Messages in this thread | | | From | Kyle Huey <> | Date | Wed, 16 Nov 2016 08:40:09 -0800 | Subject | Re: [PATCH v11 7/7] KVM: x86: virtualize cpuid faulting |
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On Fri, Nov 11, 2016 at 12:54 PM, Nadav Amit <nadav.amit@gmail.com> wrote: > >> On Nov 10, 2016, at 3:40 PM, Kyle Huey <me@kylehuey.com> wrote: >> >> Hardware support for faulting on the cpuid instruction is not required to >> emulate it, because cpuid triggers a VM exit anyways. KVM handles the relevant >> MSRs (MSR_PLATFORM_INFO and MSR_MISC_FEATURES_ENABLE) and upon a >> cpuid-induced VM exit checks the cpuid faulting state and the CPL. >> kvm_require_cpl is even kind enough to inject the GP fault for us. > > I think that for consistency you should also revise em_cpuid() of KVM > instruction emulator. Otherwise it may be a potential security > hazard (as far fetched as it currently seems).
Hmm, ok. Do you know how I can test this code path?
- Kyle
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