4.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johannes Thumshirn <jthumshirn@xxxxxxx> [ Upstream commit f1f1fadacaf08b7cf11714c0c29f8fa4d4ef68a9 ] When sd_init_command() get's a command with a unknown req_op() it crashes the system via BUG(). This makes debugging the actual reason for the broken request cmd_flags pretty hard as the system is down before it's able to write out debugging data on the serial console or the trace buffer. Change the BUG() to a WARN_ON() and return BLKPREP_KILL to fail gracefully and return an I/O error to the producer of the request. Signed-off-by: Johannes Thumshirn <jthumshirn@xxxxxxx> Cc: Hannes Reinecke <hare@xxxxxxx> Cc: Bart Van Assche <bvanassche@xxxxxxx> Cc: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Christoph Hellwig <hch@xxxxxx> Reviewed-by: Bart Van Assche <bvanassche@xxxxxxx> Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx> Signed-off-by: Sasha Levin <alexander.levin@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- drivers/scsi/sd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1277,7 +1277,8 @@ static int sd_init_command(struct scsi_c case REQ_OP_ZONE_RESET: return sd_zbc_setup_reset_cmnd(cmd); default: - BUG(); + WARN_ON_ONCE(1); + return BLKPREP_KILL; } }