From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MjKAq-0008LI-BO for qemu-devel@nongnu.org; Thu, 03 Sep 2009 17:48:56 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MjKAl-0008Ij-LU for qemu-devel@nongnu.org; Thu, 03 Sep 2009 17:48:55 -0400 Received: from [199.232.76.173] (port=38352 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MjKAl-0008Id-Bm for qemu-devel@nongnu.org; Thu, 03 Sep 2009 17:48:51 -0400 Received: from mail-bw0-f227.google.com ([209.85.218.227]:42982) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MjKAk-0003Nj-US for qemu-devel@nongnu.org; Thu, 03 Sep 2009 17:48:51 -0400 Received: by bwz27 with SMTP id 27so276533bwz.34 for ; Thu, 03 Sep 2009 14:48:49 -0700 (PDT) MIME-Version: 1.0 Sender: dustin.kirkland@gmail.com In-Reply-To: <1252008114.3084.136.camel@blaa> References: <1252008114.3084.136.camel@blaa> Date: Thu, 3 Sep 2009 16:48:49 -0500 Message-ID: From: Dustin Kirkland Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Subject: [Qemu-devel] Re: [PATCH] qemu-kvm: fix segfault when running kvm without /dev/kvm, falling back to non-accelerated mode List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Mark McLoughlin Cc: qemu-devel@nongnu.org, kvm@vger.kernel.org On Thu, Sep 3, 2009 at 3:01 PM, Mark McLoughlin wrote: > On Thu, 2009-09-03 at 12:31 -0500, Dustin Kirkland wrote: >> qemu-kvm: fix segfault when running kvm without /dev/kvm, falling back >> to non-accelerated mode >> >> We're seeing segfaults on systems without access to /dev/kvm. =A0It >> looks like the global kvm_allowed is being set just a little too late >> in vl.c. =A0This patch moves the kvm initialization a bit higher in the >> vl.c main, just after options processing, and solves the segfaults. >> We're carrying this patch in Ubuntu 9.10 Alpha. =A0Please apply >> upstream, or advise if and why this might not be the optimal solution. > > Ah discussion about an alternative fix for this fizzled out recently: > > =A0http://www.mail-archive.com/kvm@vger.kernel.org/msg19890.html Ah, thanks Mark. In that thread, I found Daniel's suggestion the most reasonable, and user-friendly: On Mon, Jul 27, 2009 at 1:44 PM, Daniel P. Berrange wr= ote: > Well, we could go for logic like: > > * No arg given =3D> try kvm, try kqemu, try tcg > * --accelmode arg given =3D> try $arg, and fail if unavailable > > then libvirt would simply always supply --accelmode for all VMs, > while people running qemu manually would get best available :-Dustin