + s->readpos += cnt; return cnt; } @@ -2026,7 +2028,7 @@ static int run_tracer_selftest(struct tracer *type) #ifdef CONFIG_TRACER_MAX_TRACE if (type->use_max_tr) { /* If we expanded the buffers, make sure the max is expanded too */ - if (ring_buffer_expanded) + if (tr->ring_buffer_expanded) ring_buffer_resize(tr->max_buffer.buffer, trace_buf_size, RING_BUFFER_ALL_CPUS); tr->allocated_snapshot = true; @@ -2052,7 +2054,7 @@ static int run_tracer_selftest(struct tracer *type) tr->allocated_snapshot = false; /* Shrink the max buffer again */ - if (ring_buffer_expanded) + if (tr->ring_buffer_expanded) ring_buffer_resize(tr->max_buffer.buffer, 1, RING_BUFFER_ALL_CPUS); } @@ -2311,7 +2313,7 @@ struct saved_cmdlines_buffer { unsigned *map_cmdline_to_pid; unsigned cmdline_num; int cmdline_idx; - char *saved_cmdlines; + char saved_cmdlines[]; }; static struct saved_cmdlines_buffer *savedcmd; @@ -2325,47 +2327,60 @@ static inline void set_cmdline(int idx, const char *cmdline) strncpy(get_saved_cmdlines(idx), cmdline, TASK_COMM_LEN); } -static int allocate_cmdlines_buffer(unsigned int val, - struct saved_cmdlines_buffer *s) +static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) +{ + int order = get_order(sizeof(*s) + s->cmdline_num * TASK_COMM_LEN); + + kfree(s->map_cmdline_to_pid); + kmemleak_free(s); + free_pages((unsigned long)s, order); +} + +static struct saved_cmdlines_buffer *allocate_cmdlines_buffer(unsigned int val) { + struct saved_cmdlines_buffer *s; + struct page *page; + int orig_size, size; + int order; + + /* Figure out how much is needed to hold the given number of cmdlines */ + orig_size = sizeof(*s) + val * TASK_COMM_LEN; + order = get_order(orig_size); + size = 1 << (order + PAGE_SHIFT); + page = alloc_pages(GFP_KERNEL, order); + if (!page) + return NULL; + + s = page_address(page); + kmemleak_alloc(s, size, 1, GFP_KERNEL); + memset(s, 0, sizeof(*s)); + + /* Round up to actual allocation */ + val = (size - sizeof(*s)) / TASK_COMM_LEN; + s->cmdline_num = val; + s->map_cmdline_to_pid = kmalloc_array(val, sizeof(*s->map_cmdline_to_pid), GFP_KERNEL); - if (!s->map_cmdline_to_pid) - return -ENOMEM; - - s->saved_cmdlines = kmalloc_array(TASK_COMM_LEN, val, GFP_KERNEL); - if (!s->saved_cmdlines) { - kfree(s->map_cmdline_to_pid); - return -ENOMEM; + if (!s->map_cmdline_to_pid) { + free_saved_cmdlines_buffer(s); + return NULL; } s->cmdline_idx = 0; - s->cmdline_num = val; memset(&s->map_pid_to_cmdline, NO_CMDLINE_MAP, sizeof(s->map_pid_to_cmdline)); memset(s->map_cmdline_to_pid, NO_CMDLINE_MAP, val * sizeof(*s->map_cmdline_to_pid)); - return 0; + return s; } static int trace_create_savedcmd(void) { - int ret; - - savedcmd = kmalloc(sizeof(*savedcmd), GFP_KERNEL); - if (!savedcmd) - return -ENOMEM; - - ret = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT, savedcmd); - if (ret < 0) { - kfree(savedcmd); - savedcmd = NULL; - return -ENOMEM; - } + savedcmd = allocate_cmdlines_buffer(SAVED_CMDLINES_DEFAULT); - return 0; + return savedcmd ? 0 : -ENOMEM; } int is_tracing_stopped(void) @@ -3374,7 +3389,7 @@ void trace_printk_init_buffers(void) pr_warn("**********************************************************\n"); /* Expand the buffers to set size */ - tracing_update_buffers(); + tracing_update_buffers(&global_trace); buffers_allocated = 1; @@ -3798,15 +3813,6 @@ static bool trace_safe_str(struct trace_iterator *iter, const char *str, return false; } -static const char *show_buffer(struct trace_seq *s) -{ - struct seq_buf *seq = &s->seq; - - seq_buf_terminate(seq); - - return seq->buffer; -} - static DEFINE_STATIC_KEY_FALSE(trace_no_verify); static int test_can_verify_check(const char *fmt, ...) @@ -3946,7 +3952,7 @@ void trace_check_vprintf(struct trace_iterator *iter, const char *fmt, */ if (WARN_ONCE(!trace_safe_str(iter, str, star, len), "fmt: '%s' current_buffer: '%s'", - fmt, show_buffer(&iter->seq))) { + fmt, seq_buf_str(&iter->seq.seq))) { int ret; /* Try to safely read the string */ @@ -6056,26 +6062,14 @@ tracing_saved_cmdlines_size_read(struct file *filp, char __user *ubuf, return simple_read_from_buffer(ubuf, cnt, ppos, buf, r); } -static void free_saved_cmdlines_buffer(struct saved_cmdlines_buffer *s) -{ - kfree(s->saved_cmdlines); - kfree(s->map_cmdline_to_pid); - kfree(s); -} - static int tracing_resize_saved_cmdlines(unsigned int val) { struct saved_cmdlines_buffer *s, *savedcmd_temp; - s = kmalloc(sizeof(*s), GFP_KERNEL); + s = allocate_cmdlines_buffer(val); if (!s) return -ENOMEM; - if (allocate_cmdlines_buffer(val, s) < 0) { - kfree(s); - return -ENOMEM; - } - preempt_disable(); arch_spin_lock(&trace_cmdline_lock); savedcmd_temp = savedcmd; @@ -6370,7 +6364,7 @@ static int __tracing_resize_ring_buffer(struct trace_array *tr, * we use the size that was given, and we can forget about * expanding it later. */ - ring_buffer_expanded = true; + trace_set_ring_buffer_expanded(tr); /* May be called before buffers are