These commands # modprobe brd rd_size=1048576 # vgcreate vg /dev/ram* # lvcreate -m4 -L10 -n lv vg trigger the following warnings: device-mapper: table: 252:10: adding target device (start sect 0 len 24576) caused an alignment inconsistency device-mapper: table: 252:10: adding target device (start sect 0 len 24576) caused an alignment inconsistency The warnings are caused by the fact that io_min is 512 and physical block size is 4096. If there's chunk-less raid, such as raid1, io_min shouldn't be set to zero because it would be raised to 512 and it would trigger the warning. Signed-off-by: Mikulas Patocka Cc: stable@vger.kernel.org --- drivers/md/dm-raid.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) Index: linux-2.6/drivers/md/dm-raid.c =================================================================== --- linux-2.6.orig/drivers/md/dm-raid.c 2025-09-15 15:56:34.000000000 +0200 +++ linux-2.6/drivers/md/dm-raid.c 2025-09-15 15:56:56.000000000 +0200 @@ -3813,8 +3813,10 @@ static void raid_io_hints(struct dm_targ struct raid_set *rs = ti->private; unsigned int chunk_size_bytes = to_bytes(rs->md.chunk_sectors); - limits->io_min = chunk_size_bytes; - limits->io_opt = chunk_size_bytes * mddev_data_stripes(rs); + if (chunk_size_bytes) { + limits->io_min = chunk_size_bytes; + limits->io_opt = chunk_size_bytes * mddev_data_stripes(rs); + } } static void raid_presuspend(struct dm_target *ti)