linux-kernel - [PATCH] KVM: x86: Fix the initial value of mcg

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Date:   Thu, 20 Oct 2022 11:16:15 +0800
From:   Xiaoyao Li <xiaoyao.li@...el.com>
To:     Sean Christopherson <seanjc@...gle.com>,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     kvm@...r.kernel.org, linux-kernel@...r.kernel.org,
        Xiaoyao Li <xiaoyao.li@...el.com>
Subject: [PATCH] KVM: x86: Fix the initial value of mcg_cap

vcpu->arch.mcg_cap represents the value of MSR_IA32_MCG_CAP. It's
set via ioctl(KVM_X86_SETUP_MCE) from userspace when exposing and
configuring MCE to guest.

It's wrong to leave the default value as KVM_MAX_MCE_BANKS.

Signed-off-by: Xiaoyao Li <xiaoyao.li@...el.com>
---
 arch/x86/kvm/x86.c | 1 -
 1 file changed, 1 deletion(-)

diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c
index 4bd5f8a751de..ca8f4a3e698d 100644
--- a/arch/x86/kvm/x86.c
+++ b/arch/x86/kvm/x86.c
@@ -11801,7 +11801,6 @@ int kvm_arch_vcpu_create(struct kvm_vcpu *vcpu)
 					    GFP_KERNEL_ACCOUNT);
 	if (!vcpu->arch.mce_banks || !vcpu->arch.mci_ctl2_banks)
 		goto fail_free_mce_banks;
-	vcpu->arch.mcg_cap = KVM_MAX_MCE_BANKS;
 
 	if (!zalloc_cpumask_var(&vcpu->arch.wbinvd_dirty_mask,
 				GFP_KERNEL_ACCOUNT))
-- 
2.27.0