linux-kernel - [PATCH 08/15] KVM: SVM: Remove useless check in svm_load_mmu

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Date:   Mon,  8 Nov 2021 20:44:00 +0800
From:   Lai Jiangshan <jiangshanlai@...il.com>
To:     linux-kernel@...r.kernel.org, kvm@...r.kernel.org,
        Paolo Bonzini <pbonzini@...hat.com>
Cc:     Lai Jiangshan <laijs@...ux.alibaba.com>,
        Sean Christopherson <seanjc@...gle.com>,
        Vitaly Kuznetsov <vkuznets@...hat.com>,
        Wanpeng Li <wanpengli@...cent.com>,
        Jim Mattson <jmattson@...gle.com>,
        Joerg Roedel <joro@...tes.org>,
        Thomas Gleixner <tglx@...utronix.de>,
        Ingo Molnar <mingo@...hat.com>, Borislav Petkov <bp@...en8.de>,
        x86@...nel.org, "H. Peter Anvin" <hpa@...or.com>
Subject: [PATCH 08/15] KVM: SVM: Remove useless check in svm_load_mmu_pgd()

From: Lai Jiangshan <laijs@...ux.alibaba.com>

VCPU_EXREG_CR3 is never cleared from vcpu->arch.regs_avail in SVM so
the if-branch is always false and useless, just remove it.

Signed-off-by: Lai Jiangshan <laijs@...ux.alibaba.com>
---
 arch/x86/kvm/svm/svm.c | 2 --
 1 file changed, 2 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index e3607fa025d3..b7da66935e72 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -4000,8 +4000,6 @@ static void svm_load_mmu_pgd(struct kvm_vcpu *vcpu, hpa_t root_hpa,
 
 		hv_track_root_tdp(vcpu, root_hpa);
 
-		if (!test_bit(VCPU_EXREG_CR3, (ulong *)&vcpu->arch.regs_avail))
-			return;
 		cr3 = vcpu->arch.cr3;
 	} else if (vcpu->arch.mmu->shadow_root_level >= PT64_ROOT_4LEVEL) {
 		cr3 = __sme_set(root_hpa) | kvm_get_active_pcid(vcpu);
-- 
2.19.1.6.gb485710b