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@xxxxxxxxxxxxxxx> > > Signed-off-by: Jaegeuk Kim <jaegeuk@xxxxxxxxxx> > > --- > > 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); > > }
