From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:42192) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WlHYM-00043J-0V for qemu-devel@nongnu.org; Fri, 16 May 2014 08:48:03 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1WlHYH-0006Bo-3L for qemu-devel@nongnu.org; Fri, 16 May 2014 08:47:57 -0400 Received: from mx1.redhat.com ([209.132.183.28]:47963) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1WlHYG-0006Bk-R1 for qemu-devel@nongnu.org; Fri, 16 May 2014 08:47:53 -0400 Message-ID: <537608F5.2000901@redhat.com> Date: Fri, 16 May 2014 06:47:49 -0600 From: Eric Blake MIME-Version: 1.0 References: <5374E445.9070609@redhat.com> <20140515184103.GM8452@localhost.localdomain> <20140516093927.GC4508@noname.redhat.com> <20140516113546.GB11553@localhost.localdomain> In-Reply-To: <20140516113546.GB11553@localhost.localdomain> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="sgq8VKqUjopvDVHCTssEBrKlsreiilMjK" Subject: Re: [Qemu-devel] [PATCH 1/5] block: Auto-generate node_names for each BDS entry List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Jeff Cody , Kevin Wolf Cc: benoit.canet@irqsave.net, pkrempa@redhat.com, famz@redhat.com, qemu-devel@nongnu.org, stefanha@redhat.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --sgq8VKqUjopvDVHCTssEBrKlsreiilMjK Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 05/16/2014 05:35 AM, Jeff Cody wrote: >=20 > How does libvirt assign node-names to all the backing images in a > qcow2 chain, for example? We have the ability to do both command-line and QMP hotplug addition of drives where you can set backing.file.node-name (or is it backing.node-name?) for any element in a backing chain; libvirt just needs to be taught to use it. >=20 >=20 >> I'm not totally sure whether automatically generated node-names are >> a good idea, but I can see how they are useful with human monitor user= s >> which may not specify a node-name everywhere (I've used device_add >> without an ID often enough, only to find that I can't remove the devic= e >> any more). We should just make sure that they are really only used by >> human users. >> >=20 > I don't understand. What would be the downsides of having an > automatic guaranteed unique id assigned to each BDS? And why > restrict that to human users only? I'm not seeing downsides. >=20 > If you are worried about node-names potentially being undesired by the > user / management layer for some reason, how about this: we add a > drive option, to either enable or disable automatic node-name > generation for a particular drive? No, this is silly. If it defaults to off, then libvirt has to be taught to enable it - but if you are going to modify libvirt, you might as well modify it to set node names itself rather than to enable the option for automatic node names. If it defaults to on, no one has an incentive to disable it. --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --sgq8VKqUjopvDVHCTssEBrKlsreiilMjK Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJTdgj1AAoJEKeha0olJ0NqmAkH/3KsTMsYqKUrA+QDoc97DUNd Jk1b6yKj6nTFangKYGGDMSHGdftqCpNS/D48WE0P+aNDzJUPjnW5JYykKY/MHnJP KKTQD7U04Ulv+7qO0bk3aZcOLpBH9i78qcvmRVM2SY4niahrb7Kealr6W8ZvWY72 PaubBSt4GQHvADeCuMWer7UAEwz363mErw7mTNTxCtyOPHaWInxC3anG2xDBVF2Y jtwm9Tag7WouJr2NuMfXwPdqMvi5c+BTGE55CJA5IQmsLxG4wcqgeLMkT0pJpUSK DBSMHVT/bOcSroHHAS5lRksdOHp8HNvtWSwVhlsvAjXyTV7dfYjPhxoN+6k7B38= =ZXLf -----END PGP SIGNATURE----- --sgq8VKqUjopvDVHCTssEBrKlsreiilMjK--