From: Jim Mattson <jmattson@google.com>
Date: Fri, 29 Sep 2023 23:02:44 +0000 (-0700)
Subject: KVM: x86: Allow HWCR.McStatusWrEn to be cleared once set
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=598a790fc20f06e5582c939a4c5864ff1105c477;p=linux.git

KVM: x86: Allow HWCR.McStatusWrEn to be cleared once set

When HWCR is set to 0, store 0 in vcpu->arch.msr_hwcr.

Fixes: 191c8137a939 ("x86/kvm: Implement HWCR support")
Signed-off-by: Jim Mattson <jmattson@google.com>
Link: https://lore.kernel.org/r/20230929230246.1954854-2-jmattson@google.com
Signed-off-by: Sean Christopherson <seanjc@google.com>
---

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 42b33ef997a5d..6f4534046803a 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -3791,12 +3791,11 @@ int kvm_set_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info)
 		data &= ~(u64)0x8;	/* ignore TLB cache disable */
 
 		/* Handle McStatusWrEn */
-		if (data == BIT_ULL(18)) {
-			vcpu->arch.msr_hwcr = data;
-		} else if (data != 0) {
+		if (data & ~BIT_ULL(18)) {
 			kvm_pr_unimpl_wrmsr(vcpu, msr, data);
 			return 1;
 		}
+		vcpu->arch.msr_hwcr = data;
 		break;
 	case MSR_FAM10H_MMIO_CONF_BASE:
 		if (data != 0) {