initialized */ if (!tr->array_buffer.buffer) @@ -6451,6 +6445,7 @@ out: /** * tracing_update_buffers - used by tracing facility to expand ring buffers + * @tr: The tracing instance * * To save on memory when the tracing is never used on a system with it * configured in. The ring buffers are set to a minimum size. But once @@ -6459,13 +6454,13 @@ out: * * This function is to be called when a tracer is about to be used. */ -int tracing_update_buffers(void) +int tracing_update_buffers(struct trace_array *tr) { int ret = 0; mutex_lock(&trace_types_lock); - if (!ring_buffer_expanded) - ret = __tracing_resize_ring_buffer(&global_trace, trace_buf_size, + if (!tr->ring_buffer_expanded) + ret = __tracing_resize_ring_buffer(tr, trace_buf_size, RING_BUFFER_ALL_CPUS); mutex_unlock(&trace_types_lock); @@ -6519,7 +6514,7 @@ int tracing_set_tracer(struct trace_array *tr, const char *buf) mutex_lock(&trace_types_lock); - if (!ring_buffer_expanded) { + if (!tr->ring_buffer_expanded) { ret = __tracing_resize_ring_buffer(tr, trace_buf_size, RING_BUFFER_ALL_CPUS); if (ret < 0) @@ -7005,7 +7000,7 @@ waitagain: /* Now copy what we have to the user */ sret = trace_seq_to_user(&iter->seq, ubuf, cnt); - if (iter->seq.seq.readpos >= trace_seq_used(&iter->seq)) + if (iter->seq.readpos >= trace_seq_used(&iter->seq)) trace_seq_init(&iter->seq); /* @@ -7191,7 +7186,7 @@ tracing_entries_read(struct file *filp, char __user *ubuf, } if (buf_size_same) { - if (!ring_buffer_expanded) + if (!tr->ring_buffer_expanded) r = sprintf(buf, "%lu (expanded: %lu)\n", size >> 10, trace_buf_size >> 10); @@ -7248,10 +7243,10 @@ tracing_total_entries_read(struct file *filp, char __user *ubuf, mutex_lock(&trace_types_lock); for_each_tracing_cpu(cpu) { size += per_cpu_ptr(tr->array_buffer.data, cpu)->entries >> 10; - if (!ring_buffer_expanded) + if (!tr->ring_buffer_expanded) expanded_size += trace_buf_size >> 10; } - if (ring_buffer_expanded) + if (tr->ring_buffer_expanded) r = sprintf(buf, "%lu\n", size); else r = sprintf(buf, "%lu (expanded: %lu)\n", size, expanded_size); @@ -7645,7 +7640,7 @@ tracing_snapshot_write(struct file *filp, const char __user *ubuf, size_t cnt, unsigned long val; int ret; - ret = tracing_update_buffers(); + ret = tracing_update_buffers(tr); if (ret < 0) return ret; @@ -9549,6 +9544,9 @@ static struct trace_array *trace_array_create(const char *name) if (allocate_trace_buffers(tr, trace_buf_size) < 0) goto out_free_tr; + /* The ring buffer is defaultly expanded */ + trace_set_ring_buffer_expanded(tr); + if (ftrace_allocate_ftrace_ops(tr) < 0) goto out_free_tr; @@ -9758,7 +9756,6 @@ static __init void create_trace_instances(struct dentry *d_tracer) static void init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) { - struct trace_event_file *file; int cpu; trace_create_file("available_tracers", TRACE_MODE_READ, d_tracer, @@ -9791,11 +9788,7 @@ init_tracer_tracefs(struct trace_array *tr, struct dentry *d_tracer) trace_create_file("trace_marker", 0220, d_tracer, tr, &tracing_mark_fops); - file = __find_event_file(tr, "ftrace", "print"); - if (file && file->ef) - eventfs_add_file("trigger", TRACE_MODE_WRITE, file->ef, - file, &event_trigger_fops); - tr->trace_marker_file = file; + tr->trace_marker_file = __find_event_file(tr, "ftrace", "print"); trace_create_file("trace_marker_raw", 0220, d_tracer, tr, &tracing_mark_raw_fops); @@ -10443,7 +10436,7 @@ __init static int tracer_alloc_buffers(void) trace_printk_init_buffers(); /* To save memory, keep the ring buffer size to its minimum */ - if (ring_buffer_expanded) + if (global_trace.ring_buffer_expanded) ring_buf_size = trace_buf_size; else ring_buf_size = 1; diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 51c0a97033..0489e72c81 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -381,7 +381,7 @@ struct trace_array { struct dentry *dir; struct dentry *options; struct dentry *percpu_dir; - struct dentry *event_dir; + struct eventfs_inode *event_dir; struct trace_options *topts; struct list_head systems; struct list_head events; @@ -410,6 +410,11 @@ struct trace_array { struct cond_snapshot *cond_snapshot; #endif struct trace_func_repeats __percpu *last_func_repeats; + /* + * On boot up, the ring buffer is set to the minimum size, so that + * we do not waste memory on systems that are not using tracing. + */ + bool ring_buffer_expanded; }; enum { @@ -762,7 +767,7 @@ extern int DYN_FTRACE_TEST_NAME(void); #define DYN_FTRACE_TEST_NAME2 trace_selftest_dynamic_test_func2 extern int DYN_FTRACE_TEST_NAME2(void); -extern bool ring_buffer_expanded; +extern void trace_set_ring_buffer_expanded(struct trace_array *tr); extern bool tracing_selftest_disabled; #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -1306,7 +1311,7 @@ static inline void trace_branch_disable(void) #endif /* CONFIG_BRANCH_TRACER */ /* set ring buffers to default size if not already done so */ -int tracing_update_buffers(void); +int