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Date: Wed, 12 Jun 2024 10:07:44 -0700 (PDT)
From: "Christoph Lameter (Ampere)" <cl@gentwo.org>
To: Peter Zijlstra <peterz@infradead.org>
cc: Thomas Gleixner <tglx@linutronix.de>, axboe@kernel.dk, 
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    malteskarupke@web.de
Subject: Re: [PATCH v1 11/14] futex: Implement FUTEX2_NUMA
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On Mon, 31 Jul 2023, Peter Zijlstra wrote:

>> Is nr_node_ids guaranteed to be stable after init? It's marked
>> __read_mostly, but not __ro_after_init.
>
> AFAICT it is only ever written to in setup_nr_node_ids() and that is all
> __init code. So I'm thinking this could/should indeed be
> __ro_after_init. Esp. so since it is an exported variable.
>
> Mike?

Its stable and lots of other components depend on it like f.e. the size of 
cpumasks.