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-rw-r--r--fs/proc/array.c65
-rw-r--r--fs/proc/base.c56
-rw-r--r--fs/proc/bootconfig.c6
-rw-r--r--fs/proc/fd.c11
-rw-r--r--fs/proc/inode.c13
-rw-r--r--fs/proc/kcore.c3
-rw-r--r--fs/proc/nommu.c2
-rw-r--r--fs/proc/proc_sysctl.c11
-rw-r--r--fs/proc/root.c2
-rw-r--r--fs/proc/self.c2
-rw-r--r--fs/proc/task_mmu.c766
-rw-r--r--fs/proc/task_nommu.c2
-rw-r--r--fs/proc/thread_self.c2
13 files changed, 855 insertions, 86 deletions
diff --git a/fs/proc/array.c b/fs/proc/array.c
index 2c2efbe685..34a47fb0c5 100644
--- a/fs/proc/array.c
+++ b/fs/proc/array.c
@@ -477,13 +477,13 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
int permitted;
struct mm_struct *mm;
unsigned long long start_time;
- unsigned long cmin_flt = 0, cmaj_flt = 0;
- unsigned long min_flt = 0, maj_flt = 0;
- u64 cutime, cstime, utime, stime;
- u64 cgtime, gtime;
+ unsigned long cmin_flt, cmaj_flt, min_flt, maj_flt;
+ u64 cutime, cstime, cgtime, utime, stime, gtime;
unsigned long rsslim = 0;
unsigned long flags;
int exit_code = task->exit_code;
+ struct signal_struct *sig = task->signal;
+ unsigned int seq = 1;
state = *get_task_state(task);
vsize = eip = esp = 0;
@@ -511,12 +511,8 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
sigemptyset(&sigign);
sigemptyset(&sigcatch);
- cutime = cstime = utime = stime = 0;
- cgtime = gtime = 0;
if (lock_task_sighand(task, &flags)) {
- struct signal_struct *sig = task->signal;
-
if (sig->tty) {
struct pid *pgrp = tty_get_pgrp(sig->tty);
tty_pgrp = pid_nr_ns(pgrp, ns);
@@ -527,27 +523,9 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
num_threads = get_nr_threads(task);
collect_sigign_sigcatch(task, &sigign, &sigcatch);
- cmin_flt = sig->cmin_flt;
- cmaj_flt = sig->cmaj_flt;
- cutime = sig->cutime;
- cstime = sig->cstime;
- cgtime = sig->cgtime;
rsslim = READ_ONCE(sig->rlim[RLIMIT_RSS].rlim_cur);
- /* add up live thread stats at the group level */
if (whole) {
- struct task_struct *t = task;
- do {
- min_flt += t->min_flt;
- maj_flt += t->maj_flt;
- gtime += task_gtime(t);
- } while_each_thread(task, t);
-
- min_flt += sig->min_flt;
- maj_flt += sig->maj_flt;
- thread_group_cputime_adjusted(task, &utime, &stime);
- gtime += sig->gtime;
-
if (sig->flags & (SIGNAL_GROUP_EXIT | SIGNAL_STOP_STOPPED))
exit_code = sig->group_exit_code;
}
@@ -561,10 +539,41 @@ static int do_task_stat(struct seq_file *m, struct pid_namespace *ns,
if (permitted && (!whole || num_threads < 2))
wchan = !task_is_running(task);
- if (!whole) {
+
+ do {
+ seq++; /* 2 on the 1st/lockless path, otherwise odd */
+ flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
+
+ cmin_flt = sig->cmin_flt;
+ cmaj_flt = sig->cmaj_flt;
+ cutime = sig->cutime;
+ cstime = sig->cstime;
+ cgtime = sig->cgtime;
+
+ if (whole) {
+ struct task_struct *t;
+
+ min_flt = sig->min_flt;
+ maj_flt = sig->maj_flt;
+ gtime = sig->gtime;
+
+ rcu_read_lock();
+ __for_each_thread(sig, t) {
+ min_flt += t->min_flt;
+ maj_flt += t->maj_flt;
+ gtime += task_gtime(t);
+ }
+ rcu_read_unlock();
+ }
+ } while (need_seqretry(&sig->stats_lock, seq));
+ done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
+
+ if (whole) {
+ thread_group_cputime_adjusted(task, &utime, &stime);
+ } else {
+ task_cputime_adjusted(task, &utime, &stime);
min_flt = task->min_flt;
maj_flt = task->maj_flt;
- task_cputime_adjusted(task, &utime, &stime);
gtime = task_gtime(task);
}
diff --git a/fs/proc/base.c b/fs/proc/base.c
index ffd54617c3..dd31e3b6bf 100644
--- a/fs/proc/base.c
+++ b/fs/proc/base.c
@@ -1153,11 +1153,10 @@ err_unlock:
static ssize_t oom_adj_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- char buffer[PROC_NUMBUF];
+ char buffer[PROC_NUMBUF] = {};
int oom_adj;
int err;
- memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count)) {
@@ -1213,11 +1212,10 @@ static ssize_t oom_score_adj_read(struct file *file, char __user *buf,
static ssize_t oom_score_adj_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- char buffer[PROC_NUMBUF];
+ char buffer[PROC_NUMBUF] = {};
int oom_score_adj;
int err;
- memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count)) {
@@ -1358,13 +1356,13 @@ static ssize_t proc_fault_inject_write(struct file * file,
const char __user * buf, size_t count, loff_t *ppos)
{
struct task_struct *task;
- char buffer[PROC_NUMBUF];
+ char buffer[PROC_NUMBUF] = {};
int make_it_fail;
int rv;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
- memset(buffer, 0, sizeof(buffer));
+
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count))
@@ -1509,11 +1507,10 @@ sched_autogroup_write(struct file *file, const char __user *buf,
{
struct inode *inode = file_inode(file);
struct task_struct *p;
- char buffer[PROC_NUMBUF];
+ char buffer[PROC_NUMBUF] = {};
int nice;
int err;
- memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count))
@@ -1666,10 +1663,9 @@ static ssize_t comm_write(struct file *file, const char __user *buf,
{
struct inode *inode = file_inode(file);
struct task_struct *p;
- char buffer[TASK_COMM_LEN];
+ char buffer[TASK_COMM_LEN] = {};
const size_t maxlen = sizeof(buffer) - 1;
- memset(buffer, 0, sizeof(buffer));
