[PATCH] kvm: reduce couple for ACC_EXEC_MASK

[Lai Jiangshan]

The statement "access &= ~(gpte >> PT64_NX_SHIFT);" tries
to clear bit ACC_EXEC_MASK actually. This statement
relies PT64_NX_SHIFT==63&&ACC_EXEC_MASK=1

This patch reduces this couple.


Signed-off-by: Lai Jiangshan <laijs@xxxxxxxxxxxxxx>
---
diff --git a/arch/x86/kvm/paging_tmpl.h b/arch/x86/kvm/paging_tmpl.h
index 81eab9a..34f4aa2 100644
--- a/arch/x86/kvm/paging_tmpl.h
+++ b/arch/x86/kvm/paging_tmpl.h
@@ -101,11 +101,9 @@ static unsigned FNAME(gpte_access)(struct kvm_vcpu *vcpu, pt_element_t gpte)
 {
 	unsigned access;
 
-	access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK)) | ACC_EXEC_MASK;
-#if PTTYPE == 64
-	if (is_nx(vcpu))
-		access &= ~(gpte >> PT64_NX_SHIFT);
-#endif
+	access = (gpte & (PT_WRITABLE_MASK | PT_USER_MASK));
+	if (PTTYPE != 64 || !is_nx(vcpu) || (gpte & PT64_NX_MASK))
+		access |= ACC_EXEC_MASK;
 	return access;
 }
 
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/