Re: [Qemu-stable] [PATCH] target-i386: do not read/write MSR_TSC_AUX from KVM if CPUID bit is not set

[Peter Lieven]

Am 31.03.2016 um 18:52 schrieb Paolo Bonzini:
>
> On 31/03/2016 17:38, Peter Lieven wrote:
>>
>>> Am 31.03.2016 um 15:23 schrieb Paolo Bonzini <address@hidden>:
>>>
>>>
>>>
>>>> On 31/03/2016 15:12, Peter Lieven wrote:
>>>>>> KVM does not let you read or write this MSR if the corresponding CPUID
>>>>>> bit is not set.  This in turn causes MSRs that come after MSR_TSC_AUX
>>>>>> to be ignored by KVM_SET_MRSS.
>>>> Is it possible that this causes a freeze when migrating vom qemu 2.2.0
>>>> to 2.5.1?
>>> I wouldn't exclude it if the CPU model is Westmere or earlier.
>> the Host CPU or the Emulated CPU?
> The guest.

I can confirm this seems to fix the migration for emulated Westmere CPUs. 
Regardless if its a 2.2.0 -> 2.5.1 or 2.5.1 -> 2.5.1
migration.

Peter