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Subject[PATCH 1/2] KVM: VMX: Don't expose unrestricted_guest is enabled if ept is disabled
From: Wanpeng Li <>

SDM mentioned:

"If either the “unrestricted guest” VM-execution control or the “mode-based
execute control for EPT” VM- execution control is 1, the “enable EPT”
VM-execution control must also be 1."

However, we can still observe unrestricted_guest is Y after inserting the kvm-intel.ko
w/ ept=N. It depends on later starts a guest in order that the function
vmx_compute_secondary_exec_control() can be executed, then both the module parameter
and exec control fields will be amended.

This patch fixes it by amending module parameter immediately during vmcs data setup.

Cc: Paolo Bonzini <>
Cc: Radim Krčmář <>
Signed-off-by: Wanpeng Li <>
arch/x86/kvm/vmx.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
index 244e366..3e664ca 100644
--- a/arch/x86/kvm/vmx.c
+++ b/arch/x86/kvm/vmx.c
@@ -6737,7 +6737,7 @@ static __init int hardware_setup(void)
if (!cpu_has_vmx_ept_ad_bits() || !enable_ept)
enable_ept_ad_bits = 0;

- if (!cpu_has_vmx_unrestricted_guest())
+ if (!cpu_has_vmx_unrestricted_guest() || !enable_ept)
enable_unrestricted_guest = 0;

if (!cpu_has_vmx_flexpriority())
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