Re: [PATCH 2/6] x86/sev: add support for enabling RMPOPT

[Kalra, Ashish]

On 2/18/2026 11:01 AM, Dave Hansen wrote:
> On 2/18/26 08:55, Kalra, Ashish wrote:
>> Because, setting RMPOPT_BASE MSR (which is a per-core MSR) and
>> RMPOPT instruction need to be issued on only one thread per core. If
>> the primary thread is offlined and secondary thread is not
>> considered, we will miss/skip setting either the RMPOPT_BASE MSR or
>> not issuing the RMPOPT instruction for that physical CPU, which
>> means no RMP optimizations enabled for that physical CPU.
> What is the harm of issuing it twice per core?

Why to issue it if we can avoid it.

It is not that complex to setup a cpumask containing the online primary
or secondary thread and then issue the RMPOPT instruction only once per
thread.

Thanks,
Ashish