From 7a8f7c1f3434afc94b6895eff713e0fcea01e3b4 Mon Sep 17 00:00:00 2001 From: Maxim Levitsky Date: Thu, 19 May 2022 05:27:02 -0500 Subject: [PATCH] KVM: x86: nSVM: always intercept x2apic msrs As a preparation for x2avic, this patch ensures that x2apic msrs are always intercepted for the nested guest. Reviewed-by: Suravee Suthikulpanit Tested-by: Suravee Suthikulpanit Signed-off-by: Maxim Levitsky Message-Id: <20220519102709.24125-11-suravee.suthikulpanit@amd.com> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/svm/nested.c | 5 +++++ arch/x86/kvm/svm/svm.h | 9 +++++++++ 2 files changed, 14 insertions(+) diff --git a/arch/x86/kvm/svm/nested.c b/arch/x86/kvm/svm/nested.c index 83bae1f2eeb8..adf4120b05d9 100644 --- a/arch/x86/kvm/svm/nested.c +++ b/arch/x86/kvm/svm/nested.c @@ -230,6 +230,11 @@ static bool nested_svm_vmrun_msrpm(struct vcpu_svm *svm) break; p = msrpm_offsets[i]; + + /* x2apic msrs are intercepted always for the nested guest */ + if (is_x2apic_msrpm_offset(p)) + continue; + offset = svm->nested.ctl.msrpm_base_pa + (p * 4); if (kvm_vcpu_read_guest(&svm->vcpu, offset, &value, 4)) diff --git a/arch/x86/kvm/svm/svm.h b/arch/x86/kvm/svm/svm.h index 6d89842853cf..288a1384aa0f 100644 --- a/arch/x86/kvm/svm/svm.h +++ b/arch/x86/kvm/svm/svm.h @@ -521,6 +521,15 @@ static inline bool nested_npt_enabled(struct vcpu_svm *svm) return svm->nested.ctl.nested_ctl & SVM_NESTED_CTL_NP_ENABLE; } +static inline bool is_x2apic_msrpm_offset(u32 offset) +{ + /* 4 msrs per u8, and 4 u8 in u32 */ + u32 msr = offset * 16; + + return (msr >= APIC_BASE_MSR) && + (msr < (APIC_BASE_MSR + 0x100)); +} + /* svm.c */ #define MSR_INVALID 0xffffffffU