Re: [PATCH v3] ARM64: Dynamically allocate cpumasks and increase supported CPUs to 512

[Christoph Lameter (Ampere)]

On Mon, 11 Mar 2024, Christoph Lameter (Ampere) wrote:

> This could be an issue in the ARM64 arch code itself where there maybe an 
> assumption elsewhere that a cpumask can always store up to NR_CPU cpus and 
> not only nr_cpu_ids as OFFSTACK does.
>
> How can I exercise the opp driver in order to recreate the problem?
>
> I assume the opp driver is ARM specific? x86 defaults to OFFSTACK so if there 
> is an issue with OFFSTACK in opp then it should fail with kernel default 
> configuration on that platform.

I checked the ARM64 arch sources use of NR_CPUS and its all fine.

Also verified in my testing logs that CONFIG_PM_OPP was set in all tests.

No warnings in the kernel log during those tests.

How to reproduce this?