From: Brian King brking@linux.vnet.ibm.com
commit e20f80b9b163dc402dca115eed0affba6df5ebb5 upstream.
Commit a264cf5e81c7 ("scsi: ibmvfc: Fix command state accounting and stale response detection") introduced a regression in detecting duplicate responses. This was observed in test where a command was sent to the VIOS and completed before ibmvfc_send_event() set the active flag to 1, which resulted in the atomic_dec_if_positive() call in ibmvfc_handle_crq() thinking this was a duplicate response, which resulted in scsi_done() not getting called, so we then hit a SCSI command timeout for this command once the timeout expires. This simply ensures the active flag gets set prior to making the hcall to send the command to the VIOS, in order to close this window.
Link: https://lore.kernel.org/r/20211019152129.16558-1-brking@linux.vnet.ibm.com Fixes: a264cf5e81c7 ("scsi: ibmvfc: Fix command state accounting and stale response detection") Cc: stable@vger.kernel.org Acked-by: Tyrel Datwyler tyreld@linux.ibm.com Signed-off-by: Brian King brking@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/ibmvscsi/ibmvfc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
--- a/drivers/scsi/ibmvscsi/ibmvfc.c +++ b/drivers/scsi/ibmvscsi/ibmvfc.c @@ -1696,6 +1696,7 @@ static int ibmvfc_send_event(struct ibmv
spin_lock_irqsave(&evt->queue->l_lock, flags); list_add_tail(&evt->queue_list, &evt->queue->sent); + atomic_set(&evt->active, 1);
mb();
@@ -1710,6 +1711,7 @@ static int ibmvfc_send_event(struct ibmv be64_to_cpu(crq_as_u64[1]));
if (rc) { + atomic_set(&evt->active, 0); list_del(&evt->queue_list); spin_unlock_irqrestore(&evt->queue->l_lock, flags); del_timer(&evt->timer); @@ -1737,7 +1739,6 @@ static int ibmvfc_send_event(struct ibmv
evt->done(evt); } else { - atomic_set(&evt->active, 1); spin_unlock_irqrestore(&evt->queue->l_lock, flags); ibmvfc_trc_start(evt); }