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author | Kirill A. Shutemov <kirill.shutemov@linux.intel.com> | 2016-05-27 14:27:38 -0700 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2016-05-27 14:49:37 -0700 |
commit | 0798d3c022dc63eb0ec02b511e1f76ca8411ef8e (patch) | |
tree | 64fd1d7fe4f727f319d34904a5a587f07a95d18e /mm | |
parent | e2fe14564d3316d1625ed20bf1083995f4960893 (diff) | |
download | lwn-0798d3c022dc63eb0ec02b511e1f76ca8411ef8e.tar.gz lwn-0798d3c022dc63eb0ec02b511e1f76ca8411ef8e.zip |
mm: thp: avoid false positive VM_BUG_ON_PAGE in page_move_anon_rmap()
If page_move_anon_rmap() is refiling a pmd-splitted THP mapped in a tail
page from a pte, the "address" must be THP aligned in order for the
page->index bugcheck to pass in the CONFIG_DEBUG_VM=y builds.
Link: http://lkml.kernel.org/r/1464253620-106404-1-git-send-email-kirill.shutemov@linux.intel.com
Fixes: 6d0a07edd17c ("mm: thp: calculate the mapcount correctly for THP pages during WP faults")
Signed-off-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reported-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Tested-by: Mika Westerberg <mika.westerberg@linux.intel.com>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: <stable@vger.kernel.org> [4.5]
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
-rw-r--r-- | mm/rmap.c | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/mm/rmap.c b/mm/rmap.c index 8a839935b18c..0ea5d9071b32 100644 --- a/mm/rmap.c +++ b/mm/rmap.c @@ -1098,6 +1098,8 @@ void page_move_anon_rmap(struct page *page, VM_BUG_ON_PAGE(!PageLocked(page), page); VM_BUG_ON_VMA(!anon_vma, vma); + if (IS_ENABLED(CONFIG_DEBUG_VM) && PageTransHuge(page)) + address &= HPAGE_PMD_MASK; VM_BUG_ON_PAGE(page->index != linear_page_index(vma, address), page); anon_vma = (void *) anon_vma + PAGE_MAPPING_ANON; |