[PATCH 3.16 006/136] scsi: sd: Ignore a failure to sync cache due to lack of authorization

Ben Hutchings
2019-12-17T00:56:30Z

From: Oliver Neukum <oneukum@suse.com>

commit 21e3d6c81179bbdfa279efc8de456c34b814cfd2 upstream.

I've got a report about a UAS drive enclosure reporting back Sense: Logical
unit access not authorized if the drive it holds is password protected.
While the drive is obviously unusable in that state as a mass storage
device, it still exists as a sd device and when the system is asked to
perform a suspend of the drive, it will be sent a SYNCHRONIZE CACHE. If
that fails due to password protection, the error must be ignored.

Link: https://lore.kernel.org/r/20190903101840.16483-1-oneukum@suse.com
Signed-off-by: Oliver Neukum <oneukum@suse.com>
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>
[bwh: Backported to 3.16: sshdr is a struct not a pointer here]
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
---
drivers/scsi/sd.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/scsi/sd.c
+++ b/drivers/scsi/sd.c
@@ -1470,7 +1470,8 @@ static int sd_sync_cache(struct scsi_dis
/* we need to evaluate the error return */
if (scsi_sense_valid(&sshdr) &&
(sshdr.asc == 0x3a || /* medium not present */
- sshdr.asc == 0x20)) /* invalid command */
+ sshdr.asc == 0x20 || /* invalid command */
+ (sshdr.asc == 0x74 && sshdr.ascq == 0x71))) /* drive is password locked */
/* this is no error here */
return 0;