tracing_update_buffers(struct trace_array *tr); union trace_synth_field { u8 as_u8; @@ -1345,7 +1350,7 @@ struct trace_subsystem_dir { struct list_head list; struct event_subsystem *subsystem; struct trace_array *tr; - struct eventfs_file *ef; + struct eventfs_inode *ei; int ref_count; int nr_events; }; diff --git a/kernel/trace/trace_btf.c b/kernel/trace/trace_btf.c index ca224d53bf..5bbdbcbbde 100644 --- a/kernel/trace/trace_btf.c +++ b/kernel/trace/trace_btf.c @@ -91,8 +91,8 @@ retry: for_each_member(i, type, member) { if (!member->name_off) { /* Anonymous union/struct: push it for later use */ - type = btf_type_skip_modifiers(btf, member->type, &tid); - if (type && top < BTF_ANON_STACK_MAX) { + if (btf_type_skip_modifiers(btf, member->type, &tid) && + top < BTF_ANON_STACK_MAX) { anon_stack[top].tid = tid; anon_stack[top++].offset = cur_offset + member->offset; diff --git a/kernel/trace/trace_eprobe.c b/kernel/trace/trace_eprobe.c index 72714cbf47..03c851f579 100644 --- a/kernel/trace/trace_eprobe.c +++ b/kernel/trace/trace_eprobe.c @@ -788,12 +788,9 @@ find_and_get_event(const char *system, const char *event_name) name = trace_event_name(tp_event); if (!name || strcmp(event_name, name)) continue; - if (!trace_event_try_get_ref(tp_event)) { + if (!trace_event_try_get_ref(tp_event)) return NULL; - break; - } return tp_event; - break; } return NULL; } diff --git a/kernel/trace/trace_events.c b/kernel/trace/trace_events.c index 82cb22ad6d..f29e815ca5 100644 --- a/kernel/trace/trace_events.c +++ b/kernel/trace/trace_events.c @@ -984,7 +984,7 @@ static void remove_subsystem(struct trace_subsystem_dir *dir) return; if (!--dir->nr_events) { - eventfs_remove(dir->ef); + eventfs_remove_dir(dir->ei); list_del(&dir->list); __put_system_dir(dir); } @@ -1013,7 +1013,7 @@ void event_file_put(struct trace_event_file *file) static void remove_event_file_dir(struct trace_event_file *file) { - eventfs_remove(file->ef); + eventfs_remove_dir(file->ei); list_del(&file->list); remove_subsystem(file->system); free_event_filter(file->filter); @@ -1188,7 +1188,7 @@ ftrace_event_write(struct file *file, const char __user *ubuf, if (!cnt) return 0; - ret = tracing_update_buffers(); + ret = tracing_update_buffers(tr); if (ret < 0) return ret; @@ -1419,18 +1419,20 @@ event_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret) return ret; - ret = tracing_update_buffers(); - if (ret < 0) - return ret; - switch (val) { case 0: case 1: ret = -ENODEV; mutex_lock(&event_mutex); file = event_file_data(filp); - if (likely(file && !(file->flags & EVENT_FILE_FL_FREED))) + if (likely(file && !(file->flags & EVENT_FILE_FL_FREED))) { + ret = tracing_update_buffers(file->tr); + if (ret < 0) { + mutex_unlock(&event_mutex); + return ret; + } ret = ftrace_event_enable_disable(file, val); + } mutex_unlock(&event_mutex); break; @@ -1504,7 +1506,7 @@ system_enable_write(struct file *filp, const char __user *ubuf, size_t cnt, if (ret) return ret; - ret = tracing_update_buffers(); + ret = tracing_update_buffers(dir->tr); if (ret < 0) return ret; @@ -1978,7 +1980,7 @@ event_pid_write(struct file *filp, const char __user *ubuf, if (!cnt) return 0; - ret = tracing_update_buffers(); + ret = tracing_update_buffers(tr); if (ret < 0) return ret; @@ -2302,14 +2304,40 @@ create_new_subsystem(const char *name) return NULL; } -static struct eventfs_file * +static int system_callback(const char *name, umode_t *mode, void **data, + const struct file_operations **fops) +{ + if (strcmp(name, "filter") == 0) + *fops = &ftrace_subsystem_filter_fops; + + else if (strcmp(name, "enable") == 0) + *fops = &ftrace_system_enable_fops; + + else + return 0; + + *mode = TRACE_MODE_WRITE; + return 1; +} + +static struct eventfs_inode * event_subsystem_dir(struct trace_array *tr, const char *name, - struct trace_event_file *file, struct dentry *parent) + struct trace_event_file *file, struct eventfs_inode *parent) { struct event_subsystem *system, *iter; struct trace_subsystem_dir *dir; - struct eventfs_file *ef; - int res; + struct eventfs_inode *ei; + int nr_entries; + static struct eventfs_entry system_entries[] = { + { + .name = "filter", + .callback = system_callback, + }, + { + .name = "enable", + .callback = system_callback, + } + }; /* First see if we did not already create this dir */ list_for_each_entry(dir, &tr->systems, list) { @@ -2317,7 +2345,7 @@ event_subsystem_dir(struct trace_array *tr, const char *name, if (strcmp(system->name, name) == 0) { dir->nr_events++; file->system = dir; - return dir->ef; + return dir->ei; } } @@ -2341,39 +2369,29 @@ event_subsystem_dir(struct trace_array *tr, const char *name, } else __get_system(system); - ef = eventfs_add_subsystem_dir(name, parent); - if (IS_ERR(ef)) { + /* ftrace only has directories no files */ + if (strcmp(name, "ftrace") == 0) + nr_entries = 0; + else + nr_entries = ARRAY_SIZE(system_entries); + + ei = eventfs_create_dir(name, parent, system_entries, nr_entries, dir); + if (IS_ERR(ei)) { pr_warn("Failed to create system directory %s\n", name); __put_system(system); goto out_free; } - dir->ef = ef; + dir->ei = ei; dir->tr = tr; dir->ref_count = 1; dir->nr_events = 1; dir->subsystem = system; file->system = dir; - /* the ftrace system is special, do not create enable or filter files */ - if (strcmp(name, "ftrace") != 0) { - - res = eventfs_add_file("filter", TRACE_MODE_WRITE, - dir->ef, dir, - &ftrace_subsystem_filter_fops); - if (res) { - kfree(system->filter); - system->filter = NULL; - pr_warn("Could not create tracefs '%s/filter' entry\n", name); - } - - eventfs_add_file("enable", TRACE_MODE_WRITE, dir->ef, dir, - &ftrace_system_enable_fops); - } - list_add(&dir->list, &tr->systems); - return dir->ef; + return dir->ei; out_free: kfree(dir); @@ -2422,15 +2440,134 @@ event_define_fields(struct trace_event_call *call) return ret; } +static int event_callback(const char *name, umode_t *mode, void **data, + const struct file_operations **fops) +{ + struct trace_event_file *file = *data; + struct trace_event_call *call = file->event_call; + + if (strcmp(name, "format") == 0) { + *mode = TRACE_MODE_READ; + *fops = &ftrace_event_format_fops; + *data = call; + return 1; + } + + /* + * Only event directories that can be enabled should have + * triggers or filters, with the exception of the "print" + * event that can have a "trigger" file. + */ + if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) { + if (call->class->reg && strcmp(name, "enable") == 0) { + *mode = TRACE_MODE_WRITE; + *fops = &ftrace_enable_fops; + return 1; + } + + if (strcmp(name, "filter") == 0) { + *mode = TRACE_MODE_WRITE; + *fops = &ftrace_event_filter_fops; + return 1; + } + } + + if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE) || + strcmp(trace_event_name(call), "print") == 0) { + if (strcmp(name, "trigger") == 0) { + *mode = TRACE_MODE_WRITE; + *fops = &event_trigger_fops; + return 1; + } + } + +#ifdef CONFIG_PERF_EVENTS + if (call->event.type && call->class->reg && + strcmp(name, "id") == 0) { + *mode = TRACE_MODE_READ; + *data = (void *)(long)call->event.type; + *fops = &ftrace_event_id_fops; + return 1; + } +#endif + +#ifdef CONFIG_HIST_TRIGGERS + if (strcmp(name, "hist") == 0) { + *mode = TRACE_MODE_READ; + *fops = &event_hist_fops; + return 1; + } +#endif +#ifdef CONFIG_HIST_TRIGGERS_DEBUG + if (strcmp(name, "hist_debug") == 0) { + *mode = TRACE_MODE_READ; + *fops = &event_hist_debug_fops; + return 1; + } +#endif +#ifdef CONFIG_TRACE_EVENT_INJECT + if (call->event.type && call->class->reg && + strcmp(name, "inject") == 0) { + *mode = 0200; + *fops = &event_inject_fops; + return 1; + } +#endif + return 0; +} + static int -event_create_dir(struct dentry *parent, struct trace_event_file *file) +event_create_dir(struct eventfs_inode *parent, struct trace_event_file *file) { struct trace_event_call *call = file->event_call; - struct eventfs_file *ef_subsystem = NULL; struct trace_array *tr = file->tr; - struct eventfs_file *ef; + struct eventfs_inode *e_events; + struct eventfs_inode *ei; const char *name; + int nr_entries; int ret; + static struct eventfs_entry event_entries[] = { + { + .name = "enable", + .callback = event_callback, + }, + { + .name = "filter", + .callback = event_callback, + }, + { + .name = "trigger", + .callback = event_callback, + }, + { + .name = "format", + .callback = event_callback, + }, +#ifdef CONFIG_PERF_EVENTS + { + .name = "id", + .callback = event_callback, + }, +#endif +#ifdef CONFIG_HIST_TRIGGERS + { + .name = "hist", + .callback = event_callback, + }, +#endif +#ifdef CONFIG_HIST_TRIGGERS_DEBUG + { + .name = "hist_debug", + .callback = event_callback, + }, +#endif +#ifdef CONFIG_TRACE_EVENT_INJECT + { + .name = "inject", + .callback = event_callback, + }, +#endif + }; /* * If the trace point header did not define TRACE_SYSTEM @@ -2440,29 +2577,20 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file) if (WARN_ON_ONCE(strcmp(call->class->system, TRACE_SYSTEM) == 0)) return -ENODEV; - ef_subsystem = event_subsystem_dir(tr, call->class->system, file, parent); - if (!ef_subsystem) + e_events = event_subsystem_dir(tr, call->class->system, file, parent); + if (!e_events) return -ENOMEM; + nr_entries = ARRAY_SIZE(event_entries); + name = trace_event_name(call); - ef = eventfs_add_dir(name, ef_subsystem); - if (IS_ERR(ef)) { + ei = eventfs_create_dir(name, e_events, event_entries, nr_entries, file); + if (IS_ERR(ei)) { pr_warn("Could not create tracefs '%s' directory\n", name); return -1; } - file->ef = ef; - - if (call->class->reg && !(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) - eventfs_add_file("enable", TRACE_MODE_WRITE, file->ef, file, - &ftrace_enable_fops); - -#ifdef CONFIG_PERF_EVENTS - if (call->event.type && call->class->reg) - eventfs_add_file("id", TRACE_MODE_READ, file->ef, - (void *)(long)call->event.type, - &ftrace_event_id_fops); -#endif + file->ei = ei; ret = event_define_fields(call); if (ret < 0) { @@ -2470,35 +2598,6 @@ event_create_dir(struct dentry *parent, struct trace_event_file *file) return ret; } - /* - * Only event directories that can be enabled should have - * triggers or filters. - */ - if (!