On 03/26, Chao Yu wrote:
On 2023/3/24 5:39, Jaegeuk Kim wrote:
https://bugzilla.kernel.org/show_bug.cgi?id=216050
Somehow we're getting a page which has a different mapping. Let's avoid the infinite loop.
Cc: stable@vger.kernel.org Signed-off-by: Jaegeuk Kim jaegeuk@kernel.org
fs/f2fs/data.c | 8 ++------ 1 file changed, 2 insertions(+), 6 deletions(-)
diff --git a/fs/f2fs/data.c b/fs/f2fs/data.c index bf51e6e4eb64..80702c93e885 100644 --- a/fs/f2fs/data.c +++ b/fs/f2fs/data.c @@ -1329,18 +1329,14 @@ struct page *f2fs_get_lock_data_page(struct inode *inode, pgoff_t index, { struct address_space *mapping = inode->i_mapping; struct page *page; -repeat:
- page = f2fs_get_read_data_page(inode, index, 0, for_write, NULL); if (IS_ERR(page)) return page; /* wait for read completion */ lock_page(page);
- if (unlikely(page->mapping != mapping)) {
How about using such logic only for move_data_page() to limit affect for other paths?
Why move_data_page() only? If this happens, we'll fall into a loop in anywhere?
Jaegeuk, any thoughts about why mapping is mismatch in between page's one and inode->i_mapping?
After several times code review, I didn't get any clue about why f2fs always get the different mapping in a loop.
I couldn't find the path to happen this. So weird. Please check the history in the bug.
Maybe we can loop MM guys to check whether below folio_file_page() may return page which has different mapping?
Matthew may have some idea on this?
struct page *pagecache_get_page(struct address_space *mapping, pgoff_t index, int fgp_flags, gfp_t gfp) { struct folio *folio;
folio = __filemap_get_folio(mapping, index, fgp_flags, gfp); if (IS_ERR(folio)) return NULL; return folio_file_page(folio, index); }
Thanks,
f2fs_put_page(page, 1);goto repeat;- }
- if (unlikely(!PageUptodate(page))) {
- if (unlikely(page->mapping != mapping || !PageUptodate(page))) { f2fs_put_page(page, 1); return ERR_PTR(-EIO); }