From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1O4WQ2-0000yq-75 for qemu-devel@nongnu.org; Wed, 21 Apr 2010 05:40:30 -0400 Received: from [140.186.70.92] (port=41188 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1O4WPz-0000xa-7Z for qemu-devel@nongnu.org; Wed, 21 Apr 2010 05:40:28 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.69) (envelope-from ) id 1O4WPt-00062Z-3P for qemu-devel@nongnu.org; Wed, 21 Apr 2010 05:40:22 -0400 Received: from mail2.shareable.org ([80.68.89.115]:35859) by eggs.gnu.org with esmtp (Exim 4.69) (envelope-from ) id 1O4WPs-00061F-TU for qemu-devel@nongnu.org; Wed, 21 Apr 2010 05:40:21 -0400 Date: Wed, 21 Apr 2010 10:40:07 +0100 From: Jamie Lokier Subject: Re: [Qemu-devel] [PATCH 2/2] VirtIO RNG Message-ID: <20100421094007.GC13114@shareable.org> References: <4BB2053C.6000701@collabora.co.uk> <201004031606.26893.paul@codesourcery.com> <4BC482A6.4040504@collabora.co.uk> <201004131632.25820.paul@codesourcery.com> <4BCDC51F.2030205@collabora.co.uk> <20100420161302.GA11723@shareable.org> <4BCE061B.2030506@collabora.co.uk> <20100420205654.GI11723@shareable.org> <4BCE1D3B.7000306@collabora.co.uk> <4BCEAC99.8000206@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4BCEAC99.8000206@redhat.com> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: Ian Molton , Paul Brook , qemu-devel@nongnu.org Gerd Hoffmann wrote: > On 04/20/10 23:31, Ian Molton wrote: > > >Using virtio-rng means that the data is going into the guest > >kernels hwrng subsystem. > > Which is *the* major advantage of the virtio-rng driver. In case the > guest kernel is recent enougth to have support for it, it will > JustWork[tm]. No need for guest configuration, no need for some > userspace tool. I'd like to see this driver being merged. > > With any kind of serial port (be it a emulated 16550 or virtio-serial) > you'll need some daemon running inside the guest grabbing entropy data > from the port and feeding it back into the kernel. That's a bunch of false assumptions. There's no reason a hwrng connector to virtio-serial could not be automatic in a similar way to the console. But enough of that: It's history now; the guest virtio-rng has existed for more than a year. It is also amazingly short and simple. Yay for Rusty! I don't object to virtio-rng; I think it's fine in principle and would be happy to see the existing guests which have a virtio-rng driver make use of it. A bit of overlapping functionality is rife in emulators anyway :-) -- Jamie