Re: [PATCH v2 1/3] KVM: x86: implement KVM_{GET|SET}_TSC_STATE

[Thomas Gleixner]

On Tue, Dec 15 2020 at 07:59, Marcelo Tosatti wrote:
> On Fri, Dec 11, 2020 at 10:59:59PM +0100, Paolo Bonzini wrote:
>> So it's still true that the time advances during live migration brownout;
>> 0.1 seconds is just the final part of the live migration process.  But for
>> _live_ migration there is no need to design things according to "people are
>> happy if their clock is off by 0.1 seconds only".  
>
> Agree. What would be a good way to fix this?

None of what's proposed is fixing the underlying problem of wreckaging
CLOCK_REALTIME.

Stop proliferating broken behaviour and please answer the questions I
asked several times now:

   1) Why has the TSC has to restart at the same value?

   2) What is the technical argument that it is correct and acceptable
      to wreckage CLOCK_REALTIME by doing #1?

Thanks,

        tglx