if (copy_from_user(buffer, buf, count > maxlen ? maxlen : count))
return -EFAULT;
@@ -1902,7 +1898,7 @@ struct inode *proc_pid_make_inode(struct super_block *sb,
ei = PROC_I(inode);
inode->i_mode = mode;
inode->i_ino = get_next_ino();
- inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+ simple_inode_init_ts(inode);
inode->i_op = &proc_def_inode_operations;
/*
@@ -2218,7 +2214,7 @@ static int map_files_get_link(struct dentry *dentry, struct path *path)
rc = -ENOENT;
vma = find_exact_vma(mm, vm_start, vm_end);
if (vma && vma->vm_file) {
- *path = vma->vm_file->f_path;
+ *path = *file_user_path(vma->vm_file);
path_get(path);
rc = 0;
}
@@ -2976,8 +2972,7 @@ static const struct file_operations proc_coredump_filter_operations = {
#ifdef CONFIG_TASK_IO_ACCOUNTING
static int do_io_accounting(struct task_struct *task, struct seq_file *m, int whole)
{
- struct task_io_accounting acct = task->ioac;
- unsigned long flags;
+ struct task_io_accounting acct;
int result;
result = down_read_killable(&task->signal->exec_update_lock);
@@ -2989,15 +2984,28 @@ static int do_io_accounting(struct task_struct *task, struct seq_file *m, int wh
goto out_unlock;
}
- if (whole && lock_task_sighand(task, &flags)) {
- struct task_struct *t = task;
+ if (whole) {
+ struct signal_struct *sig = task->signal;
+ struct task_struct *t;
+ unsigned int seq = 1;
+ unsigned long flags;
+
+ rcu_read_lock();
+ do {
+ seq++; /* 2 on the 1st/lockless path, otherwise odd */
+ flags = read_seqbegin_or_lock_irqsave(&sig->stats_lock, &seq);
- task_io_accounting_add(&acct, &task->signal->ioac);
- while_each_thread(task, t)
- task_io_accounting_add(&acct, &t->ioac);
+ acct = sig->ioac;
+ __for_each_thread(sig, t)
+ task_io_accounting_add(&acct, &t->ioac);
- unlock_task_sighand(task, &flags);
+ } while (need_seqretry(&sig->stats_lock, seq));
+ done_seqretry_irqrestore(&sig->stats_lock, seq, flags);
+ rcu_read_unlock();
+ } else {
+ acct = task->ioac;
}
+
seq_printf(m,
"rchar: %llu\n"
"wchar: %llu\n"
@@ -3818,7 +3826,7 @@ static struct task_struct *first_tid(struct pid *pid, int tid, loff_t f_pos,
for_each_thread(task, pos) {
if (!nr--)
goto found;
- };
+ }
fail:
pos = NULL;
goto out;
@@ -3840,10 +3848,8 @@ static struct task_struct *next_tid(struct task_struct *start)
struct task_struct *pos = NULL;
rcu_read_lock();
if (pid_alive(start)) {
- pos = next_thread(start);
- if (thread_group_leader(pos))
- pos = NULL;
- else
+ pos = __next_thread(start);
+ if (pos)
get_task_struct(pos);
}
rcu_read_unlock();
diff --git a/fs/proc/bootconfig.c b/fs/proc/bootconfig.c
index 2e244ada1f..902b326e1e 100644
--- a/fs/proc/bootconfig.c
+++ b/fs/proc/bootconfig.c
@@ -62,6 +62,12 @@ static int __init copy_xbc_key_value_list(char *dst, size_t size)
break;
dst += ret;
}
+ if (ret >= 0 && boot_command_line[0]) {
+ ret = snprintf(dst, rest(dst, end), "# Parameters from bootloader:\n# %s\n",
+ boot_command_line);
+ if (ret > 0)
+ dst += ret;
+ }
}
out:
kfree(key);
diff --git a/fs/proc/fd.c b/fs/proc/fd.c
index 6276b39388..6e72e5ad42 100644
--- a/fs/proc/fd.c
+++ b/fs/proc/fd.c
@@ -113,10 +113,12 @@ static bool tid_fd_mode(struct task_struct *task, unsigned fd, fmode_t *mode)
struct file *file;
rcu_read_lock();
- file = task_lookup_fd_rcu(task, fd);
- if (file)
- *mode = file->f_mode;
+ file = task_lookup_fdget_rcu(task, fd);
rcu_read_unlock();
+ if (file) {
+ *mode = file->f_mode;
+ fput(file);
+ }
return !!file;
}
@@ -259,12 +261,13 @@ static int proc_readfd_common(struct file *file, struct dir_context *ctx,
char name[10 + 1];
unsigned int len;
- f = task_lookup_next_fd_rcu(p, &fd);
+ f = task_lookup_next_fdget_rcu(p, &fd);
ctx->pos = fd + 2LL;
if (!f)
break;
data.mode = f->f_mode;
rcu_read_unlock();
+ fput(f);
data.fd = fd;
len = snprintf(name, sizeof(name), "%u", fd);
diff --git a/fs/proc/inode.c b/fs/proc/inode.c
index 532dc9d240..b33e490e3f 100644
--- a/fs/proc/inode.c
+++ b/fs/proc/inode.c
@@ -110,18 +110,15 @@ void __init proc_init_kmemcache(void)
void proc_invalidate_siblings_dcache(struct hlist_head *inodes, spinlock_t *lock)
{
- struct inode *inode;
- struct proc_inode *ei;
struct hlist_node *node;
struct super_block *old_sb = NULL;
rcu_read_lock();
- for (;;) {
+ while ((node = hlist_first_rcu(inodes))) {
+ struct proc_inode *ei = hlist_entry(node, struct proc_inode, sibling_inodes);
struct super_block *sb;
- node = hlist_first_rcu(inodes);
- if (!node)
- break;
- ei = hlist_entry(node, struct proc_inode, sibling_inodes);
+ struct inode *inode;
+
spin_lock(lock);
hlist_del_init_rcu(&ei->sibling_inodes);
spin_unlock(lock);
@@ -660,7 +657,7 @@ struct inode *proc_get_inode(struct super_block *sb, struct proc_dir_entry *de)
inode->i_private = de->data;
inode->i_ino = de->low_ino;
- inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+ simple_inode_init_ts(inode);
PROC_I(inode)->pde = de;
if (is_empty_pde(de)) {
make_empty_dir_inode(inode);
diff --git a/fs/proc/kcore.c b/fs/proc/kcore.c
index 23fc24d16b..6422e569b0 100644
--- a/fs/proc/kcore.c
+++ b/fs/proc/kcore.c
@@ -546,7 +546,8 @@ static ssize_t read_kcore_iter(struct kiocb *iocb, struct iov_iter *iter)
* and explicitly excluded physical ranges.
