[lkml]   [2007]   [Dec]   [19]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: [kvm-devel] Guest kernel hangs in smp kvm for older kernels prior to tsc sync cleanup
Ingo Molnar wrote:
> * Avi Kivity <> wrote:
>> Avi Kivity wrote:
>>> Testing shows wrmsr and rdtsc function normally.
>>> I'll try pinning the vcpus to cpus and see if that helps.
>> It does.
> do we let the guest read the physical CPU's TSC? That would be trouble.

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.

error compiling committee.c: too many arguments to function

 \ /
  Last update: 2007-12-19 15:31    [from the cache]
©2003-2014 Jasper Spaans. hosted at Digital Ocean