From: Yu Kuai Date: Mon, 23 Feb 2026 02:40:35 +0000 (+0800) Subject: md/md-llbitmap: raise barrier before state machine transition X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=ef4ca3d4bf09716cff9ba00eb0351deadc8417ab;p=thirdparty%2Fkernel%2Flinux.git md/md-llbitmap: raise barrier before state machine transition Move the barrier raise operation before calling llbitmap_state_machine() in both llbitmap_start_write() and llbitmap_start_discard(). This ensures the barrier is in place before any state transitions occur, preventing potential race conditions where the state machine could complete before the barrier is properly raised. Cc: stable@vger.kernel.org Fixes: 5ab829f1971d ("md/md-llbitmap: introduce new lockless bitmap") Link: https://lore.kernel.org/linux-raid/20260223024038.3084853-3-yukuai@fnnas.com Signed-off-by: Yu Kuai --- diff --git a/drivers/md/md-llbitmap.c b/drivers/md/md-llbitmap.c index 6b2d27de1528..cdfecaca216b 100644 --- a/drivers/md/md-llbitmap.c +++ b/drivers/md/md-llbitmap.c @@ -1070,12 +1070,12 @@ static void llbitmap_start_write(struct mddev *mddev, sector_t offset, int page_start = (start + BITMAP_DATA_OFFSET) >> PAGE_SHIFT; int page_end = (end + BITMAP_DATA_OFFSET) >> PAGE_SHIFT; - llbitmap_state_machine(llbitmap, start, end, BitmapActionStartwrite); - while (page_start <= page_end) { llbitmap_raise_barrier(llbitmap, page_start); page_start++; } + + llbitmap_state_machine(llbitmap, start, end, BitmapActionStartwrite); } static void llbitmap_end_write(struct mddev *mddev, sector_t offset, @@ -1102,12 +1102,12 @@ static void llbitmap_start_discard(struct mddev *mddev, sector_t offset, int page_start = (start + BITMAP_DATA_OFFSET) >> PAGE_SHIFT; int page_end = (end + BITMAP_DATA_OFFSET) >> PAGE_SHIFT; - llbitmap_state_machine(llbitmap, start, end, BitmapActionDiscard); - while (page_start <= page_end) { llbitmap_raise_barrier(llbitmap, page_start); page_start++; } + + llbitmap_state_machine(llbitmap, start, end, BitmapActionDiscard); } static void llbitmap_end_discard(struct mddev *mddev, sector_t offset,