On Thu, Oct 08, 2015 at 10:51:02PM +0200, Steffen Bauch wrote:
>
>
> On 10/08/2015 05:32 PM, Nikita Kalyazin wrote:
> >Hi Yuanhan,
> >
> >
> >As I understand, the dead loop happened here (virtio_send_command):
> >while (vq->vq_used_cons_idx == vq->vq_ring.used->idx) {
> > rte_rmb();
> > usleep(100);
> >}
> >
> >Could you explain why wrong config reading caused that and how correct
> >reading helps to avoid?
Wrong config reading results to wrong config->max_virtqueue_pairs, which
ends up with wrong ctrl vq index being set:
PMD: virtio_send_command(): vq->vq_queue_index = 37120
Note that you need enable CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_INIT to see above
debug log.
That is to say we are waiting for the backend to consume a non-exist
queue, and that's how the dead loop comes.
> >
> Hi,
>
> I just recognized that this dead loop is the same one that I have
> experienced (see
> http://dpdk.org/ml/archives/dev/2015-October/024737.html for
> reference). Just applying the changes in this patch (only 07/12)
> will not fix the dead loop at least in my setup.
Try to enable CONFIG_RTE_LIBRTE_VIRTIO_DEBUG_INIT, and dump more log?
--yliu
