Re: [PATCH] KVM: nVMX: Disable unrestricted mode if ept=0

From: Paolo Bonzini
Date: Wed Dec 10 2014 - 07:07:04 EST




On 06/12/2014 16:02, Bandan Das wrote:
>
> If L0 has disabled EPT, don't advertise unrestricted
> mode at all since it depends on EPT to run real mode code.
>
> Signed-off-by: Bandan Das <bsd@xxxxxxxxxx>
> ---
> arch/x86/kvm/vmx.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
> index 3e556c6..ed70394 100644
> --- a/arch/x86/kvm/vmx.c
> +++ b/arch/x86/kvm/vmx.c
> @@ -2377,12 +2377,12 @@ static __init void nested_vmx_setup_ctls_msrs(void)
> nested_vmx_secondary_ctls_low = 0;
> nested_vmx_secondary_ctls_high &=
> SECONDARY_EXEC_VIRTUALIZE_APIC_ACCESSES |
> - SECONDARY_EXEC_UNRESTRICTED_GUEST |
> SECONDARY_EXEC_WBINVD_EXITING;
>
> if (enable_ept) {
> /* nested EPT: emulate EPT also to L1 */
> - nested_vmx_secondary_ctls_high |= SECONDARY_EXEC_ENABLE_EPT;
> + nested_vmx_secondary_ctls_high |= SECONDARY_EXEC_ENABLE_EPT |
> + SECONDARY_EXEC_UNRESTRICTED_GUEST;
> nested_vmx_ept_caps = VMX_EPT_PAGE_WALK_4_BIT |
> VMX_EPTP_WB_BIT | VMX_EPT_2MB_PAGE_BIT |
> VMX_EPT_INVEPT_BIT;
>

Thanks, applied with

Fixes: 92fbc7b195b824e201d9f06f2b93105f72384d65
Cc: stable@xxxxxxxxxxxxxxx

Paolo
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