*/
if (!page || PageOffline(page) ||
- is_page_hwpoison(page) || !pfn_is_ram(pfn)) {
+ is_page_hwpoison(page) || !pfn_is_ram(pfn) ||
+ pfn_is_unaccepted_memory(pfn)) {
if (iov_iter_zero(tsz, iter) != tsz) {
ret = -EFAULT;
goto out;
diff --git a/fs/proc/nommu.c b/fs/proc/nommu.c
index 4d34935794..c6e7ebc637 100644
--- a/fs/proc/nommu.c
+++ b/fs/proc/nommu.c
@@ -58,7 +58,7 @@ static int nommu_region_show(struct seq_file *m, struct vm_region *region)
if (file) {
seq_pad(m, ' ');
- seq_file_path(m, file, "");
+ seq_path(m, file_user_path(file), "");
}
seq_putc(m, '\n');
diff --git a/fs/proc/proc_sysctl.c b/fs/proc/proc_sysctl.c
index de484195f4..84abf98340 100644
--- a/fs/proc/proc_sysctl.c
+++ b/fs/proc/proc_sysctl.c
@@ -44,7 +44,7 @@ static struct ctl_table sysctl_mount_point[] = {
*/
struct ctl_table_header *register_sysctl_mount_point(const char *path)
{
- return register_sysctl_sz(path, sysctl_mount_point, 0);
+ return register_sysctl(path, sysctl_mount_point);
}
EXPORT_SYMBOL(register_sysctl_mount_point);
@@ -233,7 +233,8 @@ static int insert_header(struct ctl_dir *dir, struct ctl_table_header *header)
return -EROFS;
/* Am I creating a permanently empty directory? */
- if (sysctl_is_perm_empty_ctl_table(header->ctl_table)) {
+ if (header->ctl_table_size > 0 &&
+ sysctl_is_perm_empty_ctl_table(header->ctl_table)) {
if (!RB_EMPTY_ROOT(&dir->root))
return -EINVAL;
sysctl_set_perm_empty_ctl_header(dir_h);
@@ -465,7 +466,7 @@ static struct inode *proc_sys_make_inode(struct super_block *sb,
head->count++;
spin_unlock(&sysctl_lock);
- inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+ simple_inode_init_ts(inode);
inode->i_mode = table->mode;
if (!S_ISDIR(table->mode)) {
inode->i_mode |= S_IFREG;
@@ -1213,6 +1214,10 @@ static bool get_links(struct ctl_dir *dir,
struct ctl_table_header *tmp_head;
struct ctl_table *entry, *link;
+ if (header->ctl_table_size == 0 ||
+ sysctl_is_perm_empty_ctl_table(header->ctl_table))
+ return true;
+
/* Are there links available for every entry in table? */
list_for_each_table_entry(entry, header) {
const char *procname = entry->procname;
diff --git a/fs/proc/root.c b/fs/proc/root.c
index 9191248f2d..b55dbc7028 100644
--- a/fs/proc/root.c
+++ b/fs/proc/root.c
@@ -188,7 +188,7 @@ static int proc_fill_super(struct super_block *s, struct fs_context *fc)
s->s_stack_depth = FILESYSTEM_MAX_STACK_DEPTH;
/* procfs dentries and inodes don't require IO to create */
- s->s_shrink.seeks = 0;
+ s->s_shrink->seeks = 0;
pde_get(&proc_root);
root_inode = proc_get_inode(s, &proc_root);
diff --git a/fs/proc/self.c b/fs/proc/self.c
index ecc4da8d26..b46fbfd226 100644
--- a/fs/proc/self.c
+++ b/fs/proc/self.c
@@ -46,7 +46,7 @@ int proc_setup_self(struct super_block *s)
struct inode *inode = new_inode(s);
if (inode) {
inode->i_ino = self_inum;
- inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+ simple_inode_init_ts(inode);
inode->i_mode = S_IFLNK | S_IRWXUGO;
inode->i_uid = GLOBAL_ROOT_UID;
inode->i_gid = GLOBAL_ROOT_GID;
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c
index 3dd5be9669..4905420d33 100644
--- a/fs/proc/task_mmu.c
+++ b/fs/proc/task_mmu.c
@@ -20,6 +20,8 @@
#include <linux/shmem_fs.h>
#include <linux/uaccess.h>
#include <linux/pkeys.h>
+#include <linux/minmax.h>
+#include <linux/overflow.h>
#include <asm/elf.h>
#include <asm/tlb.h>
@@ -296,7 +298,7 @@ show_map_vma(struct seq_file *m, struct vm_area_struct *vma)
if (anon_name)
seq_printf(m, "[anon_shmem:%s]", anon_name->name);
else
- seq_file_path(m, file, "\n");
+ seq_path(m, file_user_path(file), "\n");
goto done;
}
@@ -849,9 +851,7 @@ static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss,
static int show_smap(struct seq_file *m, void *v)
{
struct vm_area_struct *vma = v;
- struct mem_size_stats mss;
-
- memset(&mss, 0, sizeof(mss));
+ struct mem_size_stats mss = {};
smap_gather_stats(vma, &mss, 0);
@@ -877,7 +877,7 @@ static int show_smap(struct seq_file *m, void *v)
static int show_smaps_rollup(struct seq_file *m, void *v)
{
struct proc_maps_private *priv = m->private;
- struct mem_size_stats mss;
+ struct mem_size_stats mss = {};
struct mm_struct *mm = priv->mm;
struct vm_area_struct *vma;
unsigned long vma_start = 0, last_vma_end = 0;
@@ -893,8 +893,6 @@ static int show_smaps_rollup(struct seq_file *m, void *v)
