From: Sandy Harris <sandyinchina@gmail.com>
Subject: Re: [PATCH v4 2/6] random: Async and sync API for accessing kernel_pool
Date: Mon, 4 May 2015 06:22:04 -0400
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Cc: Herbert Xu <herbert@gondor.apana.org.au>,
	Paul Bolle <pebolle@tiscali.it>,
	Andreas Steffen <andreas.steffen@strongswan.org>,
	"Theodore Ts'o" <tytso@mit.edu>,
	LKML <linux-kernel@vger.kernel.org>, linux-crypto@vger.kernel.org
To: Stephan Mueller <smueller@chronox.de>
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On Sun, May 3, 2015 at 11:33 AM, Stephan Mueller <smueller@chronox.de> wrote:

> The kernel_pool is intended to be the in-kernel equivalent to the
> blocking_pool, i.e. requests for random data may be blocked if
> insufficient entropy is present.

I cannot see any reason this would be useful, let alone necessary.

Of course /dev/random should block and it seems to me there is a good
argument for making both /dev/urandom and get_random_bytes() block
until there is emough entropy to seed them well. For everything else,
though, a properly seeded PRNG seems adequate so there is no reason to
block.