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Date:   Mon, 7 Aug 2023 09:03:12 +0200
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Subject: Re: [PATCH v5 11/19] KVM:VMX: Emulate read and write to CET MSRs
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To:     Sean Christopherson <seanjc@google.com>
Cc:     Chao Gao <chao.gao@intel.com>,
        Yang Weijiang <weijiang.yang@intel.com>, peterz@infradead.org,
        john.allen@amd.com, kvm@vger.kernel.org,
        linux-kernel@vger.kernel.org, rick.p.edgecombe@intel.com,
        binbin.wu@linux.intel.com
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From:   Paolo Bonzini <pbonzini@redhat.com>
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On 8/5/23 00:21, Sean Christopherson wrote:
> Oooh, the MSRs that don't exempt host_initiated are added to the list

(are *not* added)

> of MSRs to save/restore, i.e. KVM "silently" supports 
> MSR_AMD64_OSVW_ID_LENGTH and MSR_AMD64_OSVW_STATUS.
> 
> And guest_pv_has() returns true unless userspace has opted in to
> enforcement.

Two different ways of having the same bug.  The latter was introduced in 
the implementation of KVM_CAP_ENFORCE_PV_FEATURE_CPUID; it would become 
a problem if some selftests started using it.

Paolo