On Tue, Jul 31, 2018 at 9:00 AM Paolo Bonzini <pbonz...@redhat.com> wrote: > > On 31/07/2018 14:57, tedheadster wrote: > >> > >> This shouldn't be necessary; for systems that don't have virtualization > >> extensions, the comment explains why setting X86_FEATURE_VMMCALL is safe. > >> > >> But it is also wrong, because you can run a 32-bit kernel as a guest on > >> a 64-bit processor, and then it should set X86_FEATURE_VMMCALL because > >> the processor has the vmmcall instruction and not Intel's vmcall. > >> > > > > Paolo, > > I'm running this on a bare metal machine (no virtualization) with a > > 32-bit AMD i486 class cpu. Should the feature be showing up in > > /proc/cpuinfo under the 'flags' line? It does on my machine, and it > > looked wrong to me. > > It's a bit silly, but it's not particularly wrong.
Why is there even a specific feature flag for VMMCALL? Isn't X86_FEATURE_SVM sufficient to differentiate which opcode to use? -- Brian Gerst
