On 14/11/2016 16:40, Marcelo Tosatti wrote:
> static bool kvmclock_src_use_reliable_get_clock(void *opaque)
> {
> KVMClockState *s = opaque;
>
> /*
> * On machine types that support reliable KVM_GET_CLOCK,
> * if host kernel does provide reliable KVM_GET_CLOCK,
> * set src_use_reliable_get_clock=true so that destination
> * avoids reading kvmclock from memory.
> */
> if (s->mach_use_reliable_get_clock && kvm_has_adjust_clock_stable())
> {
> s->src_use_reliable_get_clock = true;
> }
>
> return s->mach_use_reliable_get_clock;
> }
>
>
> Ah, OK, done.
s->src_use_reliable_get_clock should not be set with
KVM_CHECK_EXTENSION, but rather from the flags returned by KVM_GET_CLOCK.
> So s->src_use_reliable_get_clock is only used to indicate
> to the destination that: "you can use KVM_GET_CLOCK value,
> its safe".
Yes, we agree. I was listing all the points, not just those where we
disagree. Actually I'm not sure where we disagree, except on using
flags from KVM_CHECK_EXTENSION vs. flags from KVM_GET_CLOCK...
Paolo