goto out_put_task;
}
- memset(&mss, 0, sizeof(mss));
-
ret = mmap_read_lock_killable(mm);
if (ret)
goto out_put_mm;
@@ -1246,14 +1244,13 @@ static ssize_t clear_refs_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
struct task_struct *task;
- char buffer[PROC_NUMBUF];
+ char buffer[PROC_NUMBUF] = {};
struct mm_struct *mm;
struct vm_area_struct *vma;
enum clear_refs_types type;
int itype;
int rv;
- memset(buffer, 0, sizeof(buffer));
if (count > sizeof(buffer) - 1)
count = sizeof(buffer) - 1;
if (copy_from_user(buffer, buf, count))
@@ -1761,11 +1758,755 @@ static int pagemap_release(struct inode *inode, struct file *file)
return 0;
}
+#define PM_SCAN_CATEGORIES (PAGE_IS_WPALLOWED | PAGE_IS_WRITTEN | \
+ PAGE_IS_FILE | PAGE_IS_PRESENT | \
+ PAGE_IS_SWAPPED | PAGE_IS_PFNZERO | \
+ PAGE_IS_HUGE)
+#define PM_SCAN_FLAGS (PM_SCAN_WP_MATCHING | PM_SCAN_CHECK_WPASYNC)
+
+struct pagemap_scan_private {
+ struct pm_scan_arg arg;
+ unsigned long masks_of_interest, cur_vma_category;
+ struct page_region *vec_buf;
+ unsigned long vec_buf_len, vec_buf_index, found_pages;
+ struct page_region __user *vec_out;
+};
+
+static unsigned long pagemap_page_category(struct pagemap_scan_private *p,
+ struct vm_area_struct *vma,
+ unsigned long addr, pte_t pte)
+{
+ unsigned long categories = 0;
+
+ if (pte_present(pte)) {
+ struct page *page;
+
+ categories |= PAGE_IS_PRESENT;
+ if (!pte_uffd_wp(pte))
+ categories |= PAGE_IS_WRITTEN;
+
+ if (p->masks_of_interest & PAGE_IS_FILE) {
+ page = vm_normal_page(vma, addr, pte);
+ if (page && !PageAnon(page))
+ categories |= PAGE_IS_FILE;
+ }
+
+ if (is_zero_pfn(pte_pfn(pte)))
+ categories |= PAGE_IS_PFNZERO;
+ } else if (is_swap_pte(pte)) {
+ swp_entry_t swp;
+
+ categories |= PAGE_IS_SWAPPED;
+ if (!pte_swp_uffd_wp_any(pte))
+ categories |= PAGE_IS_WRITTEN;
+
+ if (p->masks_of_interest & PAGE_IS_FILE) {
+ swp = pte_to_swp_entry(pte);
+ if (is_pfn_swap_entry(swp) &&
+ !PageAnon(pfn_swap_entry_to_page(swp)))
+ categories |= PAGE_IS_FILE;
+ }
+ }
+
+ return categories;
+}
+
+static void make_uffd_wp_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *pte)
+{
+ pte_t ptent = ptep_get(pte);
+
+ if (pte_present(ptent)) {
+ pte_t old_pte;
+
+ old_pte = ptep_modify_prot_start(vma, addr, pte);
+ ptent = pte_mkuffd_wp(ptent);
+ ptep_modify_prot_commit(vma, addr, pte, old_pte, ptent);
+ } else if (is_swap_pte(ptent)) {
+ ptent = pte_swp_mkuffd_wp(ptent);
+ set_pte_at(vma->vm_mm, addr, pte, ptent);
+ } else {
+ set_pte_at(vma->vm_mm, addr, pte,
+ make_pte_marker(PTE_MARKER_UFFD_WP));
+ }
+}
+
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+static unsigned long pagemap_thp_category(struct pagemap_scan_private *p,
+ struct vm_area_struct *vma,
+ unsigned long addr, pmd_t pmd)
+{
+ unsigned long categories = PAGE_IS_HUGE;
+
+ if (pmd_present(pmd)) {
+ struct page *page;
+
+ categories |= PAGE_IS_PRESENT;
+ if (!pmd_uffd_wp(pmd))
+ categories |= PAGE_IS_WRITTEN;
+
+ if (p->masks_of_interest & PAGE_IS_FILE) {
+ page = vm_normal_page_pmd(vma, addr, pmd);
+ if (page && !PageAnon(page))
+ categories |= PAGE_IS_FILE;
+ }
+
+ if (is_zero_pfn(pmd_pfn(pmd)))
+ categories |= PAGE_IS_PFNZERO;
+ } else if (is_swap_pmd(pmd)) {
+ swp_entry_t swp;
+
+ categories |= PAGE_IS_SWAPPED;
+ if (!pmd_swp_uffd_wp(pmd))
+ categories |= PAGE_IS_WRITTEN;
+
+ if (p->masks_of_interest & PAGE_IS_FILE) {
+ swp = pmd_to_swp_entry(pmd);
+ if (is_pfn_swap_entry(swp) &&
+ !PageAnon(pfn_swap_entry_to_page(swp)))
+ categories |= PAGE_IS_FILE;
+ }
+ }
+
+ return categories;
+}
+
+static void make_uffd_wp_pmd(struct vm_area_struct *vma,
+ unsigned long addr, pmd_t *pmdp)
+{
+ pmd_t old, pmd = *pmdp;
+
+ if (pmd_present(pmd)) {
+ old = pmdp_invalidate_ad(vma, addr, pmdp);
+ pmd = pmd_mkuffd_wp(old);
+ set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
+ } else if (is_migration_entry(pmd_to_swp_entry(pmd))) {
+ pmd = pmd_swp_mkuffd_wp(pmd);
+ set_pmd_at(vma->vm_mm, addr, pmdp, pmd);
+ }
+}
+#endif /* CONFIG_TRANSPARENT_HUGEPAGE */
+
+#ifdef CONFIG_HUGETLB_PAGE
+static unsigned long pagemap_hugetlb_category(pte_t pte)
+{
+ unsigned long categories = PAGE_IS_HUGE;
+
+ /*
+ * According to pagemap_hugetlb_range(), file-backed HugeTLB
+ * page cannot be swapped. So PAGE_IS_FILE is not checked for
+ * swapped pages.
