[PATCH v8 3/7] KVM: x86: Fix potential race in KVM_GET_CLOCK

[Marcelo Tosatti]

On Thu, Sep 16, 2021 at 06:15:34PM +0000, Oliver Upton wrote:
> Sean noticed that KVM_GET_CLOCK was checking kvm_arch.use_master_clock
> outside of the pvclock sync lock. This is problematic, as the clock
> value written to the user may or may not actually correspond to a stable
> TSC.
> 
> Fix the race by populating the entire kvm_clock_data structure behind
> the pvclock_gtod_sync_lock.
> 
> Suggested-by: Sean Christopherson <seanjc at google.com>
> Signed-off-by: Oliver Upton <oupton at google.com>

ACK patches 1-3, still reviewing the remaining ones...