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Date:   Mon, 30 Mar 2020 14:37:02 +0100
From:   Will Deacon <will@kernel.org>
To:     George Spelvin <lkml@sdf.org>
Cc:     linux-kernel@vger.kernel.org, Hsin-Yi Wang <hsinyi@chromium.org>,
        Catalin Marinas <catalin.marinas@arm.com>,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [RFC PATCH v1 39/50] arm: kexec_file: Avoid temp buffer for RNG
 seed
Message-ID: <20200330133701.GA10633@willie-the-truck>
References: <202003281643.02SGhMtr029198@sdf.org>
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On Tue, Dec 10, 2019 at 10:45:27AM -0500, George Spelvin wrote:
> After using get_random_bytes(), you want to wipe the buffer
> afterward so the seed remains secret.
> 
> In this case, we can eliminate the temporary buffer entirely.
> fdt_setprop_placeholder returns a pointer to the property value
> buffer, allowing us to put the random data directy in there without

s/directy/directly/

> using a temporary buffer at all.  Faster and less stack all in one.
> 
> Signed-off-by: George Spelvin <lkml@sdf.org>
> Cc: Hsin-Yi Wang <hsinyi@chromium.org>
> Cc: Catalin Marinas <catalin.marinas@arm.com>
> Cc: Will Deacon <will@kernel.org>
> Cc: linux-arm-kernel@lists.infradead.org
> ---
>  arch/arm64/kernel/machine_kexec_file.c | 8 ++++----
>  1 file changed, 4 insertions(+), 4 deletions(-)

Acked-by: Will Deacon <will@kernel.org>

Please let me know if you'd like this queued via the arm64 tree, as it
appears to be independent of the rest of this series.

Will