+ */
+ if (pte_present(pte)) {
+ categories |= PAGE_IS_PRESENT;
+ if (!huge_pte_uffd_wp(pte))
+ categories |= PAGE_IS_WRITTEN;
+ if (!PageAnon(pte_page(pte)))
+ categories |= PAGE_IS_FILE;
+ if (is_zero_pfn(pte_pfn(pte)))
+ categories |= PAGE_IS_PFNZERO;
+ } else if (is_swap_pte(pte)) {
+ categories |= PAGE_IS_SWAPPED;
+ if (!pte_swp_uffd_wp_any(pte))
+ categories |= PAGE_IS_WRITTEN;
+ }
+
+ return categories;
+}
+
+static void make_uffd_wp_huge_pte(struct vm_area_struct *vma,
+ unsigned long addr, pte_t *ptep,
+ pte_t ptent)
+{
+ unsigned long psize;
+
+ if (is_hugetlb_entry_hwpoisoned(ptent) || is_pte_marker(ptent))
+ return;
+
+ psize = huge_page_size(hstate_vma(vma));
+
+ if (is_hugetlb_entry_migration(ptent))
+ set_huge_pte_at(vma->vm_mm, addr, ptep,
+ pte_swp_mkuffd_wp(ptent), psize);
+ else if (!huge_pte_none(ptent))
+ huge_ptep_modify_prot_commit(vma, addr, ptep, ptent,
+ huge_pte_mkuffd_wp(ptent));
+ else
+ set_huge_pte_at(vma->vm_mm, addr, ptep,
+ make_pte_marker(PTE_MARKER_UFFD_WP), psize);
+}
+#endif /* CONFIG_HUGETLB_PAGE */
+
+#if defined(CONFIG_TRANSPARENT_HUGEPAGE) || defined(CONFIG_HUGETLB_PAGE)
+static void pagemap_scan_backout_range(struct pagemap_scan_private *p,
+ unsigned long addr, unsigned long end)
+{
+ struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index];
+
+ if (cur_buf->start != addr)
+ cur_buf->end = addr;
+ else
+ cur_buf->start = cur_buf->end = 0;
+
+ p->found_pages -= (end - addr) / PAGE_SIZE;
+}
+#endif
+
+static bool pagemap_scan_is_interesting_page(unsigned long categories,
+ const struct pagemap_scan_private *p)
+{
+ categories ^= p->arg.category_inverted;
+ if ((categories & p->arg.category_mask) != p->arg.category_mask)
+ return false;
+ if (p->arg.category_anyof_mask && !(categories & p->arg.category_anyof_mask))
+ return false;
+
+ return true;
+}
+
+static bool pagemap_scan_is_interesting_vma(unsigned long categories,
+ const struct pagemap_scan_private *p)
+{
+ unsigned long required = p->arg.category_mask & PAGE_IS_WPALLOWED;
+
+ categories ^= p->arg.category_inverted;
+ if ((categories & required) != required)
+ return false;
+
+ return true;
+}
+
+static int pagemap_scan_test_walk(unsigned long start, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct pagemap_scan_private *p = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ unsigned long vma_category = 0;
+ bool wp_allowed = userfaultfd_wp_async(vma) &&
+ userfaultfd_wp_use_markers(vma);
+
+ if (!wp_allowed) {
+ /* User requested explicit failure over wp-async capability */
+ if (p->arg.flags & PM_SCAN_CHECK_WPASYNC)
+ return -EPERM;
+ /*
+ * User requires wr-protect, and allows silently skipping
+ * unsupported vmas.
+ */
+ if (p->arg.flags & PM_SCAN_WP_MATCHING)
+ return 1;
+ /*
+ * Then the request doesn't involve wr-protects at all,
+ * fall through to the rest checks, and allow vma walk.
+ */
+ }
+
+ if (vma->vm_flags & VM_PFNMAP)
+ return 1;
+
+ if (wp_allowed)
+ vma_category |= PAGE_IS_WPALLOWED;
+
+ if (!pagemap_scan_is_interesting_vma(vma_category, p))
+ return 1;
+
+ p->cur_vma_category = vma_category;
+
+ return 0;
+}
+
+static bool pagemap_scan_push_range(unsigned long categories,
+ struct pagemap_scan_private *p,
+ unsigned long addr, unsigned long end)
+{
+ struct page_region *cur_buf = &p->vec_buf[p->vec_buf_index];
+
+ /*
+ * When there is no output buffer provided at all, the sentinel values
+ * won't match here. There is no other way for `cur_buf->end` to be
+ * non-zero other than it being non-empty.
