| From 0cf9135b773bf32fba9dd8e6699c1b331ee4b749 Mon Sep 17 00:00:00 2001 |
| From: Sean Christopherson <sean.j.christopherson@intel.com> |
| Date: Thu, 7 Mar 2019 15:43:02 -0800 |
| Subject: KVM: x86: Emulate MSR_IA32_ARCH_CAPABILITIES on AMD hosts |
| |
| From: Sean Christopherson <sean.j.christopherson@intel.com> |
| |
| commit 0cf9135b773bf32fba9dd8e6699c1b331ee4b749 upstream. |
| |
| The CPUID flag ARCH_CAPABILITIES is unconditioinally exposed to host |
| userspace for all x86 hosts, i.e. KVM advertises ARCH_CAPABILITIES |
| regardless of hardware support under the pretense that KVM fully |
| emulates MSR_IA32_ARCH_CAPABILITIES. Unfortunately, only VMX hosts |
| handle accesses to MSR_IA32_ARCH_CAPABILITIES (despite KVM_GET_MSRS |
| also reporting MSR_IA32_ARCH_CAPABILITIES for all hosts). |
| |
| Move the MSR_IA32_ARCH_CAPABILITIES handling to common x86 code so |
| that it's emulated on AMD hosts. |
| |
| Fixes: 1eaafe91a0df4 ("kvm: x86: IA32_ARCH_CAPABILITIES is always supported") |
| Cc: stable@vger.kernel.org |
| Reported-by: Xiaoyao Li <xiaoyao.li@linux.intel.com> |
| Cc: Jim Mattson <jmattson@google.com> |
| Signed-off-by: Sean Christopherson <sean.j.christopherson@intel.com> |
| Signed-off-by: Paolo Bonzini <pbonzini@redhat.com> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| arch/x86/include/asm/kvm_host.h | 1 + |
| arch/x86/kvm/vmx.c | 14 -------------- |
| arch/x86/kvm/x86.c | 12 ++++++++++++ |
| 3 files changed, 13 insertions(+), 14 deletions(-) |
| |
| --- a/arch/x86/include/asm/kvm_host.h |
| +++ b/arch/x86/include/asm/kvm_host.h |
| @@ -509,6 +509,7 @@ struct kvm_vcpu_arch { |
| bool tpr_access_reporting; |
| u64 ia32_xss; |
| u64 microcode_version; |
| + u64 arch_capabilities; |
| |
| /* |
| * Paging state of the vcpu |
| --- a/arch/x86/kvm/vmx.c |
| +++ b/arch/x86/kvm/vmx.c |
| @@ -740,7 +740,6 @@ struct vcpu_vmx { |
| u64 msr_guest_kernel_gs_base; |
| #endif |
| |
| - u64 arch_capabilities; |
| u64 spec_ctrl; |
| |
| u32 vm_entry_controls_shadow; |
| @@ -3493,12 +3492,6 @@ static int vmx_get_msr(struct kvm_vcpu * |
| |
| msr_info->data = to_vmx(vcpu)->spec_ctrl; |
| break; |
| - case MSR_IA32_ARCH_CAPABILITIES: |
| - if (!msr_info->host_initiated && |
| - !guest_cpuid_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES)) |
| - return 1; |
| - msr_info->data = to_vmx(vcpu)->arch_capabilities; |
| - break; |
| case MSR_IA32_SYSENTER_CS: |
| msr_info->data = vmcs_read32(GUEST_SYSENTER_CS); |
| break; |
| @@ -3663,11 +3656,6 @@ static int vmx_set_msr(struct kvm_vcpu * |
| vmx_disable_intercept_for_msr(vmx->vmcs01.msr_bitmap, MSR_IA32_PRED_CMD, |
| MSR_TYPE_W); |
| break; |
| - case MSR_IA32_ARCH_CAPABILITIES: |
| - if (!msr_info->host_initiated) |
| - return 1; |
| - vmx->arch_capabilities = data; |
| - break; |
| case MSR_IA32_CR_PAT: |
| if (vmcs_config.vmentry_ctrl & VM_ENTRY_LOAD_IA32_PAT) { |
| if (!kvm_mtrr_valid(vcpu, MSR_IA32_CR_PAT, data)) |
| @@ -5929,8 +5917,6 @@ static int vmx_vcpu_setup(struct vcpu_vm |
| ++vmx->nmsrs; |
| } |
| |
| - vmx->arch_capabilities = kvm_get_arch_capabilities(); |
| - |
| vm_exit_controls_init(vmx, vmcs_config.vmexit_ctrl); |
| |
| /* 22.2.1, 20.8.1 */ |
| --- a/arch/x86/kvm/x86.c |
| +++ b/arch/x86/kvm/x86.c |
| @@ -2234,6 +2234,11 @@ int kvm_set_msr_common(struct kvm_vcpu * |
| if (msr_info->host_initiated) |
| vcpu->arch.microcode_version = data; |
| break; |
| + case MSR_IA32_ARCH_CAPABILITIES: |
| + if (!msr_info->host_initiated) |
| + return 1; |
| + vcpu->arch.arch_capabilities = data; |
| + break; |
| case MSR_EFER: |
| return set_efer(vcpu, data); |
| case MSR_K7_HWCR: |
| @@ -2523,6 +2528,12 @@ int kvm_get_msr_common(struct kvm_vcpu * |
| case MSR_IA32_UCODE_REV: |
| msr_info->data = vcpu->arch.microcode_version; |
| break; |
| + case MSR_IA32_ARCH_CAPABILITIES: |
| + if (!msr_info->host_initiated && |
| + !guest_cpuid_has(vcpu, X86_FEATURE_ARCH_CAPABILITIES)) |
| + return 1; |
| + msr_info->data = vcpu->arch.arch_capabilities; |
| + break; |
| case MSR_MTRRcap: |
| case 0x200 ... 0x2ff: |
| return kvm_mtrr_get_msr(vcpu, msr_info->index, &msr_info->data); |
| @@ -7918,6 +7929,7 @@ int kvm_arch_vcpu_setup(struct kvm_vcpu |
| { |
| int r; |
| |
| + vcpu->arch.arch_capabilities = kvm_get_arch_capabilities(); |
| kvm_vcpu_mtrr_init(vcpu); |
| r = vcpu_load(vcpu); |
| if (r) |