linux-kernel - [PATCH v3 08/14] KVM: VMX: optimize APIC ID read with APICv

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Message-Id: <20160712200930.32143-9-rkrcmar@redhat.com>
Date:	Tue, 12 Jul 2016 22:09:24 +0200
From:	Radim Krčmář <rkrcmar@...hat.com>
To:	linux-kernel@...r.kernel.org, kvm@...r.kernel.org
Cc:	Paolo Bonzini <pbonzini@...hat.com>,
	"Lan, Tianyu" <tianyu.lan@...el.com>,
	Igor Mammedov <imammedo@...hat.com>,
	Jan Kiszka <jan.kiszka@....de>, Peter Xu <peterx@...hat.com>,
	Yang Zhang <yang.zhang.wz@...il.com>
Subject: [PATCH v3 08/14] KVM: VMX: optimize APIC ID read with APICv

The register is in hardware-compatible format now, so there is not need
to intercept.

Reviewed-by: Paolo Bonzini <pbonzini@...hat.com>
Signed-off-by: Radim Krčmář <rkrcmar@...hat.com>
---
 arch/x86/kvm/vmx.c | 3 ---
 1 file changed, 3 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index e51503063181..24b505fda7ad 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6456,9 +6456,6 @@ static __init int hardware_setup(void)
 	for (msr = 0x800; msr <= 0x8ff; msr++)
 		vmx_disable_intercept_msr_read_x2apic(msr);
 
-	/* According SDM, in x2apic mode, the whole id reg is used.  But in
-	 * KVM, it only use the highest eight bits. Need to intercept it */
-	vmx_enable_intercept_msr_read_x2apic(0x802);
 	/* TMCCT */
 	vmx_enable_intercept_msr_read_x2apic(0x839);
 	/* TPR */
-- 
2.9.0