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Message-ID: <9a028efb77ae662fe8eabcf2ffb5a64214f07418.camel@sipsolutions.net>
Subject: Re: [PATCH] um: seed rng using host OS rng
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        "Jason A. Donenfeld" <Jason@zx2c4.com>,
        linux-um@lists.infradead.org, linux-kernel@vger.kernel.org
Cc:     stable@vger.kernel.org
Date:   Wed, 13 Jul 2022 09:03:31 +0200
In-Reply-To: <d20a629c-8c15-ca8a-c34a-c5c084dbee03@cambridgegreys.com>
References: <20220712232738.77737-1-Jason@zx2c4.com>
         <d20a629c-8c15-ca8a-c34a-c5c084dbee03@cambridgegreys.com>
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On Wed, 2022-07-13 at 07:58 +0100, Anton Ivanov wrote:
>=20
> IIRC UML RNG device reads directly from host.

Yes, but that's a /dev/hwrng device, so you still need some userspace to
feed entropy from that into /dev/random.

> If you are using UMLs own /dev/random you are effectively using the host=
=20
> one.

> So unless I am mistaken, you need extra randomness only if you do not=20
> have UMLs /dev/random compiled in.

No, neither of those is true.

johannes