linux-kernel - [PATCH] svm: Do not support AVIC if not CONFIG_X86_LOCAL

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Date:	Wed, 15 Jun 2016 17:24:36 -0500
From:	Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>
To:	<linux-kernel@...r.kernel.org>, <kvm@...r.kernel.org>,
	<pbonzini@...hat.com>
CC:	<rkrcmar@...hat.com>, <fengguang.wu@...el.com>,
	<kbuild-all@...org>,
	Suravee Suthikulpanit <Suravee.Suthikulpanit@....com>,
	Suravee Suthikulpanit <suravee.suthikulpanit@....com>
Subject: [PATCH] svm: Do not support AVIC if not CONFIG_X86_LOCAL_APIC

Add logic to disable AVIC #ifndef CONFIG_X86_LOCAL_APIC.

Suggested-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@....com>
---
 arch/x86/kvm/svm.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index 0d2aa13..1b18b50 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -241,7 +241,9 @@ module_param(nested, int, S_IRUGO);
 
 /* enable / disable AVIC */
 static int avic;
+#ifdef CONFIG_X86_LOCAL_APIC
 module_param(avic, int, S_IRUGO);
+#endif
 
 static void svm_set_cr0(struct kvm_vcpu *vcpu, unsigned long cr0);
 static void svm_flush_tlb(struct kvm_vcpu *vcpu);
@@ -1023,7 +1025,10 @@ static __init int svm_hardware_setup(void)
 	} else
 		kvm_disable_tdp();
 
-	if (avic && (!npt_enabled || !boot_cpu_has(X86_FEATURE_AVIC)))
+	if (avic)
+		if (!npt_enabled ||
+		    !boot_cpu_has(X86_FEATURE_AVIC) ||
+		    !IS_ENABLED(CONFIG_X86_LOCAL_APIC))
 		avic = false;
 
 	if (avic) {
-- 
1.9.1