4.9-stable review patch. If anyone has any objections, please let me know.
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From: Johannes Thumshirn jthumshirn@suse.de
[ 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@suse.de Cc: Hannes Reinecke hare@suse.de Cc: Bart Van Assche bvanassche@acm.org Cc: Christoph Hellwig hch@lst.de Reviewed-by: Christoph Hellwig hch@lst.de Reviewed-by: Bart Van Assche bvanassche@acm.org Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Sasha Levin alexander.levin@microsoft.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/scsi/sd.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/scsi/sd.c +++ b/drivers/scsi/sd.c @@ -1158,7 +1158,8 @@ static int sd_init_command(struct scsi_c case REQ_OP_WRITE: return sd_setup_read_write_cmnd(cmd); default: - BUG(); + WARN_ON_ONCE(1); + return BLKPREP_KILL; } }