Re: [PATCH RFC] x86/kvm: expose the CPUID of SPEC_CTRL and STIBP to guests

[Wei Wang <wei.w.wang@intel.com>]

On 01/09/2018 04:39 PM, Paolo Bonzini wrote:
> On 09/01/2018 07:25, Wei Wang wrote:
>> This patch shows an alternative approach to the one posted here:
>> https://www.mail-archive.com/linux-kernel@vger.kernel.org/msg1580364.html
>>
>> The advantages are
>> 1) Simpler;
>> 2) More reasonable because this is used to fill the hardware security
>> hole, for all the x86 cpus that physically support the two CPUIDs,
>> which means the hole already exists physically. All the VMs should
>> use this feature no matter what CPU model they are using. So, exposing
>> the two CPUIDs as long as they are physically supported by the hardware,
>> and this doesn't require the QEMU side hardcode as usual.
>>
>> When the related feature bits are added to the kernel, and we can simply
>> change it to:
>> 	best->edx |= F(SPEC_CTRL) | F(PRED_CMD);
> Is this meant to replace the whole series or just patch 1/7?  The
> functions in patch 1/7 are used later by vmx.c and svm.c.
>

The pointer should have pointed to 7/7 (not 1/7). Just patch 7/7 actually.

Best,
Wei