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From:   =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@kernel.org>
To:     Alexandre Ghiti <alex@ghiti.fr>,
        Paul Walmsley <paul.walmsley@sifive.com>,
        Palmer Dabbelt <palmer@dabbelt.com>,
        Albert Ou <aou@eecs.berkeley.edu>,
        linux-riscv@lists.infradead.org
Cc:     =?utf-8?B?QmrDtnJuIFTDtnBlbA==?= <bjorn@rivosinc.com>,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] riscv: mm: Proper page permissions after initmem free
In-Reply-To: <b82f4580-76a0-e02b-05c8-4a89e576da0c@ghiti.fr>
References: <20221112113543.3165646-1-bjorn@kernel.org>
 <b82f4580-76a0-e02b-05c8-4a89e576da0c@ghiti.fr>
Date:   Mon, 14 Nov 2022 16:25:49 +0100
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Alexandre Ghiti <alex@ghiti.fr> writes:

>> +		set_kernel_memory(__init_begin, __init_end, set_memory_rw_nx);
>
>
> That's nits but for 64-bit kernels, do we really want to make the kernel=
=20
> mapping writable? I think catching a write access here would be better=20
> because IMO that should not happen.

Thanks for having a look!

Hmm, so what you're suggesting is a "set_memory_r_nx" for CONFIG_64BIT?
What do other archs do? Is it worth the extra ifdef clutter?


Bj=C3=B6rn