On 15/10/19 10:39, Suleiman Souhlal wrote: > I think we have that already (pvtk->flags). > I'll change the if statement above to use pvtk instead of pv_timekeeper. Of course, thanks. >>> +kvm_hostclock_init(void) >>> +{ >>> + unsigned long pa; >>> + >>> + pa = __pa(&pv_timekeeper); >>> + wrmsrl(MSR_KVM_TIMEKEEPER_EN, pa); >> >> >> As Vitaly said, a new CPUID bit must be defined in >> Documentation/virt/kvm/cpuid.txt, and used here. Also please make bit 0 >> an enable bit. > > I think I might not be able to move the enable bit to 0 because we > need the generation count (pvclock_timekeeper.gen) to be the first > word of the struct due to the way we copy the data to userspace, > similarly to how kvm_setup_pvclock_page() does it. I mean bit 0 of the MSR. Thanks, Paolo