1 files changed, 4 insertions, 10 deletions

diff --git a/hw/scsi/virtio-scsi-dataplane.c b/hw/scsi/virtio-scsi-dataplane.c
index 1e684beebe..2806a121b2 100644
--- a/hw/scsi/virtio-scsi-dataplane.c
+++ b/hw/scsi/virtio-scsi-dataplane.c
@@ -20,7 +20,7 @@
 #include "scsi/constants.h"
 #include "hw/virtio/virtio-bus.h"
 
-/* Context: QEMU global mutex held */
+/* Context: BQL held */
 void virtio_scsi_dataplane_setup(VirtIOSCSI *s, Error **errp)
 {
     VirtIOSCSICommon *vs = VIRTIO_SCSI_COMMON(s);
@@ -93,7 +93,7 @@ static void virtio_scsi_dataplane_stop_bh(void *opaque)
     }
 }
 
-/* Context: QEMU global mutex held */
+/* Context: BQL held */
 int virtio_scsi_dataplane_start(VirtIODevice *vdev)
 {
     int i;
@@ -149,23 +149,17 @@ int virtio_scsi_dataplane_start(VirtIODevice *vdev)
 
     memory_region_transaction_commit();
 
-    /*
-     * These fields are visible to the IOThread so we rely on implicit barriers
-     * in aio_context_acquire() on the write side and aio_notify_accept() on
-     * the read side.
-     */
     s->dataplane_starting = false;
     s->dataplane_started = true;
+    smp_wmb(); /* paired with aio_notify_accept() */
 
     if (s->bus.drain_count == 0) {
-        aio_context_acquire(s->ctx);
         virtio_queue_aio_attach_host_notifier(vs->ctrl_vq, s->ctx);
         virtio_queue_aio_attach_host_notifier_no_poll(vs->event_vq, s->ctx);
 
         for (i = 0; i < vs->conf.num_queues; i++) {
             virtio_queue_aio_attach_host_notifier(vs->cmd_vqs[i], s->ctx);
         }
-        aio_context_release(s->ctx);
     }
     return 0;
 
@@ -191,7 +185,7 @@ fail_guest_notifiers:
     return -ENOSYS;
 }
 
-/* Context: QEMU global mutex held */
+/* Context: BQL held */
 void virtio_scsi_dataplane_stop(VirtIODevice *vdev)
 {
     BusState *qbus = qdev_get_parent_bus(DEVICE(vdev));