virtio_scsi: fix race on device removal (e67423c7) · Commits · 戴 / test

We cancel event work on device removal, but an interrupt could trigger immediately after this, and queue it again. To fix, set a flag. Loosely based on patch by Paolo Bonzini Signed-off-by:

Paolo Bonzini <pbonzini@redhat.com> Signed-off-by:

Michael S. Tsirkin <mst@redhat.com> Signed-off-by:

Rusty Russell <rusty@rustcorp.com.au>

drivers/scsi/virtio_scsi.c

+10 −1

Original line number	Diff line number	Diff line
		@@ -110,6 +110,9 @@ struct virtio_scsi {
		/* CPU hotplug notifier */
		struct notifier_block nb;

		/* Protected by event_vq lock */
		bool stop_events;

		struct virtio_scsi_vq ctrl_vq;
		struct virtio_scsi_vq event_vq;
		struct virtio_scsi_vq req_vqs[];
		@@ -303,6 +306,11 @@ static void virtscsi_cancel_event_work(struct virtio_scsi *vscsi)
		{
		int i;

		/* Stop scheduling work before calling cancel_work_sync. */
		spin_lock_irq(&vscsi->event_vq.vq_lock);
		vscsi->stop_events = true;
		spin_unlock_irq(&vscsi->event_vq.vq_lock);

		for (i = 0; i < VIRTIO_SCSI_EVENT_LEN; i++)
		cancel_work_sync(&vscsi->event_list[i].work);
		}
		@@ -390,6 +398,7 @@ static void virtscsi_complete_event(struct virtio_scsi vscsi, void buf)
		{
		struct virtio_scsi_event_node *event_node = buf;

		if (!vscsi->stop_events)
		queue_work(system_freezable_wq, &event_node->work);
		}

Admin message