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From:   Linus Torvalds <torvalds@linux-foundation.org>
Date:   Wed, 20 Sep 2023 13:41:23 -0700
Message-ID: <CAHk-=wh+nAmcXV=Xz6fkDpazne+n+iFfGsnS=p9PjVLiEjiSvQ@mail.gmail.com>
Subject: Re: [RFC] Should writes to /dev/urandom immediately affect reads?
To:     Eric Biggers <ebiggers@kernel.org>
Cc:     "Jason A. Donenfeld" <Jason@zx2c4.com>,
        linux-kernel@vger.kernel.org, linux-crypto@vger.kernel.org,
        "Theodore Ts'o" <tytso@mit.edu>,
        Dominik Brodowski <linux@dominikbrodowski.net>,
        Jann Horn <jannh@google.com>
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On Wed, 20 Sept 2023 at 13:32, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> It was why I also asked about entropy. Because *if* you argue that the
> user-space write contains entropy, then that would be a reason.

To clarify - the jitter entropy question was related to that same
basic issue: if this was meant to be a way to mitigate the lack of
jitter entropy on some platform you care about, that would again
possibly be a reason to care.

Considering that we apparently haven't cared for the last 7 years, I'm
still a bit surprised, but whatever.

What I *don't* want is just more voodoo discussions about /dev/*random
behavior that doesn't have a technical reason for it.

                Linus