[PATCH v2 2/4] Add parameter to control A/D bits support

From: Xudong Hao
Date: Sun May 20 2012 - 23:50:57 EST


Add kernel parameter to control A/D bits support, it's on by default.

Signed-off-by: Haitao Shan <haitao.shan@xxxxxxxxx>
Signed-off-by: Xudong Hao <xudong.hao@xxxxxxxxx>
---
arch/x86/kvm/vmx.c | 12 ++++++++++++
1 files changed, 12 insertions(+), 0 deletions(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 3062ea9..f3858bf 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -71,6 +71,9 @@ static bool __read_mostly enable_unrestricted_guest = 1;
module_param_named(unrestricted_guest,
enable_unrestricted_guest, bool, S_IRUGO);

+static bool __read_mostly enable_ept_ad_bits = 1;
+module_param_named(eptad, enable_ept_ad_bits, bool, S_IRUGO);
+
static bool __read_mostly emulate_invalid_guest_state = 0;
module_param(emulate_invalid_guest_state, bool, S_IRUGO);

@@ -786,6 +789,11 @@ static inline bool cpu_has_vmx_ept_4levels(void)
return vmx_capability.ept & VMX_EPT_PAGE_WALK_4_BIT;
}

+static inline bool cpu_has_vmx_ept_ad_bits(void)
+{
+ return vmx_capability.ept & VMX_EPT_AD_BIT;
+}
+
static inline bool cpu_has_vmx_invept_individual_addr(void)
{
return vmx_capability.ept & VMX_EPT_EXTENT_INDIVIDUAL_BIT;
@@ -2624,8 +2632,12 @@ static __init int hardware_setup(void)
!cpu_has_vmx_ept_4levels()) {
enable_ept = 0;
enable_unrestricted_guest = 0;
+ enable_ept_ad_bits = 0;
}

+ if (!cpu_has_vmx_ept_ad_bits())
+ enable_ept_ad_bits = 0;
+
if (!cpu_has_vmx_unrestricted_guest())
enable_unrestricted_guest = 0;

--
1.5.6

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