This is a note to let you know that I've just added the patch titled ata: sata_mv, avoid trigerrable BUG_ON to the 5.4-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: ata-sata_mv-avoid-trigerrable-bug_on.patch and it can be found in the queue-5.4 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit c58f78654648ca3c4df01bf7c5993556b14e4201 Author: Jiri Slaby <jslaby@xxxxxxx> Date: Thu Oct 31 10:59:46 2019 +0100 ata: sata_mv, avoid trigerrable BUG_ON [ Upstream commit e9f691d899188679746eeb96e6cb520459eda9b4 ] There are several reports that the BUG_ON on unsupported command in mv_qc_prep can be triggered under some circumstances: https://bugzilla.suse.com/show_bug.cgi?id=1110252 https://serverfault.com/questions/888897/raid-problems-after-power-outage https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1652185 https://bugs.centos.org/view.php?id=14998 Let sata_mv handle the failure gracefully: warn about that incl. the failed command number and return an AC_ERR_INVALID error. We can do that now thanks to the previous patch. Remove also the long-standing FIXME. [v2] use %.2x as commands are defined as hexa. Signed-off-by: Jiri Slaby <jslaby@xxxxxxx> Cc: Jens Axboe <axboe@xxxxxxxxx> Cc: linux-ide@xxxxxxxxxxxxxxx Cc: Sergei Shtylyov <sergei.shtylyov@xxxxxxxxxxxxxxxxxx> Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/ata/sata_mv.c b/drivers/ata/sata_mv.c index bde695a320973..0229b618d0eee 100644 --- a/drivers/ata/sata_mv.c +++ b/drivers/ata/sata_mv.c @@ -2098,12 +2098,10 @@ static void mv_qc_prep(struct ata_queued_cmd *qc) * non-NCQ mode are: [RW] STREAM DMA and W DMA FUA EXT, none * of which are defined/used by Linux. If we get here, this * driver needs work. - * - * FIXME: modify libata to give qc_prep a return value and - * return error here. */ - BUG_ON(tf->command); - break; + ata_port_err(ap, "%s: unsupported command: %.2x\n", __func__, + tf->command); + return AC_ERR_INVALID; } mv_crqb_pack_cmd(cw++, tf->nsect, ATA_REG_NSECT, 0); mv_crqb_pack_cmd(cw++, tf->hob_lbal, ATA_REG_LBAL, 0);