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) -- 2.37.3