Messages in this thread | | | Subject | Re: [PATCH v11 7/7] KVM: x86: virtualize cpuid faulting | From | Nadav Amit <> | Date | Fri, 11 Nov 2016 12:54:46 -0800 |
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> 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).
Nadav
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