linux-kernel - [PATCH] x86: Make x2APIC support depend on interrupt remapping or guest support

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Date:	Sat, 05 Jul 2014 09:47:54 +0200
From:	Jan Kiszka <jan.kiszka@....de>
To:	Thomas Gleixner <tglx@...utronix.de>,
	Ingo Molnar <mingo@...hat.com>,
	"H. Peter Anvin" <hpa@...or.com>, x86 <x86@...nel.org>,
	Linux Kernel Mailing List <linux-kernel@...r.kernel.org>
CC:	kvm <kvm@...r.kernel.org>
Subject: [PATCH] x86: Make x2APIC support depend on interrupt remapping or
 guest support

From: Jan Kiszka <jan.kiszka@...mens.com>

We are able to use x2APIC mode in the absence of interrupt remapping on
certain hypervisors. So it if fine to disable IRQ_REMAP without having
to give up x2APIC support.

Signed-off-by: Jan Kiszka <jan.kiszka@...mens.com>
---
 arch/x86/Kconfig | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index a8f749e..30a9987 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -310,7 +310,7 @@ config SMP
 
 config X86_X2APIC
 	bool "Support x2apic"
-	depends on X86_LOCAL_APIC && X86_64 && IRQ_REMAP
+	depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
 	---help---
 	  This enables x2apic support on CPUs that have this feature.
 



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