linux-kernel - [PATCH 4/6] KVM: x86: Move MSR_IA32_PRED

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20230322011440.2195485-5-seanjc@google.com>
Date:   Tue, 21 Mar 2023 18:14:38 -0700
From:   Sean Christopherson <seanjc@...gle.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Nathan Chancellor <nathan@...nel.org>,
        Emanuele Giuseppe Esposito <eesposit@...hat.com>,
        Pawan Gupta <pawan.kumar.gupta@...ux.intel.com>,
        Jim Mattson <jmattson@...gle.com>
Subject: [PATCH 4/6] KVM: x86: Move MSR_IA32_PRED_CMD WRMSR emulation to
 common code

Dedup the handling of MSR_IA32_PRED_CMD across VMX and SVM by moving the
logic to kvm_set_msr_common().  Now that the MSR interception toggling is
handled as part of setting guest CPUID, the VMX and SVM paths are
identical.

Opportunistically massage the code to make it a wee bit denser.

Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/svm.c | 14 --------------
 arch/x86/kvm/vmx/vmx.c | 14 --------------
 arch/x86/kvm/x86.c     | 11 +++++++++++
 3 files changed, 11 insertions(+), 28 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index f757b436ffae..85bb535fc321 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -2942,20 +2942,6 @@ static int svm_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr)
 		 */
 		set_msr_interception(vcpu, svm->msrpm, MSR_IA32_SPEC_CTRL, 1, 1);
 		break;
-	case MSR_IA32_PRED_CMD:
-		if (!msr->host_initiated &&
-		    !guest_has_pred_cmd_msr(vcpu))
-			return 1;
-
-		if (data & ~PRED_CMD_IBPB)
-			return 1;
-		if (!boot_cpu_has(X86_FEATURE_IBPB))
-			return 1;
-		if (!data)
-			break;
-
-		wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB);
-		break;
 	case MSR_AMD64_VIRT_SPEC_CTRL:
 		if (!msr->host_initiated &&
 		    !guest_cpuid_has(vcpu, X86_FEATURE_VIRT_SSBD))
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index 5c01c76c0d45..29807be219b9 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -2285,20 +2285,6 @@ static int vmx_set_msr(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		if (data & ~(TSX_CTRL_RTM_DISABLE | TSX_CTRL_CPUID_CLEAR))
 			return 1;
 		goto find_uret_msr;
-	case MSR_IA32_PRED_CMD:
-		if (!msr_info->host_initiated &&
-		    !guest_has_pred_cmd_msr(vcpu))
-			return 1;
-
-		if (data & ~PRED_CMD_IBPB)
-			return 1;
-		if (!boot_cpu_has(X86_FEATURE_IBPB))
-			return 1;
-		if (!data)
-			break;
-
-		wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB);
-		break;
 	case MSR_IA32_CR_PAT:
 		if (!kvm_pat_valid(data))
 			return 1;
diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 237c483b1230..c83ec88da043 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3617,6 +3617,17 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		vcpu->arch.perf_capabilities = data;
 		kvm_pmu_refresh(vcpu);
 		return 0;
+	case MSR_IA32_PRED_CMD:
+		if (!msr_info->host_initiated && !guest_has_pred_cmd_msr(vcpu))
+			return 1;
+
+		if (!boot_cpu_has(X86_FEATURE_IBPB) || (data & ~PRED_CMD_IBPB))
+			return 1;
+		if (!data)
+			break;
+
+		wrmsrl(MSR_IA32_PRED_CMD, PRED_CMD_IBPB);
+		break;
 	case MSR_EFER:
 		return set_efer(vcpu, msr_info);
 	case MSR_K7_HWCR:
-- 
2.40.0.rc2.332.ga46443480c-goog