On 5/12/20 11:39 AM, Jim Mattson wrote: > 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. Ok. Sure.
