Merge remote-tracking branch 'lsk/v3.10/topic/arm64-cpuidle' into linux-linaro-lsk

[firefly-linux-kernel-4.4.55.git] / drivers / scsi / ibmvscsi / ibmvscsi.c

diff --git a/drivers/scsi/ibmvscsi/ibmvscsi.c b/drivers/scsi/ibmvscsi/ibmvscsi.c
index d0fa4b6c551fd677bfa14252525717cf4f32469d..c62b3e5d44bd9d04dd270259725298505fc2c519 100644 (file)
--- a/drivers/scsi/ibmvscsi/ibmvscsi.c
+++ b/drivers/scsi/ibmvscsi/ibmvscsi.c
@@ -185,6 +185,11 @@ static struct viosrp_crq *crq_queue_next_crq(struct crq_queue *queue)
        if (crq->valid & 0x80) {
                if (++queue->cur == queue->size)
                        queue->cur = 0;
+
+               /* Ensure the read of the valid bit occurs before reading any
+                * other bits of the CRQ entry
+                */
+               rmb();
        } else
                crq = NULL;
        spin_unlock_irqrestore(&queue->lock, flags);
@@ -203,6 +208,11 @@ static int ibmvscsi_send_crq(struct ibmvscsi_host_data *hostdata,
 {
        struct vio_dev *vdev = to_vio_dev(hostdata->dev);
 
+       /*
+        * Ensure the command buffer is flushed to memory before handing it
+        * over to the VIOS to prevent it from fetching any stale data.
+        */
+       mb();
        return plpar_hcall_norets(H_SEND_CRQ, vdev->unit_address, word1, word2);
 }
 
@@ -794,7 +804,8 @@ static void purge_requests(struct ibmvscsi_host_data *hostdata, int error_code)
                                       evt->hostdata->dev);
                        if (evt->cmnd_done)
                                evt->cmnd_done(evt->cmnd);
-               } else if (evt->done)
+               } else if (evt->done && evt->crq.format != VIOSRP_MAD_FORMAT &&
+                          evt->iu.srp.login_req.opcode != SRP_LOGIN_REQ)
                        evt->done(evt);
                free_event_struct(&evt->hostdata->pool, evt);
                spin_lock_irqsave(hostdata->host->host_lock, flags);