Commit 377a7b0b authored by Mike Christie's avatar Mike Christie Committed by Martin K. Petersen
Browse files

scsi: virtio_scsi: Drop DID_NEXUS_FAILURE use 

DID_NEXUS_FAILURE is internal to the SCSI layer. Drivers must not use it
because:

 1. It's not propagated upwards, so SG IO/passthrough users will not see an
    error and think a command was successful.

 2. There is no handling for it in scsi_decide_disposition() so it results
    in entering SCSI error handling.

virtio_scsi gets this when something like qemu returns
VIRTIO_SCSI_S_NEXUS_FAILURE. It looks like qemu returns that error code if
host OS returns DID_NEXUS_FAILURE (qemu's internal
SCSI_HOST_RESERVATION_ERROR maps to DID_NEXUS_FAILURE). This shouldn't
happen for Linux since we don't propagate that error code to userspace.

This has us convert VIRTIO_SCSI_S_NEXUS_FAILURE to a
SAM_STAT_RESERVATION_CONFLICT in case some other virt layer is returning
it. In that case we will still get the reservation confict failure we
expect.

Link: https://lore.kernel.org/r/20220812010027.8251-6-michael.christie@oracle.com


Acked-by: default avatarPaolo Bonzini <pbonzini@redhat.com>
Acked-by: default avatarMichael S. Tsirkin <mst@redhat.com>
Signed-off-by: default avatarMike Christie <michael.christie@oracle.com>
Signed-off-by: default avatarMartin K. Petersen <martin.petersen@oracle.com>
parent beb4dac8

drivers/scsi/virtio_scsi.c

+1 −1
Original line number Diff line number Diff line
@@ -144,7 +144,7 @@ static void virtscsi_complete_cmd(struct virtio_scsi *vscsi, void *buf) 
		set_host_byte(sc, DID_BAD_TARGET);

		break;

	case VIRTIO_SCSI_S_NEXUS_FAILURE:

		set_host_byte(sc, DID_NEXUS_FAILURE);

		set_status_byte(sc, SAM_STAT_RESERVATION_CONFLICT);

		break;

	default:

		scmd_printk(KERN_WARNING, sc, "Unknown response %d",