[PATCH v10 3/7] filemap: update offset check in filemap_fault()

From: Song Liu
Date: Thu Aug 01 2019 - 14:43:24 EST


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);

Acked-by: Rik van Riel <riel@xxxxxxxxxxx>
Acked-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>
Acked-by: Johannes Weiner <hannes@xxxxxxxxxxx>
Signed-off-by: Song Liu <songliubraving@xxxxxx>
---
mm/filemap.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/mm/filemap.c b/mm/filemap.c
index aaee1ef96f6d..97c7b7b92c20 100644
--- a/mm/filemap.c
+++ b/mm/filemap.c
@@ -2542,7 +2542,7 @@ vm_fault_t filemap_fault(struct vm_fault *vmf)
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
--
2.17.1