From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-1.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 5837FC04AA7 for ; Mon, 13 May 2019 12:14:45 +0000 (UTC) Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPS id 2C21B20879 for ; Mon, 13 May 2019 12:14:45 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 2C21B20879 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=redhat.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Received: from localhost ([127.0.0.1]:56361 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQ9qu-0005mC-4U for qemu-devel@archiver.kernel.org; Mon, 13 May 2019 08:14:44 -0400 Received: from eggs.gnu.org ([209.51.188.92]:43400) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1hQ9q6-0005SL-DY for qemu-devel@nongnu.org; Mon, 13 May 2019 08:13:55 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1hQ9q4-0001Lc-38 for qemu-devel@nongnu.org; Mon, 13 May 2019 08:13:54 -0400 Received: from mx1.redhat.com ([209.132.183.28]:36396) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1hQ9q3-0001LG-Rq for qemu-devel@nongnu.org; Mon, 13 May 2019 08:13:52 -0400 Received: from smtp.corp.redhat.com (int-mx08.intmail.prod.int.phx2.redhat.com [10.5.11.23]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id C40FD7E427; Mon, 13 May 2019 12:13:50 +0000 (UTC) Received: from blackfin.pond.sub.org (ovpn-116-28.ams2.redhat.com [10.36.116.28]) by smtp.corp.redhat.com (Postfix) with ESMTPS id 75B0F19C67; Mon, 13 May 2019 12:13:48 +0000 (UTC) Received: by blackfin.pond.sub.org (Postfix, from userid 1000) id E4CDA11385E4; Mon, 13 May 2019 14:13:46 +0200 (CEST) From: Markus Armbruster To: Kashyap Chamarthy References: <20190510134203.24012-1-lvivier@redhat.com> <20190512142108-mutt-send-email-mst@kernel.org> <3779f01f-8a5b-0785-254b-d1a4cfdf593c@redhat.com> <20190513084945.GA15247@paraplu> Date: Mon, 13 May 2019 14:13:46 +0200 In-Reply-To: <20190513084945.GA15247@paraplu> (Kashyap Chamarthy's message of "Mon, 13 May 2019 10:49:45 +0200") Message-ID: <871s128scl.fsf@dusky.pond.sub.org> User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.1 (gnu/linux) MIME-Version: 1.0 Content-Type: text/plain X-Scanned-By: MIMEDefang 2.84 on 10.5.11.23 X-Greylist: Sender IP whitelisted, not delayed by milter-greylist-4.5.16 (mx1.redhat.com [10.5.110.27]); Mon, 13 May 2019 12:13:50 +0000 (UTC) X-detected-operating-system: by eggs.gnu.org: GNU/Linux 2.2.x-3.x [generic] X-Received-From: 209.132.183.28 Subject: Re: [Qemu-devel] [PATCH v3 0/3] rng-builtin: add an RNG backend that uses qemu_guest_getrandom() X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Laurent Vivier , "Daniel P. =?utf-8?Q?Berrang?= =?utf-8?Q?=C3=A9?=" , "Michael S. Tsirkin" , Amit Shah , Richard Henderson , qemu-devel@nongnu.org, "Richard W . M . Jones" Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Kashyap Chamarthy writes: > On Mon, May 13, 2019 at 08:36:23AM +0200, Laurent Vivier wrote: >> On 12/05/2019 20:21, Michael S. Tsirkin wrote: > > [...] > >> > > Kashyap Chamarthy (1): >> > > VirtIO-RNG: Update default entropy source to `/dev/urandom` >> > > >> > > Laurent Vivier (2): >> > > rng-builtin: add an RNG backend that uses qemu_guest_getrandom() >> > > virtio-rng: change default backend to rng-builtin >> > >> > >> > OK pls address Marku's comment on commit msg and I will merge. >> >> Kashyap, >> >> as this patch is from you, do you agree? > > Yes. > >> If so, I can update the message and send a new version of the series >> (or you canr esend your patch alone if you prefer). > > Please go ahead and add it, the below is the text (from Dan/Markus): > > What about other OSes? > ---------------------- > > `/dev/urandom` exists and works on OS-X, FreeBSD, DragonFlyBSD, NetBSD > and OpenBSD, which cover all the non-Linux platforms we explicitly > support, aside from Windows. > > On Windows `/dev/random` doesn't work either so we don't regress. > This is actually another argument in favour of using the newly > proposed 'rng-builtin' backend by default, as that will work on > Windows. Additionally, please insert "on Linux" into the first paragraph, like this: When QEMU exposes a VirtIO-RNG device to the guest, that device needs a source of entropy, and that source needs to be "non-blocking", like `/dev/urandom`. However, currently QEMU defaults to the problematic `/dev/random`, which on Linux is "blocking" (as in, it waits until sufficient entropy is available).