linux-kernel - [PATCH 1/5] mmu: mark spte present if the x bit is set

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Message-Id: <1467088360-10186-2-git-send-email-bsd@redhat.com>
Date:	Tue, 28 Jun 2016 00:32:36 -0400
From:	Bandan Das <bsd@...hat.com>
To:	kvm@...r.kernel.org
Cc:	pbonzini@...hat.com, guangrong.xiao@...ux.intel.com,
	linux-kernel@...r.kernel.org
Subject: [PATCH 1/5] mmu: mark spte present if the x bit is set

This is safe because is_shadow_present_pte() is called
on host controlled page table and we know the spte is
valid

Signed-off-by: Bandan Das <bsd@...hat.com>
---
 arch/x86/kvm/mmu.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c
index def97b3..a50af79 100644
--- a/arch/x86/kvm/mmu.c
+++ b/arch/x86/kvm/mmu.c
@@ -304,7 +304,8 @@ static int is_nx(struct kvm_vcpu *vcpu)
 
 static int is_shadow_present_pte(u64 pte)
 {
-	return pte & PT_PRESENT_MASK && !is_mmio_spte(pte);
+	return pte & (PT_PRESENT_MASK | shadow_x_mask) &&
+		!is_mmio_spte(pte);
 }
 
 static int is_large_pte(u64 pte)
-- 
2.5.5