From: Muchun Song songmuchun@bytedance.com
stable inclusion from linux-4.19.175 commit b6e04c19c5b2060c91b07acec5d650a1beb6855f
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commit 585fc0d2871c9318c949fbf45b1f081edd489e96 upstream.
If a new hugetlb page is allocated during fallocate it will not be marked as active (set_page_huge_active) which will result in a later isolate_huge_page failure when the page migration code would like to move that page. Such a failure would be unexpected and wrong.
Only export set_page_huge_active, just leave clear_page_huge_active as static. Because there are no external users.
Link: https://lkml.kernel.org/r/20210115124942.46403-3-songmuchun@bytedance.com Fixes: 70c3547e36f5 (hugetlbfs: add hugetlbfs_fallocate()) Signed-off-by: Muchun Song songmuchun@bytedance.com Acked-by: Michal Hocko mhocko@suse.com Reviewed-by: Mike Kravetz mike.kravetz@oracle.com Reviewed-by: Oscar Salvador osalvador@suse.de Cc: David Hildenbrand david@redhat.com Cc: Yang Shi shy828301@gmail.com Cc: stable@vger.kernel.org Signed-off-by: Andrew Morton akpm@linux-foundation.org Signed-off-by: Linus Torvalds torvalds@linux-foundation.org Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org Signed-off-by: Yang Yingliang yangyingliang@huawei.com Signed-off-by: Cheng Jian cj.chengjian@huawei.com --- fs/hugetlbfs/inode.c | 3 ++- include/linux/hugetlb.h | 3 +++ mm/hugetlb.c | 2 +- 3 files changed, 6 insertions(+), 2 deletions(-)
diff --git a/fs/hugetlbfs/inode.c b/fs/hugetlbfs/inode.c index a878f009347c..47a7b96cfe10 100644 --- a/fs/hugetlbfs/inode.c +++ b/fs/hugetlbfs/inode.c @@ -787,9 +787,10 @@ static int hugetlbfs_fallocate_chunk(pgoff_t start, pgoff_t end,
mutex_unlock(&hugetlb_fault_mutex_table[hash]);
+ set_page_huge_active(page); /* * unlock_page because locked by add_to_page_cache() - * page_put due to reference from alloc_huge_page() + * put_page() due to reference from alloc_huge_page() */ unlock_page(page); put_page(page); diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 3f355dfaf31f..8aec9d4220bd 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -549,6 +549,9 @@ static inline void set_huge_swap_pte_at(struct mm_struct *mm, unsigned long addr set_huge_pte_at(mm, addr, ptep, pte); } #endif + +void set_page_huge_active(struct page *page); + #else /* CONFIG_HUGETLB_PAGE */ struct hstate {}; #define alloc_huge_page(v, a, r) NULL diff --git a/mm/hugetlb.c b/mm/hugetlb.c index ea0902276cb5..5e029780a36c 100644 --- a/mm/hugetlb.c +++ b/mm/hugetlb.c @@ -1219,7 +1219,7 @@ bool page_huge_active(struct page *page) }
/* never called for tail page */ -static void set_page_huge_active(struct page *page) +void set_page_huge_active(struct page *page) { VM_BUG_ON_PAGE(!PageHeadHuge(page), page); SetPagePrivate(&page[1]);