On Mon, May 11, 2020 at 4:33 PM Babu Moger <babu.moger@xxxxxxx> wrote: > > MPK feature is supported by both VMX and SVM. So we can > safely move pkru state save/restore to common code. Also > move all the pkru data structure to kvm_vcpu_arch. > > Also fixes the problem Jim Mattson pointed and suggested below. > > "Though rdpkru and wrpkru are contingent upon CR4.PKE, the PKRU > resource isn't. It can be read with XSAVE and written with XRSTOR. > So, if we don't set the guest PKRU value here(kvm_load_guest_xsave_state), > the guest can read the host value. > > In case of kvm_load_host_xsave_state, guest with CR4.PKE clear could > potentially use XRSTOR to change the host PKRU value" > > Signed-off-by: Babu Moger <babu.moger@xxxxxxx> I would do the bugfix as a separate commit, to ease backporting it to the stable branches.