Re: [kvm-devel] Guest kernel hangs in smp kvm for older kernelspriorto tsc sync cleanup

[Avi Kivity]

Dor Laor wrote:
> > > >
> > > > vmx (and svm) allow us to add an offset to the physical tsc.  We 
> > set it
> > > > on startup to -tsc (so that an rdtsc on boot would return 0), and
> > > > massage it on vcpu migration so that guest rdtsc is monotonic.
> > > >
> > > > The net effect is that tsc on a vcpu can experience large forward 
> > jumps
> > > > and changes in rate, but no negative jumps.
> > >
> > > Changes in rate does not sound good. It's possibly what's screwing up
> > > my paravirt clock implementation in smp.
> >
> > Do you mean in the case of VM migration, or just starting them on a 
> > single
> > host?
> It's the cpu preemption stuff on local host and not VM migration

No, migrating a vcpu to another cpu.

--
error compiling committee.c: too many arguments to function

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