Messages in this thread | | | Date | Fri, 15 Sep 2023 11:52:35 -0500 | Subject | Re: [PATCH 1/2] KVM: SVM: Fix TSC_AUX virtualization setup | From | Tom Lendacky <> |
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On 9/14/23 15:48, Tom Lendacky wrote: > On 9/14/23 15:28, Sean Christopherson wrote: >> On Thu, Sep 14, 2023, Tom Lendacky wrote:
> >> >>> + if (guest_cpuid_has(vcpu, X86_FEATURE_RDTSCP)) >>> + svm_clr_intercept(svm, INTERCEPT_RDTSCP); >> >> Same thing here. > > Will do.
For RDTSCP, svm_recalc_instruction_intercepts() will set/clear the RDTSCP intercept as part of the svm_vcpu_set_after_cpuid() path, but it will only do it based on kvm_cpu_cap_has(X86_FEATURE_RDTSCP) being true, which is very likely.
Do you think that is good enough and we can drop the setting and clearing of the RDTSCP intercept in the sev_es_vcpu_set_after_cpuid() function and only deal with the TSC_AUX MSR intercept?
On a side note, it looks like RDTSCP would not be intercepted if the KVM cap X86_FEATURE_RDTSCP feature is cleared, however unlikely, in kvm_set_cpu_caps() and RDTSCP is not advertised to the guest (assuming the guest is ignoring the RDTSCP CPUID bit).
Thanks, Tom
> > Thanks, > Tom > >> >>> + } >>> +}
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