4.15-stable review patch. If anyone has any objections, please let me know.
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From: Uma Krishnan ukrishn@linux.vnet.ibm.com
commit 96cf727fe8f102bf92150b741db71ee39fb8c521 upstream.
In the event of a command failure, cxlflash returns the failure to the upper layers to process. After processing the error, when the command is queued again, the private command structure will not be zeroed and the ioasc could be stale. Per the SISLite specification, the AFU only sets the ioasc in the presence of a failure. Thus, even though the original command succeeds the second time, the command is considered a failure due to stale ioasc. This cycle repeats indefinitely and can cause a hang or IO failure.
To fix the issue, clear the ioasc before queuing any command.
[mkp: added Cc: stable per request]
Fixes: 479ad8e9d48c ("scsi: cxlflash: Remove zeroing of private command data") Signed-off-by: Uma Krishnan ukrishn@linux.vnet.ibm.com Acked-by: Matthew R. Ochs mrochs@linux.vnet.ibm.com Signed-off-by: Martin K. Petersen martin.petersen@oracle.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org
--- drivers/scsi/cxlflash/main.c | 1 + 1 file changed, 1 insertion(+)
--- a/drivers/scsi/cxlflash/main.c +++ b/drivers/scsi/cxlflash/main.c @@ -620,6 +620,7 @@ static int cxlflash_queuecommand(struct cmd->parent = afu; cmd->hwq_index = hwq_index;
+ cmd->sa.ioasc = 0; cmd->rcb.ctx_id = hwq->ctx_hndl; cmd->rcb.msi = SISL_MSI_RRQ_UPDATED; cmd->rcb.port_sel = CHAN2PORTMASK(scp->device->channel);