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From:   Sandy Harris <sandyinchina@gmail.com>
Date:   Sat, 23 Apr 2022 10:24:07 +0800
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Subject: Re: [PATCH v5 11/11] random: insist on random_get_entropy() existing
 in order to simplify
To:     "Jason A. Donenfeld" <Jason@zx2c4.com>
Cc:     LKML <linux-kernel@vger.kernel.org>,
        Linux Crypto Mailing List <linux-crypto@vger.kernel.org>,
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On Sat, Apr 23, 2022 at 6:37 AM Jason A. Donenfeld <Jason@zx2c4.com> wrote:
>
> All platforms are now guaranteed to provide some value for
> random_get_entropy(). In case some bug leads to this not being so, we
> print a warning, ...

Would it make sense to test at compile time? If there is no hardware
RNG nor a cycle counter, then the kernel should be compiled with
the gcc latent entropy plugin. Generate a warning suggesting that,
or even an error insisting on it.