Re: [Qemu-devel] [PATCH 0/2] virtio: revert virtio_queue_set_notification() nesting

[Richard Henderson]

On 01/12/2017 03:46 AM, Stefan Hajnoczi wrote:
> The virtio_queue_set_notification() nesting introduced for AioContext polling
> raised an assertion with virtio-net (even in non-polling mode).  Converting
> virtio-net and virtio-crypto to use virtio_queue_set_notification() in a
> nesting fashion would be invasive and isn't worth it.
>
> Patch 1 contains the revert to resolve the bug that Doug noticed.
>
> Patch 2 is a less efficient but safe alternative.
>
> Stefan Hajnoczi (2):
>   Revert "virtio: turn vq->notification into a nested counter"
>   virtio: disable notifications again after poll succeeded
>
>  hw/virtio/virtio.c | 21 +++++++++------------
>  1 file changed, 9 insertions(+), 12 deletions(-)

Tested-by: Richard Henderson <address@hidden>

This problem affected Alpha as well.  I tested the two patches together.


r~