On Thu, Jun 03, 2021 at 01:48:33PM +0200, Vitaly Kuznetsov wrote: > According to TLFS, Hyper-V guest is supposed to check > HV_HYPERCALL_AVAILABLE privilege bit before accessing > HV_X64_MSR_GUEST_OS_ID/HV_X64_MSR_HYPERCALL MSRs but at least some > Windows versions ignore that. As KVM is very permissive and allows > accessing these MSRs unconditionally, no issue is observed. We may, > however, want to tighten the checks eventually. Conforming to the > spec is probably also a good idea. > > Enable HV_HYPERCALL_AVAILABLE bit unconditionally. > > Signed-off-by: Vitaly Kuznetsov <[email protected]>
Reviewed-by: Eduardo Habkost <[email protected]> -- Eduardo
