Re: [PATCH 06/20] x86/msr: Standardize on 'u32' MSR indices in

H. Peter Anvin
2025-04-10T06:19:14Z

On 4/9/25 20:53, Xin Li wrote:
> On 4/9/2025 8:29 PM, H. Peter Anvin wrote:
>> On April 9, 2025 8:18:12 PM PDT, Xin Li <xin@zytor.com> wrote:
>>> A question NOT related to this patch set, the MSR write API prototype
>>> defined in struct pv_cpu_ops as:
>>>     void (*write_msr)(unsigned int msr, unsigned low, unsigned high);
>>>
>>> Will it be better to add "const" to its arguments?  I.e.,
>>>     void (*write_msr)(const u32 msr, const u32 low, const u32 high);
>>>
>>
>> No, that makes no sense (it would have absolutely no effect.)
>>
>
> For the API definition, yes, it has no effect.
>
> While it makes the API definition more explicit, and its implementations
> for native and Xen would be:
>
> void {native,xen}_write_msr(const u32 msr, const u32 low, const u32 high)
> {
>     ....
> }
>
> not worth it at all?
>

No, and as you know, I'd like to get rid of the native_ and xen_
functions entirely anyway.

-hpa