From mboxrd@z Thu Jan 1 00:00:00 1970 From: Mikulas Patocka Subject: [PATCH] dm-raid: stack limits instead of overwriting them. Date: Thu, 24 Sep 2020 12:26:18 -0400 (EDT) Message-ID: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: dm-devel-bounces@redhat.com Errors-To: dm-devel-bounces@redhat.com To: Mike Snitzer , Zdenek Kabelac Cc: dm-devel@redhat.com List-Id: dm-devel.ids This patch fixes a warning WARN_ON_ONCE(!q->limits.discard_granularity). The reason is that the function raid_io_hints overwrote limits->discard_granularity with zero. We need to properly stack the limits instead of overwriting them. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org --- drivers/md/dm-raid.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) Index: linux-2.6/drivers/md/dm-raid.c =================================================================== --- linux-2.6.orig/drivers/md/dm-raid.c 2020-09-24 18:16:45.000000000 +0200 +++ linux-2.6/drivers/md/dm-raid.c 2020-09-24 18:16:45.000000000 +0200 @@ -3734,8 +3734,8 @@ static void raid_io_hints(struct dm_targ * RAID0/4/5/6 don't and process large discard bios properly. */ if (rs_is_raid1(rs) || rs_is_raid10(rs)) { - limits->discard_granularity = chunk_size_bytes; - limits->max_discard_sectors = rs->md.chunk_sectors; + limits->discard_granularity = max(limits->discard_granularity, chunk_size_bytes); + limits->max_discard_sectors = min_not_zero(limits->max_discard_sectors, (unsigned)rs->md.chunk_sectors); } }