On 22/05/2024 01:17, David Woodhouse wrote:
From: David Woodhouse <dwmw@xxxxxxxxxxxx> Both kvm_track_tsc_matching() and pvclock_update_vm_gtod_copy() make a decision about whether the KVM clock should be in master clock mode. They use *different* criteria for the decision though. This isn't really a problem; it only has the potential to cause unnecessary invocations of KVM_REQ_MASTERCLOCK_UPDATE if the masterclock was disabled due to TSC going backwards, or the guest using the old MSR. But it isn't pretty. Factor the decision out to a single function. And document the historical reason why it's disabled for guests that use the old MSR_KVM_SYSTEM_TIME. Signed-off-by: David Woodhouse <dwmw@xxxxxxxxxxxx> --- arch/x86/kvm/x86.c | 27 +++++++++++++++++++++++---- 1 file changed, 23 insertions(+), 4 deletions(-)
Reviewed-by: Paul Durrant <paul@xxxxxxx>