From: David Woodhouse <dwmw@xxxxxxxxxxxx>
Commit d98d07ca7e034 ("KVM: x86: update pvclock area conditionally, on
cpu migration") turned an unconditional KVM_REQ_CLOCK_UPDATE into a
conditional one, if either the master clock isn't enabled *or* the vCPU
was not previously scheduled (vcpu->cpu == -1). The commit message doesn't
explain the latter condition, which is specifically for the master clock
case.
Commit 0061d53daf26f ("KVM: x86: limit difference between kvmclock
updates") later turned that into a KVM_REQ_GLOBAL_CLOCK_UPDATE to avoid
skew between vCPUs.
In master clock mode there is no need for any of that, regardless of
whether/where this vCPU was previously scheduled.
Do it only if (!kvm->arch.use_master_clock).
Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx>
---
arch/x86/kvm/x86.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 32a873d5ed00..dd53860ca284 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -5161,7 +5161,7 @@ void kvm_arch_vcpu_load(struct kvm_vcpu *vcpu, int cpu)
* On a host with synchronized TSC, there is no need to update
* kvmclock on vcpu->cpu migration
*/
- if (!vcpu->kvm->arch.use_master_clock || vcpu->cpu == -1)
+ if (!vcpu->kvm->arch.use_master_clock)
kvm_make_request(KVM_REQ_GLOBAL_CLOCK_UPDATE, vcpu);
if (vcpu->cpu != cpu)
kvm_make_request(KVM_REQ_MIGRATE_TIMER, vcpu);
--
2.44.0