(call->flags & TRACE_EVENT_FL_IGNORE_ENABLE)) { - eventfs_add_file("filter", TRACE_MODE_WRITE, file->ef, - file, &ftrace_event_filter_fops); - - eventfs_add_file("trigger", TRACE_MODE_WRITE, file->ef, - file, &event_trigger_fops); - } - -#ifdef CONFIG_HIST_TRIGGERS - eventfs_add_file("hist", TRACE_MODE_READ, file->ef, file, - &event_hist_fops); -#endif -#ifdef CONFIG_HIST_TRIGGERS_DEBUG - eventfs_add_file("hist_debug", TRACE_MODE_READ, file->ef, file, - &event_hist_debug_fops); -#endif - eventfs_add_file("format", TRACE_MODE_READ, file->ef, call, - &ftrace_event_format_fops); - -#ifdef CONFIG_TRACE_EVENT_INJECT - if (call->event.type && call->class->reg) - eventfs_add_file("inject", 0200, file->ef, file, - &event_inject_fops); -#endif - return 0; } @@ -2847,7 +2946,7 @@ static __init int setup_trace_triggers(char *str) int i; strscpy(bootup_trigger_buf, str, COMMAND_LINE_SIZE); - ring_buffer_expanded = true; + trace_set_ring_buffer_expanded(NULL); disable_tracing_selftest("running event triggers"); buf = bootup_trigger_buf; @@ -3637,37 +3736,72 @@ static char bootup_event_buf[COMMAND_LINE_SIZE] __initdata; static __init int setup_trace_event(char *str) { strscpy(bootup_event_buf, str, COMMAND_LINE_SIZE); - ring_buffer_expanded = true; + trace_set_ring_buffer_expanded(NULL); disable_tracing_selftest("running event tracing"); return 1; } __setup("trace_event=", setup_trace_event); +static int events_callback(const char *name, umode_t *mode, void **data, + const struct file_operations **fops) +{ + if (strcmp(name, "enable") == 0) { + *mode = TRACE_MODE_WRITE; + *fops = &ftrace_tr_enable_fops; + return 1; + } + + if (strcmp(name, "header_page") == 0) + *data = ring_buffer_print_page_header; + + else if (strcmp(name, "header_event") == 0) + *data = ring_buffer_print_entry_header; + + else + return 0; + + *mode = TRACE_MODE_READ; + *fops = &ftrace_show_header_fops; + return 1; +} + /* Expects to have event_mutex held when called */ static int create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) { - struct dentry *d_events; + struct eventfs_inode *e_events; struct dentry *entry; - int error = 0; + int nr_entries; + static struct eventfs_entry events_entries[] = { + { + .name = "enable", + .callback = events_callback, + }, + { + .name = "header_page", + .callback = events_callback, + }, + { + .name = "header_event", + .callback = events_callback, + }, + }; entry = trace_create_file("set_event", TRACE_MODE_WRITE, parent, tr, &ftrace_set_event_fops); if (!entry) return -ENOMEM; - d_events = eventfs_create_events_dir("events", parent); - if (IS_ERR(d_events)) { + nr_entries = ARRAY_SIZE(events_entries); + + e_events = eventfs_create_events_dir("events", parent, events_entries, + nr_entries, tr); + if (IS_ERR(e_events)) { pr_warn("Could not create tracefs 'events' directory\n"); return -ENOMEM; } - error = eventfs_add_events_file("enable", TRACE_MODE_WRITE, d_events, - tr, &ftrace_tr_enable_fops); - if (error) - return -ENOMEM; - /* There are not as crucial, just warn if they are not created */ trace_create_file("set_event_pid", TRACE_MODE_WRITE, parent, @@ -3677,16 +3811,7 @@ create_event_toplevel_files(struct dentry *parent, struct trace_array *tr) TRACE_MODE_WRITE, parent, tr, &ftrace_set_event_notrace_pid_fops); - /* ring buffer internal formats */ - eventfs_add_events_file("header_page", TRACE_MODE_READ, d_events, - ring_buffer_print_page_header, - &ftrace_show_header_fops); - - eventfs_add_events_file("header_event", TRACE_MODE_READ, d_events, - ring_buffer_print_entry_header, - &ftrace_show_header_fops); - - tr->event_dir = d_events; + tr->event_dir = e_events; return 0; } diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 68aaf0bd7a..5ecf3c8bde 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -774,23 +774,16 @@ static void last_cmd_set(struct trace_event_file *file, char *str) { const char *system = NULL, *name = NULL; struct trace_event_call *call; - int len; if (!str) return; - /* sizeof() contains the nul byte */ - len = sizeof(HIST_PREFIX) + strlen(str); kfree(last_cmd); - last_cmd = kzalloc(len, GFP_KERNEL); + + last_cmd = kasprintf(GFP_KERNEL, HIST_PREFIX "%s", str); if (!last_cmd) return; - strcpy(last_cmd, HIST_PREFIX); - /* Again, sizeof() contains the nul byte */ - len -= sizeof(HIST_PREFIX); - strncat(last_cmd, str, len); - if (file) { call = file->event_call; system = call->class->system; diff --git a/kernel/trace/trace_events_synth.c b/kernel/trace/trace_events_synth.c index 846e02c0fb..c82b401a29 100644 --- a/kernel/trace/trace_events_synth.c +++ b/kernel/trace/trace_events_synth.c @@ -441,8 +441,9 @@ static unsigned int