3.16.70-rc1 review patch. If anyone has any objections, please let me know.
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From: Felipe Franciosi felipe@nutanix.com
commit 3722e6a52174d7c3a00e6f5efd006ca093f346c1 upstream.
The virtio scsi spec defines struct virtio_scsi_ctrl_tmf as a set of device-readable records and a single device-writable response entry:
struct virtio_scsi_ctrl_tmf { // Device-readable part le32 type; le32 subtype; u8 lun[8]; le64 id; // Device-writable part u8 response; }
The above should be organised as two descriptor entries (or potentially more if using VIRTIO_F_ANY_LAYOUT), but without any extra data after "le64 id" or after "u8 response".
The Linux driver doesn't respect that, with virtscsi_abort() and virtscsi_device_reset() setting cmd->sc before calling virtscsi_tmf(). It results in the original scsi command payload (or writable buffers) added to the tmf.
This fixes the problem by leaving cmd->sc zeroed out, which makes virtscsi_kick_cmd() add the tmf to the control vq without any payload.
Signed-off-by: Felipe Franciosi felipe@nutanix.com Reviewed-by: Paolo Bonzini pbonzini@redhat.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Ben Hutchings ben@decadent.org.uk --- drivers/scsi/virtio_scsi.c | 2 -- 1 file changed, 2 deletions(-)
--- a/drivers/scsi/virtio_scsi.c +++ b/drivers/scsi/virtio_scsi.c @@ -631,7 +631,6 @@ static int virtscsi_device_reset(struct return FAILED;
memset(cmd, 0, sizeof(*cmd)); - cmd->sc = sc; cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ .type = VIRTIO_SCSI_T_TMF, .subtype = VIRTIO_SCSI_T_TMF_LOGICAL_UNIT_RESET, @@ -654,7 +653,6 @@ static int virtscsi_abort(struct scsi_cm return FAILED;
memset(cmd, 0, sizeof(*cmd)); - cmd->sc = sc; cmd->req.tmf = (struct virtio_scsi_ctrl_tmf_req){ .type = VIRTIO_SCSI_T_TMF, .subtype = VIRTIO_SCSI_T_TMF_ABORT_TASK,