diff mbox series

[01/18] mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page

Message ID 20210205023203.MmSvWEbBn%akpm@linux-foundation.org
State New
Headers show
Series [01/18] mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page | expand

Commit Message

Andrew Morton Feb. 5, 2021, 2:32 a.m. UTC 
From: Muchun Song <songmuchun@bytedance.com>
Subject: mm: hugetlbfs: fix cannot migrate the fallocated HugeTLB page

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>
---

 fs/hugetlbfs/inode.c    |    3 ++-
 include/linux/hugetlb.h |    2 ++
 mm/hugetlb.c            |    2 +-
 3 files changed, 5 insertions(+), 2 deletions(-)
diff mbox series

Patch

--- a/fs/hugetlbfs/inode.c~mm-hugetlbfs-fix-cannot-migrate-the-fallocated-hugetlb-page
+++ a/fs/hugetlbfs/inode.c
@@ -735,9 +735,10 @@  static long hugetlbfs_fallocate(struct f
 
 		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);
--- a/include/linux/hugetlb.h~mm-hugetlbfs-fix-cannot-migrate-the-fallocated-hugetlb-page
+++ a/include/linux/hugetlb.h
@@ -770,6 +770,8 @@  static inline void huge_ptep_modify_prot
 }
 #endif
 
+void set_page_huge_active(struct page *page);
+
 #else	/* CONFIG_HUGETLB_PAGE */
 struct hstate {};
 
--- a/mm/hugetlb.c~mm-hugetlbfs-fix-cannot-migrate-the-fallocated-hugetlb-page
+++ a/mm/hugetlb.c
@@ -1349,7 +1349,7 @@  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]);