On Thu, Aug 29, 2024, Borislav Petkov wrote: > On Fri, Aug 16, 2024 at 12:37:52PM -0700, Sean Christopherson wrote: > > I would strongly prefer to enumerate this in /proc/cpuinfo, having to manually > > query CPUID to see if a CPU supports a feature I want to test is beyond annoying. > > Why? > > We have tools/arch/x86/kcpuid/kcpuid.c for that. Ah, sorry, if the platform+kernel supports the feature, not just raw CPU. And because that utility is not available by default on most targets I care about, and having to build and copy over a binary is annoying (though this is a minor gripe). That said, what I really want in most cases is to know if _KVM_ supports a feature. I'll think more on this, I have a few vague ideas for getting a pile of information out of KVM without needing to add more uABI.