+ */
+ if (addr == cur_buf->end && categories == cur_buf->categories) {
+ cur_buf->end = end;
+ return true;
+ }
+
+ if (cur_buf->end) {
+ if (p->vec_buf_index >= p->vec_buf_len - 1)
+ return false;
+
+ cur_buf = &p->vec_buf[++p->vec_buf_index];
+ }
+
+ cur_buf->start = addr;
+ cur_buf->end = end;
+ cur_buf->categories = categories;
+
+ return true;
+}
+
+static int pagemap_scan_output(unsigned long categories,
+ struct pagemap_scan_private *p,
+ unsigned long addr, unsigned long *end)
+{
+ unsigned long n_pages, total_pages;
+ int ret = 0;
+
+ if (!p->vec_buf)
+ return 0;
+
+ categories &= p->arg.return_mask;
+
+ n_pages = (*end - addr) / PAGE_SIZE;
+ if (check_add_overflow(p->found_pages, n_pages, &total_pages) ||
+ total_pages > p->arg.max_pages) {
+ size_t n_too_much = total_pages - p->arg.max_pages;
+ *end -= n_too_much * PAGE_SIZE;
+ n_pages -= n_too_much;
+ ret = -ENOSPC;
+ }
+
+ if (!pagemap_scan_push_range(categories, p, addr, *end)) {
+ *end = addr;
+ n_pages = 0;
+ ret = -ENOSPC;
+ }
+
+ p->found_pages += n_pages;
+ if (ret)
+ p->arg.walk_end = *end;
+
+ return ret;
+}
+
+static int pagemap_scan_thp_entry(pmd_t *pmd, unsigned long start,
+ unsigned long end, struct mm_walk *walk)
+{
+#ifdef CONFIG_TRANSPARENT_HUGEPAGE
+ struct pagemap_scan_private *p = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ unsigned long categories;
+ spinlock_t *ptl;
+ int ret = 0;
+
+ ptl = pmd_trans_huge_lock(pmd, vma);
+ if (!ptl)
+ return -ENOENT;
+
+ categories = p->cur_vma_category |
+ pagemap_thp_category(p, vma, start, *pmd);
+
+ if (!pagemap_scan_is_interesting_page(categories, p))
+ goto out_unlock;
+
+ ret = pagemap_scan_output(categories, p, start, &end);
+ if (start == end)
+ goto out_unlock;
+
+ if (~p->arg.flags & PM_SCAN_WP_MATCHING)
+ goto out_unlock;
+ if (~categories & PAGE_IS_WRITTEN)
+ goto out_unlock;
+
+ /*
+ * Break huge page into small pages if the WP operation
+ * needs to be performed on a portion of the huge page.
+ */
+ if (end != start + HPAGE_SIZE) {
+ spin_unlock(ptl);
+ split_huge_pmd(vma, pmd, start);
+ pagemap_scan_backout_range(p, start, end);
+ /* Report as if there was no THP */
+ return -ENOENT;
+ }
+
+ make_uffd_wp_pmd(vma, start, pmd);
+ flush_tlb_range(vma, start, end);
+out_unlock:
+ spin_unlock(ptl);
+ return ret;
+#else /* !CONFIG_TRANSPARENT_HUGEPAGE */
+ return -ENOENT;
+#endif
+}
+
+static int pagemap_scan_pmd_entry(pmd_t *pmd, unsigned long start,
+ unsigned long end, struct mm_walk *walk)
+{
+ struct pagemap_scan_private *p = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ unsigned long addr, flush_end = 0;
+ pte_t *pte, *start_pte;
+ spinlock_t *ptl;
+ int ret;
+
+ arch_enter_lazy_mmu_mode();
+
+ ret = pagemap_scan_thp_entry(pmd, start, end, walk);
+ if (ret != -ENOENT) {
+ arch_leave_lazy_mmu_mode();
+ return ret;
+ }
+
+ ret = 0;
+ start_pte = pte = pte_offset_map_lock(vma->vm_mm, pmd, start, &ptl);
+ if (!pte) {
+ arch_leave_lazy_mmu_mode();
+ walk->action = ACTION_AGAIN;
+ return 0;
+ }
+
+ if ((p->arg.flags & PM_SCAN_WP_MATCHING) && !p->vec_out) {
+ /* Fast path for performing exclusive WP */
+ for (addr = start; addr != end; pte++, addr += PAGE_SIZE) {
+ if (pte_uffd_wp(ptep_get(pte)))
+ continue;
+ make_uffd_wp_pte(vma, addr, pte);
+ if (!flush_end)
+ start = addr;
+ flush_end = addr + PAGE_SIZE;
+ }
+ goto flush_and_return;
+ }
+
+ if (!p->arg.category_anyof_mask && !p->arg.category_inverted &&
+ p->arg.category_mask == PAGE_IS_WRITTEN &&
+ p->arg.return_mask == PAGE_IS_WRITTEN) {
+ for (addr = start; addr < end; pte++, addr += PAGE_SIZE) {
+ unsigned long next = addr + PAGE_SIZE;
+
+ if (pte_uffd_wp(ptep_get(pte)))
+ continue;
+ ret = pagemap_scan_output(p->cur_vma_category | PAGE_IS_WRITTEN,
+ p, addr, &next);
+ if (next == addr)
+ break;
+ if (~p->arg.flags & PM_SCAN_WP_MATCHING)
+ continue;
+ make_uffd_wp_pte(vma, addr, pte);
+ if (!flush_end)
+ start = addr;
+ flush_end = next;
+ }
+ goto flush_and_return;
+ }
+
+ for (addr = start; addr != end; pte++, addr += PAGE_SIZE) {
+ unsigned long categories = p->cur_vma_category |
+ pagemap_page_category(p, vma, addr, ptep_get(pte));
+ unsigned long next = addr + PAGE_SIZE;
+
+ if (!pagemap_scan_is_interesting_page(categories, p))
+ continue;
+
+ ret = pagemap_scan_output(categories, p, addr, &next);
+ if (next == addr)
+ break;
+
+ if (~p->arg.flags & PM_SCAN_WP_MATCHING)
+ continue;
+ if (~categories & PAGE_IS_WRITTEN)
+ continue;
+
+ make_uffd_wp_pte(vma, addr, pte);
+ if (!flush_end)
+ start = addr;
