From: Sandy Harris <sandyinchina@gmail.com>
Subject: Re: [PATCH] random: add blocking facility to urandom
Date: Thu, 8 Sep 2011 10:43:38 +0800
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Cc: "Ted Ts'o" <tytso@mit.edu>, Sasha Levin <levinsasha928@gmail.com>,
	linux-crypto@vger.kernel.org, Matt Mackall <mpm@selenic.com>,
	Neil Horman <nhorman@redhat.com>,
	Herbert Xu <herbert.xu@redhat.com>,
	Steve Grubb <sgrubb@redhat.com>,
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To: Jarod Wilson <jarod@redhat.com>
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Jarod Wilson <jarod@redhat.com> wrote:

> Ted Ts'o wrote:

>> Yeah, but there are userspace programs that depend on urandom not
>> blocking... so your proposed change would break them.
>> ...

> But only if you've set the sysctl to a non-zero value, ...
>
> But again, I want to stress that out of the box, there's absolutely no
> change to the way urandom behaves, no blocking, this *only* kicks in if you
> twiddle the sysctl because you have some sort of security requirement that
> mandates it.

So it only breaks things on systems with high security requirements?