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Date:   Wed, 6 Dec 2023 12:28:50 -0800
From:   Kees Cook <keescook@chromium.org>
To:     Palmer Dabbelt <palmer@dabbelt.com>
Cc:     samitolvanen@google.com, Paul Walmsley <paul.walmsley@sifive.com>,
        aou@eecs.berkeley.edu, akpm@linux-foundation.org,
        linux-mm@kvack.org, linux-riscv@lists.infradead.org,
        llvm@lists.linux.dev, linux-kernel@vger.kernel.org
Subject: Re: [PATCH 0/2] riscv: Increase mmap_rnd_bits_max on Sv48/57
Message-ID: <202312061228.B953DE8CA@keescook>
References: <20230929211155.3910949-4-samitolvanen@google.com>
 <mhng-f0a257c6-a1f5-41db-b1c4-c178a77a79e9@palmer-ri-x1c9>
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On Wed, Dec 06, 2023 at 05:14:26AM -0800, Palmer Dabbelt wrote:
> On Fri, 29 Sep 2023 14:11:56 PDT (-0700), samitolvanen@google.com wrote:
> > Hi all,
> > 
> > We noticed that 64-bit RISC-V kernels limit mmap_rnd_bits to 24
> > even if the hardware supports a larger virtual address space size
> > [1]. These two patches allow mmap_rnd_bits_max to be changed during
> > init, and bumps up the maximum randomness if we end up setting up
> > 4/5-level paging at boot.
> 
> Sorry for missing this, I'm just poking through old stuff in patchwork.  As
> far as I can tell this is still relevant, the discussions are just on the
> mmap() bits (but we'd already screwed that one up and have since fixed it).
> 
> So
> 
> Reviewed-by: Palmer Dabbelt <palmer@rivosinc.com>
> Acked-by: Palmer Dabbelt <palmer@rivosinc.com>
> 
> in case someone else wants to take it, but I'm OK taking that MM patch with
> Kees' review.

Yes, thanks! Please do. I already +1ed it:
https://lore.kernel.org/all/202309291454.436E19663@keescook

-Kees

-- 
Kees Cook