linux-kernel - [PATCH 10/31] KVM: SVM: do not intercept task switch with NPT

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Message-Id: <1208773797-7829-11-git-send-email-avi@qumranet.com>
Date:	Mon, 21 Apr 2008 13:29:36 +0300
From:	Avi Kivity <avi@...ranet.com>
To:	kvm-devel@...ts.sourceforge.net
Cc:	linux-kernel@...r.kernel.org, Joerg Roedel <joerg.roedel@....com>
Subject: [PATCH 10/31] KVM: SVM: do not intercept task switch with NPT

From: Joerg Roedel <joerg.roedel@....com>

When KVM uses NPT there is no reason to intercept task switches. This patch
removes the intercept for it in that case.

Signed-off-by: Joerg Roedel <joerg.roedel@....com>
Signed-off-by: Avi Kivity <avi@...ranet.com>
---
 arch/x86/kvm/svm.c |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index da3ddef..8d04aed 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -591,6 +591,7 @@ static void init_vmcb(struct vcpu_svm *svm)
 	if (npt_enabled) {
 		/* Setup VMCB for Nested Paging */
 		control->nested_ctl = 1;
+		control->intercept &= ~(1ULL << INTERCEPT_TASK_SWITCH);
 		control->intercept_exceptions &= ~(1 << PF_VECTOR);
 		control->intercept_cr_read &= ~(INTERCEPT_CR0_MASK|
 						INTERCEPT_CR3_MASK);
-- 
1.5.5

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