From: Miklos Szeredi Date: Wed, 28 Aug 2024 13:55:17 +0000 (+0200) Subject: fuse: clear PG_uptodate when using a stolen page X-Git-Tag: v6.11-rc7~42^2~2 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=76a51ac00ca2a72fe3e168b7fb0e70f75ba6f512;p=thirdparty%2Fkernel%2Flinux.git fuse: clear PG_uptodate when using a stolen page Originally when a stolen page was inserted into fuse's page cache by fuse_try_move_page(), it would be marked uptodate. Then fuse_readpages_end() would call SetPageUptodate() again on the already uptodate page. Commit 413e8f014c8b ("fuse: Convert fuse_readpages_end() to use folio_end_read()") changed that by replacing the SetPageUptodate() + unlock_page() combination with folio_end_read(), which does mostly the same, except it sets the uptodate flag with an xor operation, which in the above scenario resulted in the uptodate flag being cleared, which in turn resulted in EIO being returned on the read. Fix by clearing PG_uptodate instead of setting it in fuse_try_move_page(), conforming to the expectation of folio_end_read(). Reported-by: Jürg Billeter Debugged-by: Matthew Wilcox Fixes: 413e8f014c8b ("fuse: Convert fuse_readpages_end() to use folio_end_read()") Cc: # v6.10 Signed-off-by: Miklos Szeredi --- diff --git a/fs/fuse/dev.c b/fs/fuse/dev.c index a11461ef6022c..67443ef07285e 100644 --- a/fs/fuse/dev.c +++ b/fs/fuse/dev.c @@ -775,7 +775,6 @@ static int fuse_check_folio(struct folio *folio) (folio->flags & PAGE_FLAGS_CHECK_AT_PREP & ~(1 << PG_locked | 1 << PG_referenced | - 1 << PG_uptodate | 1 << PG_lru | 1 << PG_active | 1 << PG_workingset | @@ -820,9 +819,7 @@ static int fuse_try_move_page(struct fuse_copy_state *cs, struct page **pagep) newfolio = page_folio(buf->page); - if (!folio_test_uptodate(newfolio)) - folio_mark_uptodate(newfolio); - + folio_clear_uptodate(newfolio); folio_clear_mappedtodisk(newfolio); if (fuse_check_folio(newfolio) != 0)