The speculative page fault handler which is run without holding the mmap_sem is calling lru_cache_add_active_or_unevictable() but the vm_flags is not guaranteed to remain constant. Introducing __lru_cache_add_active_or_unevictable() which has the vma flags value parameter instead of the vma pointer.
Acked-by: David Rientjes <rient...@google.com> Signed-off-by: Laurent Dufour <lduf...@linux.vnet.ibm.com> --- include/linux/swap.h | 10 ++++++++-- mm/memory.c | 8 ++++---- mm/swap.c | 6 +++--- 3 files changed, 15 insertions(+), 9 deletions(-) diff --git a/include/linux/swap.h b/include/linux/swap.h index f73eafcaf4e9..730c14738574 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -338,8 +338,14 @@ extern void deactivate_file_page(struct page *page); extern void mark_page_lazyfree(struct page *page); extern void swap_setup(void); -extern void lru_cache_add_active_or_unevictable(struct page *page, - struct vm_area_struct *vma); +extern void __lru_cache_add_active_or_unevictable(struct page *page, + unsigned long vma_flags); + +static inline void lru_cache_add_active_or_unevictable(struct page *page, + struct vm_area_struct *vma) +{ + return __lru_cache_add_active_or_unevictable(page, vma->vm_flags); +} /* linux/mm/vmscan.c */ extern unsigned long zone_reclaimable_pages(struct zone *zone); diff --git a/mm/memory.c b/mm/memory.c index cb6310b74cfb..deac7f12d777 100644 --- a/mm/memory.c +++ b/mm/memory.c @@ -2569,7 +2569,7 @@ static int wp_page_copy(struct vm_fault *vmf) ptep_clear_flush_notify(vma, vmf->address, vmf->pte); page_add_new_anon_rmap(new_page, vma, vmf->address, false); mem_cgroup_commit_charge(new_page, memcg, false, false); - lru_cache_add_active_or_unevictable(new_page, vma); + __lru_cache_add_active_or_unevictable(new_page, vmf->vma_flags); /* * We call the notify macro here because, when using secondary * mmu page tables (such as kvm shadow page tables), we want the @@ -3105,7 +3105,7 @@ int do_swap_page(struct vm_fault *vmf) if (unlikely(page != swapcache && swapcache)) { page_add_new_anon_rmap(page, vma, vmf->address, false); mem_cgroup_commit_charge(page, memcg, false, false); - lru_cache_add_active_or_unevictable(page, vma); + __lru_cache_add_active_or_unevictable(page, vmf->vma_flags); } else { do_page_add_anon_rmap(page, vma, vmf->address, exclusive); mem_cgroup_commit_charge(page, memcg, true, false); @@ -3256,7 +3256,7 @@ static int do_anonymous_page(struct vm_fault *vmf) inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); page_add_new_anon_rmap(page, vma, vmf->address, false); mem_cgroup_commit_charge(page, memcg, false, false); - lru_cache_add_active_or_unevictable(page, vma); + __lru_cache_add_active_or_unevictable(page, vmf->vma_flags); setpte: set_pte_at(vma->vm_mm, vmf->address, vmf->pte, entry); @@ -3510,7 +3510,7 @@ int alloc_set_pte(struct vm_fault *vmf, struct mem_cgroup *memcg, inc_mm_counter_fast(vma->vm_mm, MM_ANONPAGES); page_add_new_anon_rmap(page, vma, vmf->address, false); mem_cgroup_commit_charge(page, memcg, false, false); - lru_cache_add_active_or_unevictable(page, vma); + __lru_cache_add_active_or_unevictable(page, vmf->vma_flags); } else { inc_mm_counter_fast(vma->vm_mm, mm_counter_file(page)); page_add_file_rmap(page, false); diff --git a/mm/swap.c b/mm/swap.c index 26fc9b5f1b6c..ba97d437e68a 100644 --- a/mm/swap.c +++ b/mm/swap.c @@ -456,12 +456,12 @@ void lru_cache_add(struct page *page) * directly back onto it's zone's unevictable list, it does NOT use a * per cpu pagevec. */ -void lru_cache_add_active_or_unevictable(struct page *page, - struct vm_area_struct *vma) +void __lru_cache_add_active_or_unevictable(struct page *page, + unsigned long vma_flags) { VM_BUG_ON_PAGE(PageLRU(page), page); - if (likely((vma->vm_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) + if (likely((vma_flags & (VM_LOCKED | VM_SPECIAL)) != VM_LOCKED)) SetPageActive(page); else if (!TestSetPageMlocked(page)) { /* -- 2.7.4