linux-kernel - [PATCH v2 18/46] KVM: x86: Consolidate APIC base RESET initialization code

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20210713163324.627647-19-seanjc@google.com>
Date:   Tue, 13 Jul 2021 09:32:56 -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 18/46] KVM: x86: Consolidate APIC base RESET initialization code

Consolidate the APIC base RESET logic, which is currently spread out
across both x86 and vendor code.  For an in-kernel APIC, the vendor code
is redundant.  But for a userspace APIC, KVM relies on the vendor code
to initialize vcpu->arch.apic_base.  Hoist the vcpu->arch.apic_base
initialization above the !apic check so that it applies to both flavors
of APIC emulation, and delete the vendor code.

Reviewed-by: Reiji Watanabe <reijiw@...gle.com>
Signed-off-by: Sean Christopherson <seanjc@...gle.com>
---
 arch/x86/kvm/lapic.c   | 14 ++++++++------
 arch/x86/kvm/svm/svm.c |  6 ------
 arch/x86/kvm/vmx/vmx.c |  7 -------
 3 files changed, 8 insertions(+), 19 deletions(-)

diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 295a9d02a9a5..76fb00921203 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -2323,18 +2323,20 @@ void kvm_lapic_reset(struct kvm_vcpu *vcpu, bool init_event)
 	struct kvm_lapic *apic = vcpu->arch.apic;
 	int i;
 
-	if (!apic)
-		return;
-
-	/* Stop the timer in case it's a reset to an active apic */
-	hrtimer_cancel(&apic->lapic_timer.timer);
-
 	if (!init_event) {
 		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
 				       MSR_IA32_APICBASE_ENABLE;
 		if (kvm_vcpu_is_reset_bsp(vcpu))
 			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
+	}
 
+	if (!apic)
+		return;
+
+	/* Stop the timer in case it's a reset to an active apic */
+	hrtimer_cancel(&apic->lapic_timer.timer);
+
+	if (!init_event) {
 		apic->base_address = APIC_DEFAULT_PHYS_BASE;
 
 		kvm_apic_set_xapic_id(apic, vcpu->vcpu_id);
diff --git a/arch/x86/kvm/svm/svm.c b/arch/x86/kvm/svm/svm.c
index cef9520fe77f..f7486b1645de 100644
--- a/arch/x86/kvm/svm/svm.c
+++ b/arch/x86/kvm/svm/svm.c
@@ -1349,12 +1349,6 @@ static void svm_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	svm->spec_ctrl = 0;
 	svm->virt_spec_ctrl = 0;
 
-	if (!init_event) {
-		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
-				       MSR_IA32_APICBASE_ENABLE;
-		if (kvm_vcpu_is_reset_bsp(vcpu))
-			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
-	}
 	init_vmcb(vcpu);
 
 	/*
diff --git a/arch/x86/kvm/vmx/vmx.c b/arch/x86/kvm/vmx/vmx.c
index e6cc389ec697..ff82c05b948b 100644
--- a/arch/x86/kvm/vmx/vmx.c
+++ b/arch/x86/kvm/vmx/vmx.c
@@ -4406,13 +4406,6 @@ static void vmx_vcpu_reset(struct kvm_vcpu *vcpu, bool init_event)
 	vmx->hv_deadline_tsc = -1;
 	kvm_set_cr8(vcpu, 0);
 
-	if (!init_event) {
-		vcpu->arch.apic_base = APIC_DEFAULT_PHYS_BASE |
-				       MSR_IA32_APICBASE_ENABLE;
-		if (kvm_vcpu_is_reset_bsp(vcpu))
-			vcpu->arch.apic_base |= MSR_IA32_APICBASE_BSP;
-	}
-
 	vmx_segment_cache_clear(vmx);
 
 	seg_setup(VCPU_SREG_CS);
-- 
2.32.0.93.g670b81a890-goog