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-rw-r--r--mm/filemap.c2
-rw-r--r--mm/frame_vector.c31
-rw-r--r--mm/hugetlb.c2
-rw-r--r--mm/memcontrol.c15
-rw-r--r--mm/migrate.c5
-rw-r--r--mm/page_alloc.c65
6 files changed, 79 insertions, 41 deletions
diff --git a/mm/filemap.c b/mm/filemap.c
index f2e777003..e61ec2c88 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -3140,7 +3140,7 @@ ssize_t generic_perform_write(struct file *file,
unsigned long offset; /* Offset into pagecache page */
unsigned long bytes; /* Bytes to write to page */
size_t copied; /* Bytes copied from user */
- void *fsdata;
+ void *fsdata = NULL;
offset = (pos & (PAGE_SIZE - 1));
bytes = min_t(unsigned long, PAGE_SIZE - offset,
diff --git a/mm/frame_vector.c b/mm/frame_vector.c
index c64dca6e2..7124410a0 100644
--- a/mm/frame_vector.c
+++ b/mm/frame_vector.c
@@ -37,7 +37,6 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
struct mm_struct *mm = current->mm;
struct vm_area_struct *vma;
int ret = 0;
- int err;
int locked;
if (nr_frames == 0)
@@ -72,32 +71,14 @@ int get_vaddr_frames(unsigned long start, unsigned int nr_frames,
vec->is_pfns = false;
ret = get_user_pages_locked(start, nr_frames,
gup_flags, (struct page **)(vec->ptrs), &locked);
- goto out;
+ if (likely(ret > 0))
+ goto out;
}
- vec->got_ref = false;
- vec->is_pfns = true;
- do {
- unsigned long *nums = frame_vector_pfns(vec);
-
- while (ret < nr_frames && start + PAGE_SIZE <= vma->vm_end) {
- err = follow_pfn(vma, start, &nums[ret]);
- if (err) {
- if (ret == 0)
- ret = err;
- goto out;
- }
- start += PAGE_SIZE;
- ret++;
- }
- /*
- * We stop if we have enough pages or if VMA doesn't completely
- * cover the tail page.
- */
- if (ret >= nr_frames || start < vma->vm_end)
- break;
- vma = find_vma_intersection(mm, start, start + 1);
- } while (vma && vma->vm_flags & (VM_IO | VM_PFNMAP));
+ /* This used to (racily) return non-refcounted pfns. Let people know */
+ WARN_ONCE(1, "get_vaddr_frames() cannot follow VM_IO mapping");
+ vec->nr_frames = 0;
+
out:
if (locked)
up_read(&mm->mmap_sem);
diff --git a/mm/hugetlb.c b/mm/hugetlb.c
index 45e874faf..47e98a572 100644
--- a/mm/hugetlb.c
+++ b/mm/hugetlb.c
@@ -2116,11 +2116,11 @@ struct page *alloc_huge_page(struct vm_area_struct *vma,
page = alloc_buddy_huge_page_with_mpol(h, vma, addr);
if (!page)
goto out_uncharge_cgroup;
+ spin_lock(&hugetlb_lock);
if (!avoid_reserve && vma_has_reserves(vma, gbl_chg)) {
SetPagePrivate(page);
h->resv_huge_pages--;
}
- spin_lock(&hugetlb_lock);
list_move(&page->lru, &h->hugepage_activelist);
/* Fall through */
}
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index f3aa6e621..bc4c61dcf 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -4120,6 +4120,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
unsigned int efd, cfd;
struct fd efile;
struct fd cfile;
+ struct dentry *cdentry;
const char *name;
char *endp;
int ret;
@@ -4171,6 +4172,16 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
goto out_put_cfile;
/*
+ * The control file must be a regular cgroup1 file. As a regular cgroup
+ * file can't be renamed, it's safe to access its name afterwards.
+ */
+ cdentry = cfile.file->f_path.dentry;
+ if (cdentry->d_sb->s_type != &cgroup_fs_type || !d_is_reg(cdentry)) {
+ ret = -EINVAL;
+ goto out_put_cfile;
+ }
+
+ /*
* Determine the event callbacks and set them in @event. This used
* to be done via struct cftype but cgroup core no longer knows
* about these events. The following is crude but the whole thing
@@ -4178,7 +4189,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
*
* DO NOT ADD NEW FILES.
*/
- name = cfile.file->f_path.dentry->d_name.name;
+ name = cdentry->d_name.name;
if (!strcmp(name, "memory.usage_in_bytes")) {
event->register_event = mem_cgroup_usage_register_event;
@@ -4202,7 +4213,7 @@ static ssize_t memcg_write_event_control(struct kernfs_open_file *of,
* automatically removed on cgroup destruction but the removal is
* asynchronous, so take an extra ref on @css.