+ flush_end = next;
+ }
+
+flush_and_return:
+ if (flush_end)
+ flush_tlb_range(vma, start, addr);
+
+ pte_unmap_unlock(start_pte, ptl);
+ arch_leave_lazy_mmu_mode();
+
+ cond_resched();
+ return ret;
+}
+
+#ifdef CONFIG_HUGETLB_PAGE
+static int pagemap_scan_hugetlb_entry(pte_t *ptep, unsigned long hmask,
+ unsigned long start, unsigned long end,
+ struct mm_walk *walk)
+{
+ struct pagemap_scan_private *p = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ unsigned long categories;
+ spinlock_t *ptl;
+ int ret = 0;
+ pte_t pte;
+
+ if (~p->arg.flags & PM_SCAN_WP_MATCHING) {
+ /* Go the short route when not write-protecting pages. */
+
+ pte = huge_ptep_get(ptep);
+ categories = p->cur_vma_category | pagemap_hugetlb_category(pte);
+
+ if (!pagemap_scan_is_interesting_page(categories, p))
+ return 0;
+
+ return pagemap_scan_output(categories, p, start, &end);
+ }
+
+ i_mmap_lock_write(vma->vm_file->f_mapping);
+ ptl = huge_pte_lock(hstate_vma(vma), vma->vm_mm, ptep);
+
+ pte = huge_ptep_get(ptep);
+ categories = p->cur_vma_category | pagemap_hugetlb_category(pte);
+
+ if (!pagemap_scan_is_interesting_page(categories, p))
+ goto out_unlock;
+
+ ret = pagemap_scan_output(categories, p, start, &end);
+ if (start == end)
+ goto out_unlock;
+
+ if (~categories & PAGE_IS_WRITTEN)
+ goto out_unlock;
+
+ if (end != start + HPAGE_SIZE) {
+ /* Partial HugeTLB page WP isn't possible. */
+ pagemap_scan_backout_range(p, start, end);
+ p->arg.walk_end = start;
+ ret = 0;
+ goto out_unlock;
+ }
+
+ make_uffd_wp_huge_pte(vma, start, ptep, pte);
+ flush_hugetlb_tlb_range(vma, start, end);
+
+out_unlock:
+ spin_unlock(ptl);
+ i_mmap_unlock_write(vma->vm_file->f_mapping);
+
+ return ret;
+}
+#else
+#define pagemap_scan_hugetlb_entry NULL
+#endif
+
+static int pagemap_scan_pte_hole(unsigned long addr, unsigned long end,
+ int depth, struct mm_walk *walk)
+{
+ struct pagemap_scan_private *p = walk->private;
+ struct vm_area_struct *vma = walk->vma;
+ int ret, err;
+
+ if (!vma || !pagemap_scan_is_interesting_page(p->cur_vma_category, p))
+ return 0;
+
+ ret = pagemap_scan_output(p->cur_vma_category, p, addr, &end);
+ if (addr == end)
+ return ret;
+
+ if (~p->arg.flags & PM_SCAN_WP_MATCHING)
+ return ret;
+
+ err = uffd_wp_range(vma, addr, end - addr, true);
+ if (err < 0)
+ ret = err;
+
+ return ret;
+}
+
+static const struct mm_walk_ops pagemap_scan_ops = {
+ .test_walk = pagemap_scan_test_walk,
+ .pmd_entry = pagemap_scan_pmd_entry,
+ .pte_hole = pagemap_scan_pte_hole,
+ .hugetlb_entry = pagemap_scan_hugetlb_entry,
+};
+
+static int pagemap_scan_get_args(struct pm_scan_arg *arg,
+ unsigned long uarg)
+{
+ if (copy_from_user(arg, (void __user *)uarg, sizeof(*arg)))
+ return -EFAULT;
+
+ if (arg->size != sizeof(struct pm_scan_arg))
+ return -EINVAL;
+
+ /* Validate requested features */
+ if (arg->flags & ~PM_SCAN_FLAGS)
+ return -EINVAL;
+ if ((arg->category_inverted | arg->category_mask |
+ arg->category_anyof_mask | arg->return_mask) & ~PM_SCAN_CATEGORIES)
+ return -EINVAL;
+
+ arg->start = untagged_addr((unsigned long)arg->start);
+ arg->end = untagged_addr((unsigned long)arg->end);
+ arg->vec = untagged_addr((unsigned long)arg->vec);
+
+ /* Validate memory pointers */
+ if (!IS_ALIGNED(arg->start, PAGE_SIZE))
+ return -EINVAL;
+ if (!access_ok((void __user *)(long)arg->start, arg->end - arg->start))
+ return -EFAULT;
+ if (!arg->vec && arg->vec_len)
+ return -EINVAL;
+ if (arg->vec && !access_ok((void __user *)(long)arg->vec,
+ arg->vec_len * sizeof(struct page_region)))
+ return -EFAULT;
+
+ /* Fixup default values */
+ arg->end = ALIGN(arg->end, PAGE_SIZE);
+ arg->walk_end = 0;
+ if (!arg->max_pages)
+ arg->max_pages = ULONG_MAX;
+
+ return 0;
+}
+
+static int pagemap_scan_writeback_args(struct pm_scan_arg *arg,
+ unsigned long uargl)
+{
+ struct pm_scan_arg __user *uarg = (void __user *)uargl;
+
+ if (copy_to_user(&uarg->walk_end, &arg->walk_end, sizeof(arg->walk_end)))
+ return -EFAULT;
+
+ return 0;
+}
+
+static int pagemap_scan_init_bounce_buffer(struct pagemap_scan_private *p)
+{
+ if (!p->arg.vec_len)
+ return 0;
+
+ p->vec_buf_len = min_t(size_t, PAGEMAP_WALK_SIZE >> PAGE_SHIFT,
+ p->arg.vec_len);
+ p->vec_buf = kmalloc_array(p->vec_buf_len, sizeof(*p->vec_buf),
+ GFP_KERNEL);
+ if (!p->vec_buf)
+ return -ENOMEM;
+
+ p->vec_buf->start = p->vec_buf->end = 0;
+ p->vec_out = (struct page_region __user *)(long)p->arg.vec;
+
+ return 0;
+}
+
+static long pagemap_scan_flush_buffer(struct pagemap_scan_private *p)
+{