trace_string(struct synth_trace_event *entry, if (is_dynamic) { union trace_synth_field *data = &entry->fields[*n_u64]; + len = fetch_store_strlen((unsigned long)str_val); data->as_dynamic.offset = struct_size(entry, fields, event->n_u64) + data_size; - data->as_dynamic.len = fetch_store_strlen((unsigned long)str_val); + data->as_dynamic.len = len; ret = fetch_store_string((unsigned long)str_val, &entry->fields[*n_u64], entry); @@ -1137,7 +1138,7 @@ EXPORT_SYMBOL_GPL(synth_event_add_fields); * @cmd: A pointer to the dynevent_cmd struct representing the new event * @name: The name of the synthetic event * @mod: The module creating the event, NULL if not created from a module - * @args: Variable number of arg (pairs), one pair for each field + * @...: Variable number of arg (pairs), one pair for each field * * NOTE: Users normally won't want to call this function directly, but * rather use the synth_event_gen_cmd_start() wrapper, which @@ -1695,7 +1696,7 @@ __synth_event_trace_end(struct synth_event_trace_state *trace_state) * synth_event_trace - Trace a synthetic event * @file: The trace_event_file representing the synthetic event * @n_vals: The number of values in vals - * @args: Variable number of args containing the event values + * @...: Variable number of args containing the event values * * Trace a synthetic event using the values passed in the variable * argument list. diff --git a/kernel/trace/trace_events_trigger.c b/kernel/trace/trace_events_trigger.c index 46439e3bce..b33c3861fb 100644 --- a/kernel/trace/trace_events_trigger.c +++ b/kernel/trace/trace_events_trigger.c @@ -1470,8 +1470,10 @@ register_snapshot_trigger(char *glob, struct event_trigger_data *data, struct trace_event_file *file) { - if (tracing_alloc_snapshot_instance(file->tr) != 0) - return 0; + int ret = tracing_alloc_snapshot_instance(file->tr); + + if (ret < 0) + return ret; return register_trigger(glob, data, file); } diff --git a/kernel/trace/trace_events_user.c b/kernel/trace/trace_events_user.c index b87f41187c..9365ce4074 100644 --- a/kernel/trace/trace_events_user.c +++ b/kernel/trace/trace_events_user.c @@ -50,18 +50,6 @@ #define EVENT_STATUS_OTHER BIT(7) /* - * User register flags are not allowed yet, keep them here until we are - * ready to expose them out to the user ABI. - */ -enum user_reg_flag { - /* Event will not delete upon last reference closing */ - USER_EVENT_REG_PERSIST = 1U << 0, - - /* This value or above is currently non-ABI */ - USER_EVENT_REG_MAX = 1U << 1, -}; - -/* * Stores the system name, tables, and locks for a group of events. This * allows isolation for events by various means. */ @@ -220,6 +208,17 @@ static u32 user_event_key(char *name) return jhash(name, strlen(name), 0); } +static bool user_event_capable(u16 reg_flags) +{ + /* Persistent events require CAP_PERFMON / CAP_SYS_ADMIN */ + if (reg_flags & USER_EVENT_REG_PERSIST) { + if (!perfmon_capable()) + return false; + } + + return true; +} + static struct user_event *user_event_get(struct user_event *user) { refcount_inc(&user->refcnt); @@ -1811,6 +1810,9 @@ static int user_event_free(struct dyn_event *ev) if (!user_event_last_ref(user)) return -EBUSY; + if (!user_event_capable(user->reg_flags)) + return -EPERM; + return destroy_user_event(user); } @@ -1926,10 +1928,13 @@ static int user_event_parse(struct user_event_group *group, char *name, int argc = 0; char **argv; - /* User register flags are not ready yet */ - if (reg_flags != 0 || flags != NULL) + /* Currently don't support any text based flags */ + if (flags != NULL) return -EINVAL; + if (!user_event_capable(reg_flags)) + return -EPERM; + /* Prevent dyn_event from racing */ mutex_lock(&event_mutex); user = find_user_event(group, name, &key); @@ -2062,6 +2067,9 @@ static int delete_user_event(struct user_event_group *group, char *name) if (!user_event_last_ref(user)) return -EBUSY; + if (!user_event_capable(user->reg_flags)) + return -EPERM; + return destroy_user_event(user); } diff --git a/kernel/trace/trace_kprobe.c b/kernel/trace/trace_kprobe.c index 47812aa16b..52f8b537dd 100644 --- a/kernel/trace/trace_kprobe.c +++ b/kernel/trace/trace_kprobe.c @@ -1249,6 +1249,12 @@ static const struct file_operations kprobe_events_ops = { .write = probes_write, }; +static unsigned long trace_kprobe_missed(struct trace_kprobe *tk) +{ + return trace_kprobe_is_return(tk) ? + tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed; +} + /* Probes profiling interfaces */ static int probes_profile_seq_show(struct seq_file *m, void *v) { @@ -1260,8 +1266,7 @@ static int probes_profile_seq_show(struct seq_file *m, void *v) return 0; tk = to_trace_kprobe(ev); - nmissed = trace_kprobe_is_return(tk) ? - tk->rp.kp.nmissed + tk->rp.nmissed : tk->rp.kp.nmissed; + nmissed = trace_kprobe_missed(tk); seq_printf(m, " %-44s %15lu %15lu\n", trace_probe_name(&tk->tp), trace_kprobe_nhit(tk), @@ -1607,7 +1612,8 @@ NOKPROBE_SYMBOL(kretprobe_perf_func); int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, const char **symbol, u64 *probe_offset, - u64 *probe_addr, bool perf_type_tracepoint) + u64 *probe_addr, unsigned long *missed, + bool perf_type_tracepoint) { const char *pevent = trace_event_name(event->tp_event); const char *group = event->tp_event->class->system; @@ -1626,6 +1632,8 @@ int bpf_get_kprobe_info(const struct perf_event *event, u32 *fd_type, *probe_addr = kallsyms_show_value(current_cred()) ? (unsigned long)tk->rp.kp.addr : 0; *symbol = tk->symbol; + if (missed) + *missed = trace_kprobe_missed(tk); return 0; } #endif /* CONFIG_PERF_EVENTS */ diff --git a/kernel/trace/trace_osnoise.c b/kernel/trace/trace_osnoise.c index bd0d01d00f..a8e28f9b92 100644 --- a/kernel/trace/trace_osnoise.c +++ b/kernel/trace/trace_osnoise.c @@ -2444,6 +2444,9 @@ static int timerlat_fd_open(struct inode *inode, struct file *file) tlat = this_cpu_tmr_var(); tlat->count = 0; + hrtimer_init(&tlat->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); + tlat->timer.function = timerlat_irq; + migrate_enable(); return 0; }; @@ -2526,9 +2529,6 @@ timerlat_fd_read(struct file *file, char __user *ubuf, size_t count, tlat->tracing_thread = false; tlat->kthread = current; - hrtimer_init(&tlat->timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD); - tlat->timer.function = timerlat_irq; - /* Annotate now to drift new period */ tlat->abs_period = hrtimer_cb_get_time(&tlat->timer); diff --git a/kernel/trace/trace_output.c b/kernel/trace/trace_output.c index 3b7d3e9eb6..3e7fa44dc2 100644 --- a/kernel/trace/trace_output.c +++ b/kernel/trace/trace_output.c @@ -404,7 +404,7 @@ static int seq_print_user_ip(struct trace_seq *s, struct mm_struct *mm, vmstart = vma->vm_start; } if (file) { - ret = trace_seq_path(s, &file->f_path); + ret = trace_seq_path(s, file_user_path(file)); if (ret) trace_seq_printf(s, "[+0x%lx]", ip - vmstart); diff --git a/kernel/trace/trace_probe.c b/kernel/trace/trace_probe.c index 4dc74d73fc..34289f9c67 100644 --- a/kernel/trace/trace_probe.c +++ b/kernel/trace/trace_probe.c @@ -1159,9 +1159,12 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, if (!(ctx->flags & TPARG_FL_TEVENT) && (strcmp(arg, "$comm") == 0 || strcmp(arg, "$COMM") == 0 || strncmp(arg, "\\\"", 2) == 0)) { - /* The type of $comm must be "string", and not an array. */ - if (parg->count || (t && strcmp(t, "string"))) + /* The type of $comm must be "string", and not an array type. */ + if (parg->count || (t && strcmp(t, "string"))) { + trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), + NEED_STRING_TYPE); goto out; + } parg->type = find_fetch_type("string", ctx->flags); } else parg->type = find_fetch_type(t, ctx->flags); @@ -1169,18 +1172,6 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, trace_probe_log_err(ctx->offset + (t ? (t - arg) : 0), BAD_TYPE); goto out; } - parg->offset = *size; - *size += parg->type->size * (parg->count ?: 1); - - ret = -ENOMEM; - if (parg->count) { - len = strlen(parg->type->fmttype) + 6; - parg->fmt = kmalloc(len, GFP_KERNEL); - if (!parg->fmt) - goto out; - snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype, - parg->count); - } code = tmp = kcalloc(FETCH_INSN_MAX, sizeof(*code), GFP_KERNEL); if (!code) @@ -1204,6 +1195,19 @@ static int traceprobe_parse_probe_arg_body(const char *argv, ssize_t *size, goto fail; } } + parg->offset = *size; + *size += parg->type->size * (parg->count ?: 1); + + if (parg->count) { + len = strlen(parg->type->fmttype) + 6; + parg->fmt = kmalloc(len, GFP_KERNEL); + if (!parg->fmt) { + ret = -ENOMEM; + goto out; + } + snprintf(parg->fmt, len, "%s[%d]", parg->type->fmttype, + parg->count); + } ret = -EINVAL; /* Store operation */ diff --git a/kernel/trace/trace_probe.h b/kernel/trace/trace_probe.h index 850d9ecb67..c1877d0182 100644 --- a/kernel/trace/trace_probe.h +++ b/kernel/trace/trace_probe.h @@ -515,7 +515,8 @@ extern int traceprobe_define_arg_fields(struct trace_event_call *event_call, C(BAD_HYPHEN, "Failed to parse single hyphen. Forgot '>'?"), \ C(NO_BTF_FIELD, "This field is not found."), \ C(BAD_BTF_TID, "Failed to get BTF type info."),\ - C(BAD_TYPE4STR, "This type does not fit for string."), + C(BAD_TYPE4STR, "This type does not fit for string."),\ + C(NEED_STRING_TYPE, "$comm and immediate-string only accepts string type"), #undef C #define C(a, b) TP_ERR_##a diff --git a/kernel/trace/trace_seq.c b/kernel/trace/trace_seq.c index bac06ee3b9..7be97229dd 100644 --- a/kernel/trace/trace_seq.c +++ b/kernel/trace/trace_seq.c @@ -370,8 +370,12 @@ EXPORT_SYMBOL_GPL(trace_seq_path); */ int trace_seq_to_user(struct trace_seq *s, char __user *ubuf, int cnt) { + int ret; __trace_seq_init(s); - return seq_buf_to_user(&s->seq, ubuf, cnt); + ret = seq_buf_to_user(&s->seq, ubuf, s->readpos, cnt); + if (ret > 0) + s->readpos += ret; + return ret; } EXPORT_SYMBOL_GPL(trace_seq_to_user); diff --git a/kernel/trace/trace_syscalls.c