The patch titled Subject: writeback: fix done_index when hitting the wbc->nr_to_write has been added to the -mm mm-unstable branch. Its filename is writeback-fix-done_index-when-hitting-the-wbc-nr_to_write.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/writeback-fix-done_index-when-hitting-the-wbc-nr_to_write.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Christoph Hellwig <hch@xxxxxx> Subject: writeback: fix done_index when hitting the wbc->nr_to_write Date: Thu, 15 Feb 2024 07:36:38 +0100 When write_cache_pages finishes writing out a folio, it fails to update done_index to account for the number of pages in the folio just written. That means when range_cyclic writeback is restarted, it will be restarted at this folio instead of after it as it should. Fix that by updating done_index before breaking out of the loop. Link: https://lkml.kernel.org/r/20240215063649.2164017-4-hch@xxxxxx Signed-off-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Brian Foster <bfoster@xxxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> Acked-by: Dave Chinner <dchinner@xxxxxxxxxx> Cc: Christian Brauner <brauner@xxxxxxxxxx> Cc: David Howells <dhowells@xxxxxxxxxx> Cc: "Matthew Wilcox (Oracle)" <willy@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/page-writeback.c | 1 + 1 file changed, 1 insertion(+) --- a/mm/page-writeback.c~writeback-fix-done_index-when-hitting-the-wbc-nr_to_write +++ a/mm/page-writeback.c @@ -2505,6 +2505,7 @@ continue_unlock: * keep going until we have written all the pages * we tagged for writeback prior to entering this loop. */ + done_index = folio->index + nr; wbc->nr_to_write -= nr; if (wbc->nr_to_write <= 0 && wbc->sync_mode == WB_SYNC_NONE) { _ Patches currently in -mm which might be from hch@xxxxxx are writeback-dont-call-mapping_set_error-on-aop_writepage_activate.patch writeback-fix-done_index-when-hitting-the-wbc-nr_to_write.patch writeback-also-update-wbc-nr_to_write-on-writeback-failure.patch writeback-only-update-writeback_index-for-range_cyclic-writeback.patch writeback-rework-the-loop-termination-condition-in-write_cache_pages.patch writeback-add-a-writeback-iterator.patch