+ const struct page_region *buf = p->vec_buf;
+ long n = p->vec_buf_index;
+
+ if (!p->vec_buf)
+ return 0;
+
+ if (buf[n].end != buf[n].start)
+ n++;
+
+ if (!n)
+ return 0;
+
+ if (copy_to_user(p->vec_out, buf, n * sizeof(*buf)))
+ return -EFAULT;
+
+ p->arg.vec_len -= n;
+ p->vec_out += n;
+
+ p->vec_buf_index = 0;
+ p->vec_buf_len = min_t(size_t, p->vec_buf_len, p->arg.vec_len);
+ p->vec_buf->start = p->vec_buf->end = 0;
+
+ return n;
+}
+
+static long do_pagemap_scan(struct mm_struct *mm, unsigned long uarg)
+{
+ struct pagemap_scan_private p = {0};
+ unsigned long walk_start;
+ size_t n_ranges_out = 0;
+ int ret;
+
+ ret = pagemap_scan_get_args(&p.arg, uarg);
+ if (ret)
+ return ret;
+
+ p.masks_of_interest = p.arg.category_mask | p.arg.category_anyof_mask |
+ p.arg.return_mask;
+ ret = pagemap_scan_init_bounce_buffer(&p);
+ if (ret)
+ return ret;
+
+ for (walk_start = p.arg.start; walk_start < p.arg.end;
+ walk_start = p.arg.walk_end) {
+ struct mmu_notifier_range range;
+ long n_out;
+
+ if (fatal_signal_pending(current)) {
+ ret = -EINTR;
+ break;
+ }
+
+ ret = mmap_read_lock_killable(mm);
+ if (ret)
+ break;
+
+ /* Protection change for the range is going to happen. */
+ if (p.arg.flags & PM_SCAN_WP_MATCHING) {
+ mmu_notifier_range_init(&range, MMU_NOTIFY_PROTECTION_VMA, 0,
+ mm, walk_start, p.arg.end);
+ mmu_notifier_invalidate_range_start(&range);
+ }
+
+ ret = walk_page_range(mm, walk_start, p.arg.end,
+ &pagemap_scan_ops, &p);
+
+ if (p.arg.flags & PM_SCAN_WP_MATCHING)
+ mmu_notifier_invalidate_range_end(&range);
+
+ mmap_read_unlock(mm);
+
+ n_out = pagemap_scan_flush_buffer(&p);
+ if (n_out < 0)
+ ret = n_out;
+ else
+ n_ranges_out += n_out;
+
+ if (ret != -ENOSPC)
+ break;
+
+ if (p.arg.vec_len == 0 || p.found_pages == p.arg.max_pages)
+ break;
+ }
+
+ /* ENOSPC signifies early stop (buffer full) from the walk. */
+ if (!ret || ret == -ENOSPC)
+ ret = n_ranges_out;
+
+ /* The walk_end isn't set when ret is zero */
+ if (!p.arg.walk_end)
+ p.arg.walk_end = p.arg.end;
+ if (pagemap_scan_writeback_args(&p.arg, uarg))
+ ret = -EFAULT;
+
+ kfree(p.vec_buf);
+ return ret;
+}
+
+static long do_pagemap_cmd(struct file *file, unsigned int cmd,
+ unsigned long arg)
+{
+ struct mm_struct *mm = file->private_data;
+
+ switch (cmd) {
+ case PAGEMAP_SCAN:
+ return do_pagemap_scan(mm, arg);
+
+ default:
+ return -EINVAL;
+ }
+}
+
const struct file_operations proc_pagemap_operations = {
.llseek = mem_lseek, /* borrow this */
.read = pagemap_read,
.open = pagemap_open,
.release = pagemap_release,
+ .unlocked_ioctl = do_pagemap_cmd,
+ .compat_ioctl = do_pagemap_cmd,
};
#endif /* CONFIG_PROC_PAGE_MONITOR */
@@ -1945,8 +2686,9 @@ static int show_numa_map(struct seq_file *m, void *v)
struct numa_maps *md = &numa_priv->md;
struct file *file = vma->vm_file;
struct mm_struct *mm = vma->vm_mm;
- struct mempolicy *pol;
char buffer[64];
+ struct mempolicy *pol;
+ pgoff_t ilx;
int nid;
if (!mm)
@@ -1955,7 +2697,7 @@ static int show_numa_map(struct seq_file *m, void *v)
/* Ensure we start with an empty set of numa_maps statistics. */
memset(md, 0, sizeof(*md));
- pol = __get_vma_policy(vma, vma->vm_start);
+ pol = __get_vma_policy(vma, vma->vm_start, &ilx);
if (pol) {
mpol_to_str(buffer, sizeof(buffer), pol);
mpol_cond_put(pol);
@@ -1967,7 +2709,7 @@ static int show_numa_map(struct seq_file *m, void *v)
if (file) {
seq_puts(m, " file=");
- seq_file_path(m, file, "\n\t= ");
+ seq_path(m, file_user_path(file), "\n\t= ");
} else if (vma_is_initial_heap(vma)) {
seq_puts(m, " heap");
} else if (vma_is_initial_stack(vma)) {
diff --git a/fs/proc/task_nommu.c b/fs/proc/task_nommu.c
index 7cebd397cc..bce6745330 100644
--- a/fs/proc/task_nommu.c
+++ b/fs/proc/task_nommu.c
@@ -157,7 +157,7 @@ static int nommu_vma_show(struct seq_file *m, struct vm_area_struct *vma)
if (file) {
seq_pad(m, ' ');
- seq_file_path(m, file, "");
+ seq_path(m, file_user_path(file), "");
} else if (mm && vma_is_initial_stack(vma)) {
seq_pad(m, ' ');
seq_puts(m, "[stack]");
diff --git a/fs/proc/thread_self.c b/fs/proc/thread_self.c
index 63ac1f9328..0e5050d6ab 100644
--- a/fs/proc/thread_self.c
+++ b/fs/proc/thread_self.c
@@ -46,7 +46,7 @@ int proc_setup_thread_self(struct super_block *s)
struct inode *inode = new_inode(s);
if (inode) {
inode->i_ino = thread_self_inum;
- inode->i_mtime = inode->i_atime = inode_set_ctime_current(inode);
+ simple_inode_init_ts(inode);
inode->i_mode = S_IFLNK | S_IRWXUGO;
inode->i_uid = GLOBAL_ROOT_UID;
inode->i_gid = GLOBAL_ROOT_GID;