Re: [PATCH v4 2/3] KVM: nVMX: Validate the IA32_BNDCFGS on nested VM-entry

From: Wanpeng Li
Date: Sun Nov 05 2017 - 20:32:19 EST


2017-11-04 1:52 GMT+08:00 Jim Mattson <jmattson@xxxxxxxxxx>:
> On Thu, Nov 2, 2017 at 5:35 PM, Wanpeng Li <kernellwp@xxxxxxxxx> wrote:
>> From: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>>
>> According to the SDM, if the "load IA32_BNDCFGS" VM-entry controls is 1, the
>> following checks are performed on the field for the IA32_BNDCFGS MSR:
>> - Bits reserved in the IA32_BNDCFGS MSR must be 0.
>> - The linear address in bits 63:12 must be canonical.
>>
>> Reviewed-by: Konrad Rzeszutek Wilk <konrad.wilk@xxxxxxxxxx>
>> Cc: Paolo Bonzini <pbonzini@xxxxxxxxxx>
>> Cc: Radim KrÄmÃÅ <rkrcmar@xxxxxxxxxx>
>> Cc: Jim Mattson <jmattson@xxxxxxxxxx>
>> Signed-off-by: Wanpeng Li <wanpeng.li@xxxxxxxxxxx>
>> ---
>> v3 -> v4:
>> * simply condition
>> * use && instead of nested "if"s
>>
>> arch/x86/kvm/vmx.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/arch/x86/kvm/vmx.c b/arch/x86/kvm/vmx.c
>> index e6c8ffa..6cf3972 100644
>> --- a/arch/x86/kvm/vmx.c
>> +++ b/arch/x86/kvm/vmx.c
>> @@ -10805,6 +10805,11 @@ static int check_vmentry_postreqs(struct kvm_vcpu *vcpu, struct vmcs12 *vmcs12,
>> return 1;
>> }
>>
>> + if (kvm_mpx_supported() &&
>
> I think you kept the wrong conjunct from the previous version. Drop
> kvm_mpx_supported() and restore the test for
> (vmcs12->vm_entry_controls & VM_ENTRY_LOAD_BNDCFGS).

Yeah, I misunderstand the English.

Regards,
Wanpeng Li