On 27/01/20 16:38, Vitaly Kuznetsov wrote: >>> If there are no objections and if we still think it would be beneficial >>> to minimize the list of controls we filter out (and not go with the full >>> set like my RFC suggests), I'll prepare v2. (v1, actually, this was RFC). >> One last idea, can we keep the MSR filtering as is and add the hack in >> vmx_restore_control_msr()? That way the (userspace) host and guest see >> the same values when reading the affected MSRs, and eVMCS wouldn't need >> it's own hook to do consistency checks. > Yes but (if I'm not mistaken) we'll have then to keep the filtering we > currently do in nested_enable_evmcs(): if userspace doesn't do > KVM_SET_MSR for VMX MSRs (QEMU<4.2) then the filtering in > vmx_restore_control_msr() won't happen and the guest will see the > unfiltered set of controls... > Indeed. The place you used in the RFC is the best we can do, I am afraid. Paolo
