From: Mike Snitzer <snitzer@xxxxxxxxxx> commit cc07d72bf350b77faeffee1c37bc52197171473f upstream. Block core warned that discard_granularity was 0 for dm-raid with personality of raid1. Reason is that raid_io_hints() was incorrectly special-casing raid1 rather than raid0. Fix raid_io_hints() by removing discard limits settings for raid1. Check for raid0 instead. Fixes: 61697a6abd24a ("dm: eliminate 'split_discard_bios' flag from DM target interface") Cc: stable@xxxxxxxxxxxxxxx Reported-by: Zdenek Kabelac <zkabelac@xxxxxxxxxx> Reported-by: Mikulas Patocka <mpatocka@xxxxxxxxxx> Reported-by: Stephan Bärwolf <stephan@xxxxxxxxxxxxxxx> Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/md/dm-raid.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/drivers/md/dm-raid.c +++ b/drivers/md/dm-raid.c @@ -3744,10 +3744,10 @@ static void raid_io_hints(struct dm_targ blk_limits_io_opt(limits, chunk_size_bytes * mddev_data_stripes(rs)); /* - * RAID1 and RAID10 personalities require bio splitting, - * RAID0/4/5/6 don't and process large discard bios properly. + * RAID0 and RAID10 personalities require bio splitting, + * RAID1/4/5/6 don't and process large discard bios properly. */ - if (rs_is_raid1(rs) || rs_is_raid10(rs)) { + if (rs_is_raid0(rs) || rs_is_raid10(rs)) { limits->discard_granularity = chunk_size_bytes; limits->max_discard_sectors = rs->md.chunk_sectors; }