On 12/15/2016 11:52 AM, Dr. David Alan Gilbert wrote:
>> We got a bugreport with this log for a live migration target.
>>
>> 2016-12-13T18:59:03.647309Z qemu-system-s390x: VQ 1 size 0x100 <
>> last_avail_idx 0x2f76 - used_idx 0x762f
> Is this actually an endian problem - 2f76 vs 762f ?
>
> Dave
>
Thanks! It seems you are right:
static inline uint16_t vring_avail_idx(VirtQueue *vq)
{
hwaddr pa;
pa = vq->vring.avail + offsetof(VRingAvail, idx);
vq->shadow_avail_idx = virtio_lduw_phys(vq->vdev, pa);
we should have an endiannes handling here before assigning shadow_avail_idx I
guess
return vq->shadow_avail_idx;
}
I will meditate a bit more on this and probably create a patch to fix it.
What make me wonder is that according to the reports live migration usually
works (ca 1% fails)...
Can I credit you as reporter in case I end up making a fix?
Halil
