Re: [Qemu-devel] [PATCH 11/11] qemu/kvm: mark in cpu state that hyper-v crash occured

[Paolo Bonzini <pbonzini@redhat.com>]

On 22/06/2015 18:23, Andreas Färber wrote:
>> > @@ -679,6 +679,7 @@ static const VMStateDescription vmstate_msr_hyperv_crash = {
>> >          VMSTATE_UINT64(env.msr_hv_crash_ctl, X86CPU),
>> >          VMSTATE_UINT64_ARRAY(env.msr_hv_crash_prm,
>> >                               X86CPU, HV_X64_MSR_CRASH_PARAMS),
>> > +        VMSTATE_UINT8(env.hv_crash_occurred, X86CPU),
>> >          VMSTATE_END_OF_LIST()
>> >      }
>> >  };
> This looks like a migration format breakage. You probably need to squash
> it with the preceding patch so that the "cpu/msr_hyperv_crash"
> subsection does not change in size between commits. Just incrementing
> the version is not an option for subsections, I think?

We don't usually care about migration format within the same upstream
release, but yes that would be better.

On the other hand, I wonder if current_cpu is available in
qemu_system_guest_panicked.  If so, you could add the field to the
generic CPUState struct and migrate it as a subsection of
vmstate_cpu_common.

Paolo