linux-kernel - [PATCH v2 20/46] KVM: SVM: Don't bother writing vmcb->save.rip at vCPU RESET/INIT

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Message-Id: <20210713163324.627647-21-seanjc@google.com>
Date:   Tue, 13 Jul 2021 09:32:58 -0700
From:   Sean Christopherson <seanjc@...gle.com>
To:     Paolo Bonzini <pbonzini@...hat.com>
Cc:     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>, kvm@...r.kernel.org,
        linux-kernel@...r.kernel.org, Reiji Watanabe <reijiw@...gle.com>
Subject: [PATCH v2 20/46] KVM: SVM: Don't bother writing vmcb->save.rip at
 vCPU RESET/INIT

Drop unnecessary initialization of vmcb->save.rip during vCPU RESET/INIT,
as svm_vcpu_run() unconditionally propagates VCPU_REGS_RIP to save.rip.

No true functional change intended.

Reviewed-by: Reiji Watanabe <reijiw@...gle.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/svm/svm.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index 268580713938..0101646e42e0 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1266,8 +1266,7 @@ static void init_vmcb(struct kvm_vcpu *vcpu)
 	svm_set_efer(vcpu, 0);
 	save->dr6 = 0xffff0ff0;
 	kvm_set_rflags(vcpu, X86_EFLAGS_FIXED);
-	save->rip = 0x0000fff0;
-	vcpu->arch.regs[VCPU_REGS_RIP] = save->rip;
+	vcpu->arch.regs[VCPU_REGS_RIP] = 0x0000fff0;
 
 	/*
 	 * svm_set_cr0() sets PG and WP and clears NW and CD on save->cr0.
-- 
2.32.0.93.g670b81a890-goog