Hi, a similar patch is now in.
Paolo
Il ven 7 ott 2022, 05:26 Vitaly Kuznetsov <vkuzn...@redhat.com> ha scritto:
> Vitaly Kuznetsov <vkuzn...@redhat.com> writes:
>
> > Vitaly Kuznetsov <vkuzn...@redhat.com> writes:
> >
> >> KVM commit c68dc1b577ea ("KVM: x86: Report host tsc and realtime values
> in
> >> KVM_GET_CLOCK") broke migration of certain workloads, e.g. Win11 + WSL2
> >> guest reboots immediately after migration. KVM, however, is not to
> >> blame this time. When KVM_CAP_ADJUST_CLOCK capability is checked, the
> >> result is all supported flags (which the above mentioned KVM commit
> >> enhanced) but kvm_has_adjust_clock_stable() wants it to be
> >> KVM_CLOCK_TSC_STABLE precisely. The result is that 'clock_is_reliable'
> >> is not set in vmstate and the saved clock reading is discarded in
> >> kvmclock_vm_state_change().
> >>
> >> Signed-off-by: Vitaly Kuznetsov <vkuzn...@redhat.com>
> >> ---
> >> target/i386/kvm/kvm.c | 2 +-
> >> 1 file changed, 1 insertion(+), 1 deletion(-)
> >>
> >> diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
> >> index a1fd1f53791d..c33192a87dcb 100644
> >> --- a/target/i386/kvm/kvm.c
> >> +++ b/target/i386/kvm/kvm.c
> >> @@ -157,7 +157,7 @@ bool kvm_has_adjust_clock_stable(void)
> >> {
> >> int ret = kvm_check_extension(kvm_state, KVM_CAP_ADJUST_CLOCK);
> >>
> >> - return (ret == KVM_CLOCK_TSC_STABLE);
> >> + return ret & KVM_CLOCK_TSC_STABLE;
> >> }
> >>
> >> bool kvm_has_adjust_clock(void)
> >
> > Ping) This issue seems to introduce major migration issues with KVM >=
> v5.16
>
> Ping)
>
> --
> Vitaly
>
>
