From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MeWWV-0001ml-CK for qemu-devel@nongnu.org; Fri, 21 Aug 2009 11:59:27 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MeWWP-0001jK-SA for qemu-devel@nongnu.org; Fri, 21 Aug 2009 11:59:25 -0400 Received: from [199.232.76.173] (port=39059 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MeWWP-0001jH-MR for qemu-devel@nongnu.org; Fri, 21 Aug 2009 11:59:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12371) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MeWWP-0006zU-13 for qemu-devel@nongnu.org; Fri, 21 Aug 2009 11:59:21 -0400 Received: from int-mx04.intmail.prod.int.phx2.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.17]) by mx1.redhat.com (8.13.8/8.13.8) with ESMTP id n7LFxJc4010836 for ; Fri, 21 Aug 2009 11:59:19 -0400 Subject: Re: [Qemu-devel] [PATCH] switch balloon initialization to -device. References: <1250238862-1408-1-git-send-email-kraxel@redhat.com> <87tz0alogm.fsf@pike.pond.sub.org> <4A8537FA.9090404@redhat.com> From: Markus Armbruster Date: Fri, 21 Aug 2009 17:59:17 +0200 In-Reply-To: <4A8537FA.9090404@redhat.com> (Gerd Hoffmann's message of "Fri\, 14 Aug 2009 12\:10\:02 +0200") Message-ID: <87fxbl2m5m.fsf@pike.pond.sub.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Gerd Hoffmann Cc: qemu-devel@nongnu.org Gerd Hoffmann writes: > On 08/14/09 11:44, Markus Armbruster wrote: >> Gerd Hoffmann writes: >> >>> With that patch applied "-balloon virtio,args" becomes a shortcut for >>> "-device virtio-balloon-pci,args". >>> >>> Side effects: >>> - ballon device gains support for id=. >>> - ballon device is off by default now. >>> - initialization order changes, which may in different pci slot >>> assignment depending on the VM configuration. >>> >>> Signed-off-by: Gerd Hoffmann >> >> Looks good on quick inspection (gotta run), just one question: what >> happens when I (stupidly) do -balloon virtio,driver=e1000 ? Question >> might apply to plain -device before this patch as well. > > QemuOpts allows overwriting, so who is written last will win. > Write order is undefined, so don't try that at home ;) > > Behavior of the current code: > > -balloon virtio,driver=e1000 will give you a balloon device. > -device virtio-blk-pci,driver=e1000 will give you a e1000. Ugly. Not sure it's worth fixing.