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Subject: Re: [PATCH v9 05/18] arm64: trans_pgd: pass NULL instead of init_mm
 to *_populate functions
To:     Pavel Tatashin <pasha.tatashin@soleen.com>
References: <20200326032420.27220-1-pasha.tatashin@soleen.com>
 <20200326032420.27220-6-pasha.tatashin@soleen.com>
From:   James Morse <james.morse@arm.com>
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        kexec@lists.infradead.org, linux-kernel@vger.kernel.org,
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Date:   Wed, 29 Apr 2020 18:01:11 +0100
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Hi Pavel,

On 26/03/2020 03:24, Pavel Tatashin wrote:
> trans_pgd_* should be independent from mm context because the tables that
> are created by this code are used when there are no mm context around, as
> it is between kernels. Simply replace mm_init's with NULL.

arm64's p?d_populate() helpers don't use the mm parameter, so it doesn't make any
difference. This was originally done so that if we ever needed anything from the mm, we
didn't get a NULL dereference or EL0 behaviour due to a future '!= &init_mm'.

If you think it matters,
Acked-by: James Morse <james.morse@arm.com>


Thanks,

James