Re: [PATCH 1/2] KVM: KVM-on-hyperv: shorten no-entry section on reenlightenment
From: Paolo Bonzini
Date: Thu Aug 12 2021 - 11:53:27 EST
On 11/08/21 20:03, Marcelo Tosatti wrote:
hyperv_stop_tsc_emulation();
/* TSC frequency always matches when on Hyper-V */
for_each_present_cpu(cpu)
per_cpu(cpu_tsc_khz, cpu) = tsc_khz;
kvm_max_guest_tsc_khz = tsc_khz;
Yeah, it's more complicated than this. The right sequence is:
- update the master clock
- update the TSC page parameters
- stop TSC emulation
There is no need to invalidate the TSC page.
Related to this, after kvm_hv_invalidate_tsc_page the sequence value in
the Hyper-V TSC page will always be 1, which is wrong. I'll take a look
at that too.
Paolo