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[213.175.37.10]) by smtp.gmail.com with ESMTPSA id f207sm1188765wme.9.2020.02.17.08.16.35 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 17 Feb 2020 08:16:35 -0800 (PST) From: Vitaly Kuznetsov To: linmiaohe Cc: kvm@vger.kernel.org, linux-kernel@vger.kernel.org, x86@kernel.org, pbonzini@redhat.com, rkrcmar@redhat.com, sean.j.christopherson@intel.com, wanpengli@tencent.com, jmattson@google.com, joro@8bytes.org, tglx@linutronix.de, mingo@redhat.com, bp@alien8.de, hpa@zytor.com Subject: Re: [PATCH] KVM: x86: eliminate some unreachable code In-Reply-To: <1581562405-30321-1-git-send-email-linmiaohe@huawei.com> References: <1581562405-30321-1-git-send-email-linmiaohe@huawei.com> Date: Mon, 17 Feb 2020 17:16:34 +0100 Message-ID: <87k14l9okd.fsf@vitty.brq.redhat.com> MIME-Version: 1.0 Content-Type: text/plain Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org linmiaohe writes: > From: Miaohe Lin > > These code are unreachable, remove them. > > Signed-off-by: Miaohe Lin > --- > arch/x86/kvm/vmx/vmx.c | 1 - > arch/x86/kvm/x86.c | 3 --- > 2 files changed, 4 deletions(-) > > diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c > index bb5c33440af8..b6d4eafe01cf 100644 > --- a/arch/x86/kvm/vmx/vmx.c > +++ b/arch/x86/kvm/vmx/vmx.c > @@ -4505,7 +4505,6 @@ static bool rmode_exception(struct kvm_vcpu *vcpu, int vec) > case GP_VECTOR: > case MF_VECTOR: > return true; > - break; > } > return false; > } Unrelated to your change but what I don't in rmode_exception() is the second "/* fall through */" instead of just 'return true;', it makes it harder to read. > diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c > index fbabb2f06273..a597009aefd7 100644 > --- a/arch/x86/kvm/x86.c > +++ b/arch/x86/kvm/x86.c > @@ -3081,7 +3081,6 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > break; > case APIC_BASE_MSR ... APIC_BASE_MSR + 0x3ff: > return kvm_x2apic_msr_read(vcpu, msr_info->index, &msr_info->data); > - break; > case MSR_IA32_TSCDEADLINE: > msr_info->data = kvm_get_lapic_tscdeadline_msr(vcpu); > break; > @@ -3164,7 +3163,6 @@ int kvm_get_msr_common(struct kvm_vcpu *vcpu, struct msr_data *msr_info) > return kvm_hv_get_msr_common(vcpu, > msr_info->index, &msr_info->data, > msr_info->host_initiated); > - break; > case MSR_IA32_BBL_CR_CTL3: > /* This legacy MSR exists but isn't fully documented in current > * silicon. It is however accessed by winxp in very narrow > @@ -8471,7 +8469,6 @@ static inline int vcpu_block(struct kvm *kvm, struct kvm_vcpu *vcpu) > break; > default: > return -EINTR; > - break; > } > return 1; > } Reviewed-by: Vitaly Kuznetsov -- Vitaly