In addition to handling IO in vcpu thread and
in io thread, blk dataplane introduces yet another mode:
handling it by aio.
This reuses the same handler as previous modes,
which triggers races as these were not designed to be reentrant.
As a temporary fix, use a separate handler just for aio, and
On 29/03/2016 15:42, Michael S. Tsirkin wrote:
> @@ -262,6 +274,7 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
>
> /* Stop notifications for new requests from guest */
> virtio_queue_aio_set_host_notifier_handler(s->vq, s->ctx, false, false);
I think that this should h
On Tue, Mar 29, 2016 at 03:56:18PM +0200, Paolo Bonzini wrote:
>
>
> On 29/03/2016 15:42, Michael S. Tsirkin wrote:
> > @@ -262,6 +274,7 @@ void virtio_blk_data_plane_stop(VirtIOBlockDataPlane *s)
> >
> > /* Stop notifications for new requests from guest */
> > virtio_queue_aio_set_ho
On 29/03/2016 15:58, Michael S. Tsirkin wrote:
> In that case, we'll have to also change scsi to use the new API.
> A bit more work, to be sure.
> Does scsi have the same problem as blk?
Yes. The bug is in the virtio core.
Paolo
On Tue, Mar 29, 2016 at 04:05:46PM +0200, Paolo Bonzini wrote:
>
>
> On 29/03/2016 15:42, Michael S. Tsirkin wrote:
> > +if (s->dataplane) {
> > +/* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so
> > start
> > + * dataplane here instead of waiting for .set_statu
On 29/03/2016 15:42, Michael S. Tsirkin wrote:
> +if (s->dataplane) {
> +/* Some guests kick before setting VIRTIO_CONFIG_S_DRIVER_OK so start
> + * dataplane here instead of waiting for .set_status().
> + */
> +if (!s->dataplane_started) {
> +virti
On 29/03/2016 16:09, Michael S. Tsirkin wrote:
>> > Another small comment, this can be written simply as
>> >
>> > if (s->dataplane) {
>> > virtio_blk_data_plane_start(s->dataplane);
>
> True, it's best not to poke at dataplane_started.
>
> > } else {
> > virtio_blk_han