b/kernel/trace/trace_syscalls.c index de753403cd..9c581d6da8 100644 --- a/kernel/trace/trace_syscalls.c +++ b/kernel/trace/trace_syscalls.c @@ -556,7 +556,7 @@ static int perf_call_bpf_enter(struct trace_event_call *call, struct pt_regs *re { struct syscall_tp_t { struct trace_entry ent; - unsigned long syscall_nr; + int syscall_nr; unsigned long args[SYSCALL_DEFINE_MAXARGS]; } __aligned(8) param; int i; @@ -661,7 +661,7 @@ static int perf_call_bpf_exit(struct trace_event_call *call, struct pt_regs *reg { struct syscall_tp_t { struct trace_entry ent; - unsigned long syscall_nr; + int syscall_nr; unsigned long ret; } __aligned(8) param; diff --git a/kernel/up.c b/kernel/up.c index a38b8b0952..df50828cc2 100644 --- a/kernel/up.c +++ b/kernel/up.c @@ -25,7 +25,7 @@ int smp_call_function_single(int cpu, void (*func) (void *info), void *info, } EXPORT_SYMBOL(smp_call_function_single); -int smp_call_function_single_async(int cpu, struct __call_single_data *csd) +int smp_call_function_single_async(int cpu, call_single_data_t *csd) { unsigned long flags; diff --git a/kernel/user.c b/kernel/user.c index d667debeaf..03cedc366d 100644 --- a/kernel/user.c +++ b/kernel/user.c @@ -18,8 +18,18 @@ #include <linux/interrupt.h> #include <linux/export.h> #include <linux/user_namespace.h> +#include <linux/binfmts.h> #include <linux/proc_ns.h> +#if IS_ENABLED(CONFIG_BINFMT_MISC) +struct binfmt_misc init_binfmt_misc = { + .entries = LIST_HEAD_INIT(init_binfmt_misc.entries), + .enabled = true, + .entries_lock = __RW_LOCK_UNLOCKED(init_binfmt_misc.entries_lock), +}; +EXPORT_SYMBOL_GPL(init_binfmt_misc); +#endif + /* * userns count is 1 for root user, 1 for init_uts_ns, * and 1 for... ? @@ -67,6 +77,9 @@ struct user_namespace init_user_ns = { .keyring_name_list = LIST_HEAD_INIT(init_user_ns.keyring_name_list), .keyring_sem = __RWSEM_INITIALIZER(init_user_ns.keyring_sem), #endif +#if IS_ENABLED(CONFIG_BINFMT_MISC) + .binfmt_misc = &init_binfmt_misc, +#endif }; EXPORT_SYMBOL_GPL(init_user_ns); diff --git a/kernel/user_namespace.c b/kernel/user_namespace.c index 1d8e47bed3..eabe8bcc70 100644 --- a/kernel/user_namespace.c +++ b/kernel/user_namespace.c @@ -22,7 +22,7 @@ #include <linux/bsearch.h> #include <linux/sort.h> -static struct kmem_cache *user_ns_cachep __read_mostly; +static struct kmem_cache *user_ns_cachep __ro_after_init; static DEFINE_MUTEX(userns_state_mutex); static bool new_idmap_permitted(const struct file *file, @@ -213,6 +213,9 @@ static void free_user_ns(struct work_struct *work) kfree(ns->projid_map.forward); kfree(ns->projid_map.reverse); } +#if IS_ENABLED(CONFIG_BINFMT_MISC) + kfree(ns->binfmt_misc); +#endif retire_userns_sysctls(ns); key_free_user_ns(ns); ns_free_inum(&ns->ns); diff --git a/kernel/workqueue.c b/kernel/workqueue.c index e6a95bb74e..4f87b1851c 100644 --- a/kernel/workqueue.c +++ b/kernel/workqueue.c @@ -418,21 +418,21 @@ static struct workqueue_attrs *ordered_wq_attrs[NR_STD_WORKER_POOLS]; * process context while holding a pool lock. Bounce to a dedicated kthread * worker to avoid A-A deadlocks. */ -static struct kthread_worker *pwq_release_worker; +static struct kthread_worker *pwq_release_worker __ro_after_init; -struct workqueue_struct *system_wq __read_mostly; +struct workqueue_struct *system_wq __ro_after_init; EXPORT_SYMBOL(system_wq); -struct workqueue_struct *system_highpri_wq __read_mostly; +struct workqueue_struct *system_highpri_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_highpri_wq); -struct workqueue_struct *system_long_wq __read_mostly; +struct workqueue_struct *system_long_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_long_wq); -struct workqueue_struct *system_unbound_wq __read_mostly; +struct workqueue_struct *system_unbound_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_unbound_wq); -struct workqueue_struct *system_freezable_wq __read_mostly; +struct workqueue_struct *system_freezable_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_freezable_wq); -struct workqueue_struct *system_power_efficient_wq __read_mostly; +struct workqueue_struct *system_power_efficient_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_power_efficient_wq); -struct workqueue_struct *system_freezable_power_efficient_wq __read_mostly; +struct workqueue_struct *system_freezable_power_efficient_wq __ro_after_init; EXPORT_SYMBOL_GPL(system_freezable_power_efficient_wq); static int worker_thread(void *__worker); @@ -5793,13 +5793,9 @@ static int workqueue_apply_unbound_cpumask(const cpumask_var_t unbound_cpumask) list_for_each_entry(wq, &workqueues, list) { if (!(wq->flags & WQ_UNBOUND)) continue; - /* creating multiple pwqs breaks ordering guarantee */ - if (!list_empty(&wq->pwqs)) { - if (wq->flags & __WQ_ORDERED_EXPLICIT) - continue; - wq->flags &= ~__WQ_ORDERED; - } + if (wq->flags & __WQ_ORDERED) + continue; ctx = apply_wqattrs_prepare(wq, wq->unbound_attrs, unbound_cpumask); if (IS_ERR(ctx)) { |