linux-kernel - [PATCH 6/7] KVM: SVM: Rework hflags handling

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Date:	Wed, 13 Jul 2011 17:32:24 +0200
From:	Joerg Roedel <joerg.roedel@....com>
To:	Avi Kivity <avi@...hat.com>, Marcelo Tosatti <mtosatti@...hat.com>
CC:	<kvm@...r.kernel.org>, <linux-kernel@...r.kernel.org>,
	Joerg Roedel <joro@...tes.org>
Subject: [PATCH 6/7] KVM: SVM: Rework hflags handling

From: Joerg Roedel <joro@...tes.org>

This patch moves the unsetting of the hflags used for
nesting into the #vmexit path instead of doing everything in
the vmrun path.

Signed-off-by: Joerg Roedel <joro@...tes.org>
---
 arch/x86/kvm/svm.c |   17 ++++++++---------
 1 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c
index f2cca2c..c83315a 100644
--- a/arch/x86/kvm/svm.c
+++ b/arch/x86/kvm/svm.c
@@ -2256,6 +2256,8 @@ static int nested_svm_vmexit(struct vcpu_svm *svm)
 
 	mark_all_dirty(svm->vmcb);
 
+	svm->vcpu.arch.hflags &=  ~(HF_VINTR_MASK | HF_HIF_MASK);
+
 	nested_svm_unmap(page);
 
 	nested_svm_uninit_mmu_context(&svm->vcpu);
@@ -2317,6 +2319,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	struct vmcb *nested_vmcb;
 	struct page *page;
 	u64 vmcb_gpa;
+	u64 rflags;
 
 	vmcb_gpa = svm->vmcb->save.rax;
 
@@ -2350,6 +2353,8 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	kvm_clear_exception_queue(&svm->vcpu);
 	kvm_clear_interrupt_queue(&svm->vcpu);
 
+	rflags = kvm_get_rflags(&svm->vcpu);
+
 	/*
 	 * Save the old vmcb, so we don't need to pick what we save, but can
 	 * restore everything when a VMEXIT occurs
@@ -2357,7 +2362,7 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	svm->host_vmcb->save.efer   = svm->vcpu.arch.efer;
 	svm->host_vmcb->save.cr0    = kvm_read_cr0(&svm->vcpu);
 	svm->host_vmcb->save.cr4    = svm->vcpu.arch.cr4;
-	svm->host_vmcb->save.rflags = kvm_get_rflags(&svm->vcpu);
+	svm->host_vmcb->save.rflags = rflags;
 	svm->host_vmcb->save.rax    = svm->vcpu.arch.regs[VCPU_REGS_RAX];
 	svm->host_vmcb->save.rsp    = svm->vcpu.arch.regs[VCPU_REGS_RSP];
 	svm->host_vmcb->save.rip    = svm->vcpu.arch.regs[VCPU_REGS_RIP];
@@ -2365,17 +2370,11 @@ static bool nested_svm_vmrun(struct vcpu_svm *svm)
 	if (!npt_enabled)
 		svm->host_vmcb->save.cr3 = kvm_read_cr3(&svm->vcpu);
 
-	if (kvm_get_rflags(&svm->vcpu) & X86_EFLAGS_IF)
-		svm->vcpu.arch.hflags |= HF_HIF_MASK;
-	else
-		svm->vcpu.arch.hflags &= ~HF_HIF_MASK;
+	svm->vcpu.arch.hflags |= rflags & X86_EFLAGS_IF ? HF_HIF_MASK   : 0;
 
-	if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK)
+	if (nested_vmcb->control.int_ctl & V_INTR_MASKING_MASK) {
 		svm->vcpu.arch.hflags |= HF_VINTR_MASK;
-	else
-		svm->vcpu.arch.hflags &= ~HF_VINTR_MASK;
 
-	if (svm->vcpu.arch.hflags & HF_VINTR_MASK) {
 		/* We only want the cr8 intercept bits of the guest */
 		clr_cr_intercept(svm, INTERCEPT_CR8_READ);
 		clr_cr_intercept(svm, INTERCEPT_CR8_WRITE);
-- 
1.7.4.1


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