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Date: Fri, 7 Feb 2025 15:33:24 +0100
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Subject: Re: [RFC PATCH v3 08/15] mm: Introduce kernel_pgtables_set_pkey()
To: Linus Walleij <linus.walleij@linaro.org>
Cc: linux-hardening@vger.kernel.org, linux-kernel@vger.kernel.org,
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References: <20250203101839.1223008-1-kevin.brodsky@arm.com>
 <20250203101839.1223008-9-kevin.brodsky@arm.com>
 <CACRpkdZ_eGsfZh2vkG8dtSyZDbStMfDUuj7s7TQ4FcDwThJVkg@mail.gmail.com>
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From: Kevin Brodsky <kevin.brodsky@arm.com>
In-Reply-To: <CACRpkdZ_eGsfZh2vkG8dtSyZDbStMfDUuj7s7TQ4FcDwThJVkg@mail.gmail.com>
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On 06/02/2025 20:01, Linus Walleij wrote:
>> +static int set_page_pkey(void *p, int pkey)
>> +static int set_pkey_pte(pmd_t *pmd, int pkey)
>> +static int set_pkey_pmd(pud_t *pud, int pkey)
>> +static int set_pkey_pud(p4d_t *p4d, int pkey)
>> +static int set_pkey_p4d(pgd_t *pgd, int pkey)
>> +int kernel_pgtables_set_pkey(int pkey)
> Aren't these all discardable after boot, so the whole set should
> be tagged with __init?

Good point, I was thinking of this function as a relatively generic one
but in reality there's probably no use for it after boot. In any case
it's only called from a function marked __init at the moment, so it's
safe to mark all those as __init too.

> Other than that it LGTM.

Thank you for the review!

- Kevin