Re: [PATCH v14 07/13] KVM: VMX: Emulate reads and writes to CET MSRs

From: Paolo Bonzini
Date: Thu Jan 28 2021 - 12:49:26 EST


On 06/11/20 02:16, Yang Weijiang wrote:

+static bool cet_is_ssp_msr_accessible(struct kvm_vcpu *vcpu,
+ struct msr_data *msr)
+{
+ u64 mask;
+
+ if (!kvm_cet_supported())
+ return false;
+
+ if (msr->host_initiated)
+ return true;
+
+ if (!guest_cpuid_has(vcpu, X86_FEATURE_SHSTK))
+ return false;
+
+ if (msr->index == MSR_IA32_INT_SSP_TAB)
+ return false;

Shouldn't this return true?

Paolo

+ mask = (msr->index == MSR_IA32_PL3_SSP) ? XFEATURE_MASK_CET_USER :
+ XFEATURE_MASK_CET_KERNEL;
+ return !!(vcpu->arch.guest_supported_xss & mask);
+}