Re: [Qemu-devel] Regression on KVM qemu-system-aarch64 since "monitor: enable IO thread for (qmp & !mux) typed"

[Auger Eric <eric.auger@redhat.com>]

Hi Peter,

On 23/03/18 13:19, Peter Xu wrote:
> On Fri, Mar 23, 2018 at 01:01:43PM +0100, Auger Eric wrote:
>> Hi,
>>
>> On 23/03/18 11:26, Peter Maydell wrote:
>>> On 23 March 2018 at 10:24, Auger Eric <eric.auger@redhat.com> wrote:
>>>> Hi,
>>>>
>>>> I observe a regression on KVM accelerated qemu-system-aarch64:
>>>>
>>>> Unexpected error in kvm_device_access() at
>>>> /home/augere/UPSTREAM/qemu/accel/kvm/kvm-all.c:2164:
>>>> 2018-03-23T09:59:59.629439Z qemu-system-aarch64: KVM_GET_DEVICE_ATTR
>>>> failed: Group 6 attr 0x000000000000c664: Device or resource busy
>>>> 2018-03-23 10:00:00.085+0000: shutting down, reason=crashed
>>>
>>> Can you get a backtrace for this? (I guess you'd need to fiddle
>>> with the kvm_device_access() code to make it assert rather
>>> than passing back the error).
>>
>> OK. I will try to do so. As I could have expected, I cannot reproduce on
>> a standalone qemu command line. The problem observed above is seen with
>> libvirt launch which may be doing some other QMP stuff concurrently?
> 
> Maybe not concurrently inside libvirt, but after the patches AFAIK the
> QMP part can be concurrent with something else or break some timing.
> 
> Anyway, sorry for that!  I'll see what I can do to help.

No worries

Thanks

Eric
>