From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:38181) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1e1fqm-0006mZ-1z for qemu-devel@nongnu.org; Mon, 09 Oct 2017 17:44:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1e1fqi-0002H6-3z for qemu-devel@nongnu.org; Mon, 09 Oct 2017 17:44:36 -0400 Received: from mx1.redhat.com ([209.132.183.28]:44202) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1e1fqh-0002Gq-TQ for qemu-devel@nongnu.org; Mon, 09 Oct 2017 17:44:32 -0400 Received: from smtp.corp.redhat.com (int-mx05.intmail.prod.int.phx2.redhat.com [10.5.11.15]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 8A7A12576C for ; Mon, 9 Oct 2017 21:44:30 +0000 (UTC) Date: Tue, 10 Oct 2017 00:44:26 +0300 From: "Michael S. Tsirkin" Message-ID: <20171010003951-mutt-send-email-mst@kernel.org> References: <20170911165929.2791-1-marcandre.lureau@redhat.com> <20170911165929.2791-3-marcandre.lureau@redhat.com> <20171009110336.GA17824@redhat.com> <20171009144344.38bbd1e9@nial.brq.redhat.com> <20171009130218.GK2954@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=iso-8859-1 Content-Disposition: inline In-Reply-To: <20171009130218.GK2954@redhat.com> Content-Transfer-Encoding: quoted-printable Subject: Re: [Qemu-devel] [PATCH v6 2/7] hw/misc: add vmcoreinfo device List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Igor Mammedov , =?iso-8859-1?Q?Marc-Andr=E9?= Lureau , ehabkost@redhat.com, qemu-devel@nongnu.org, anderson@redhat.com, lersek@redhat.com On Mon, Oct 09, 2017 at 02:02:18PM +0100, Daniel P. Berrange wrote: > On Mon, Oct 09, 2017 at 02:43:44PM +0200, Igor Mammedov wrote: > > On Mon, 9 Oct 2017 12:03:36 +0100 > > "Daniel P. Berrange" wrote: > >=20 > > > On Mon, Sep 11, 2017 at 06:59:24PM +0200, Marc-Andr=E9 Lureau wrote= : > > > > See docs/specs/vmcoreinfo.txt for details. > > > >=20 > > > > "etc/vmcoreinfo" fw_cfg entry is added when using "-device vmcore= info". =20 > > >=20 > > > I'm wondering if you considered just adding the entry to fw_cfg by > > > default, without requiring any -device arg ? Unless I'm misundersta= nding, > > > this doesn't feel like a device to me - its just a well known bucke= t > > > in fw_cfg IIUC ? Obviously its existance would need to be tied to > > > the latest machine type for ABI reasons though. The benefit of this > > > is that it would "just work" without us having to plumb it through = to > > > all the downstream applications that use QEMU for mgmt guest (OpenS= tack, > > > oVirt, GNOME Boxes, virt-manager, and countless other mgmt apps). > > it follows model set by pvpanic device, it's easier to manage from mi= gration > > POV, one could use it even for old machine types with new qemu (just = by adding > > device, it makes instance not backwards migratable to old qemu but sh= ould work > > for forward migration) and if user doesn't need it, device could be j= ust omitted > > from CLI. >=20 > Sure but it means that in effect no one will have this functionality en= abled > for several years. pvpanic has been around a long time and I rarely see= it > present in configured guests :-( >=20 >=20 > Regards, > Daniel libvirt runs with -nodefaults, right? I'd argue pretty strongly -nodefaul= ts shouldn't add optional devices anyway. So it's up to you guys, you can add it to VMs by default if you want to. > --=20 > |: https://berrange.com -o- https://www.flickr.com/photos/dberr= ange :| > |: https://libvirt.org -o- https://fstop138.berrange= .com :| > |: https://entangle-photo.org -o- https://www.instagram.com/dberr= ange :|