*/
- cfile_css = css_tryget_online_from_dir(cfile.file->f_path.dentry->d_parent,
+ cfile_css = css_tryget_online_from_dir(cdentry->d_parent,
&memory_cgrp_subsys);
ret = -EINVAL;
if (IS_ERR(cfile_css))
diff --git a/mm/migrate.c b/mm/migrate.c
index 76f8dedc0..171573613 100644
--- a/mm/migrate.c
+++ b/mm/migrate.c
@@ -2359,13 +2359,14 @@ next:
migrate->dst[migrate->npages] = 0;
migrate->src[migrate->npages++] = mpfn;
}
- arch_leave_lazy_mmu_mode();
- pte_unmap_unlock(ptep - 1, ptl);
/* Only flush the TLB if we actually modified any entries */
if (unmapped)
flush_tlb_range(walk->vma, start, end);
+ arch_leave_lazy_mmu_mode();
+ pte_unmap_unlock(ptep - 1, ptl);
+
return 0;
}
diff --git a/mm/page_alloc.c b/mm/page_alloc.c
index 9c35403d9..1cffd4e1f 100644
--- a/mm/page_alloc.c
+++ b/mm/page_alloc.c
@@ -3779,6 +3779,30 @@ void fs_reclaim_release(gfp_t gfp_mask)
EXPORT_SYMBOL_GPL(fs_reclaim_release);
#endif
+/*
+ * Zonelists may change due to hotplug during allocation. Detect when zonelists
+ * have been rebuilt so allocation retries. Reader side does not lock and
+ * retries the allocation if zonelist changes. Writer side is protected by the
+ * embedded spin_lock.
+ */
+static DEFINE_SEQLOCK(zonelist_update_seq);
+
+static unsigned int zonelist_iter_begin(void)
+{
+ if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE))
+ return read_seqbegin(&zonelist_update_seq);
+
+ return 0;
+}
+
+static unsigned int check_retry_zonelist(unsigned int seq)
+{
+ if (IS_ENABLED(CONFIG_MEMORY_HOTREMOVE))
+ return read_seqretry(&zonelist_update_seq, seq);
+
+ return seq;
+}
+
/* Perform direct synchronous page reclaim */
static int
__perform_reclaim(gfp_t gfp_mask, unsigned int order,
@@ -4084,6 +4108,7 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
int compaction_retries;
int no_progress_loops;
unsigned int cpuset_mems_cookie;
+ unsigned int zonelist_iter_cookie;
int reserve_flags;
/*
@@ -4094,11 +4119,12 @@ __alloc_pages_slowpath(gfp_t gfp_mask, unsigned int order,
(__GFP_ATOMIC|__GFP_DIRECT_RECLAIM)))
gfp_mask &= ~__GFP_ATOMIC;
-retry_cpuset:
+restart:
compaction_retries = 0;
no_progress_loops = 0;
compact_priority = DEF_COMPACT_PRIORITY;
cpuset_mems_cookie = read_mems_allowed_begin();
+ zonelist_iter_cookie = zonelist_iter_begin();
/*
* The fast path uses conservative alloc_flags to succeed only until
@@ -4247,9 +4273,13 @@ retry:
goto retry;
- /* Deal with possible cpuset update races before we start OOM killing */
- if (check_retry_cpuset(cpuset_mems_cookie, ac))
- goto retry_cpuset;
+ /*
+ * Deal with possible cpuset update races or zonelist updates to avoid
+ * a unnecessary OOM kill.
+ */
+ if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
+ check_retry_zonelist(zonelist_iter_cookie))
+ goto restart;
/* Reclaim has failed us, start killing things */
page = __alloc_pages_may_oom(gfp_mask, order, ac, &did_some_progress);
@@ -4269,9 +4299,13 @@ retry:
}
nopage:
- /* Deal with possible cpuset update races before we fail */
- if (check_retry_cpuset(cpuset_mems_cookie, ac))
- goto retry_cpuset;
+ /*
+ * Deal with possible cpuset update races or zonelist updates to avoid
+ * a unnecessary OOM kill.
+ */
+ if (check_retry_cpuset(cpuset_mems_cookie, ac) ||
+ check_retry_zonelist(zonelist_iter_cookie))
+ goto restart;
/*
* Make sure that __GFP_NOFAIL request doesn't leak out and make sure
@@ -4569,6 +4603,18 @@ refill:
/* reset page count bias and offset to start of new frag */
nc->pagecnt_bias = PAGE_FRAG_CACHE_MAX_SIZE + 1;
offset = size - fragsz;
+ if (unlikely(offset < 0)) {
+ /*
+ * The caller is trying to allocate a fragment
+ * with fragsz > PAGE_SIZE but the cache isn't big
+ * enough to satisfy the request, this may
+ * happen in low memory conditions.
+ * We don't release the cache page because
+ * it could make memory pressure worse
+ * so we simply return NULL here.
+ */
+ return NULL;
+ }
}
nc->pagecnt_bias--;
@@ -5379,9 +5425,8 @@ static void __build_all_zonelists(void *data)
int nid;
int __maybe_unused cpu;
pg_data_t *self = data;
- static DEFINE_SPINLOCK(lock);
- spin_lock(&lock);
+ write_seqlock(&zonelist_update_seq);
#ifdef CONFIG_NUMA
memset(node_load, 0, sizeof(node_load));
@@ -5414,7 +5459,7 @@ static void __build_all_zonelists(void *data)
#endif
}
- spin_unlock(&lock);
+ write_sequnlock(&zonelist_update_seq);
}
static noinline void __init
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 16:21:41 +0000