Re: [PATCH v12 00/16] AMD broadcast TLB invalidation

[Borislav Petkov]

On Sat, Feb 22, 2025 at 11:05:41AM -0500, Rik van Riel wrote:
> It's crashing when writing the value to the
> invlpgb_count_max variable.
> 
> This would be because:
> 1) invlpgb_count_max is marked __ro_after_init, making
>    it read-only after the system has finished booting, but
> 2) get_cpu_cap gets run at resume and CPU hotplug time!

Yet another side effect of us reading CPUID gazillion times. /facepalm.

> Borislav, do you prefer I move the initialization of 
> invlpgb_count_max back to where it was before, or get
> rid of the __ro_after_init thing?

You probably could move it back to where it was - cpu_detect_tlb_amd - and
leave it __ro_after_init because cpu_detect_tlb() is run on the BSP only so
I'm guessing resume doesn't bootstrap that thing...

Thx.

-- 
Regards/Gruss,
    Boris.

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