filemap: update offset check in filemap_fault()

With THP, current check of offset:

    VM_BUG_ON_PAGE(page->index != offset, page);

is no longer accurate. Update it to:

    VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page);

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Song Liu <[email protected]>
Acked-by: Rik van Riel <[email protected]>
Acked-by: Kirill A. Shutemov <[email protected]>
Acked-by: Johannes Weiner <[email protected]>
Cc: Hillf Danton <[email protected]>
Cc: Hugh Dickins <[email protected]>
Cc: William Kucharski <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

diff --git a/mm/filemap.c b/mm/filemap.c
index 0b301103ea80e4c82dbc0aab9dc817b2d413b1ff..f4d2971abd7c6b188de4fd7c4592c75d1a795a1b 100644 (file)
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2545,7 +2545,7 @@ retry_find:
                put_page(page);
                goto retry_find;
        }
-       VM_BUG_ON_PAGE(page->index != offset, page);
+       VM_BUG_ON_PAGE(page_to_pgoff(page) != offset, page);
 
        /*
         * We have a locked page in the page cache, now we need to check