Re: [Qemu-devel] E5-2620v2 - emulation stop error

Andrey Korolyov
2015-04-01T15:38:10Z

On Wed, Apr 1, 2015 at 4:19 PM, Paolo Bonzini <pbonzini@redhat.com> wrote:
>
>
> On 01/04/2015 14:26, Andrey Korolyov wrote:
>> Yes, I disabled host watchdog during runtime. Indeed guest-induced NMI
>> would look different and they had no reasons to be fired at this stage
>> inside guest. I`d suspect a hypervisor hardware misbehavior there but
>> have a very little idea on how APICv behavior (which is completely
>> microcode-dependent and CPU-dependent but decoupled from peripheral
>> hardware) may vary at this point, I am using 1.20140913.1 ucode
>> version from debian if this can matter. Will send trace suggested by
>> Paolo in a next couple of hours. Also it would be awesome to ask
>> hardware folks from Intel who can prove or disprove my abovementioned
>> statement (as I was unable to catch the problem on 2603v2 so far, this
>> hypothesis has some chance to be real).
>
> Yes, the interaction with the NMI watchdog is unexpected and makes a
> processor erratum somewhat more likely.
>
> Paolo

http://xdel.ru/downloads/kvm-e5v2-issue/trace-nmi-apicv-fail-at-reboot.dat.gz

err, no NMI entries nearby failure event, though capture should be correct:
/sys/kernel/debug/tracing/events/kvm*/filter
/sys/kernel/debug/tracing/events/*/kvm*/filter
/sys/kernel/debug/tracing/events/nmi*/filter
/sys/kernel/debug/tracing/events/*/nmi*/filter