From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:41664) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ZsEJr-0005NB-NE for qemu-devel@nongnu.org; Fri, 30 Oct 2015 14:22:36 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ZsEJm-0000Qr-4Q for qemu-devel@nongnu.org; Fri, 30 Oct 2015 14:22:31 -0400 References: From: Max Reitz Message-ID: <5633B553.7080600@redhat.com> Date: Fri, 30 Oct 2015 19:22:11 +0100 MIME-Version: 1.0 In-Reply-To: Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="EclPhI1n0gCtwDOiXjloJccWOIXbrI4SF" Subject: Re: [Qemu-devel] [PATCH 0/2] Don't allow snapshots if the overlay has parent nodes List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Alberto Garcia , qemu-devel@nongnu.org Cc: Kevin Wolf , Stefan Hajnoczi , qemu-block@nongnu.org, Markus Armbruster This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --EclPhI1n0gCtwDOiXjloJccWOIXbrI4SF Content-Type: text/plain; charset=iso-8859-15 Content-Transfer-Encoding: quoted-printable On 29.10.2015 14:00, Alberto Garcia wrote: > There are several sanity checks for the 'blockdev-snapshot' command, > but none covers the use of a file BDS as the overlay node. >=20 > { 'execute': 'blockdev-add', 'arguments': > { 'options': { 'driver': 'qcow2', > 'node-name': 'new0', > 'file': { 'driver': 'file', > 'filename': 'new.qcow2', > 'node-name': 'file0' } } } } >=20 > { 'execute': 'blockdev-snapshot', 'arguments': > { 'node': 'virtio0', > 'overlay': 'file0' } } Well, I don't think the problem here is that file0 has a parent. For instance, you might want to use a qcow2 child node of a quorum BDS as the new overlay; or in the future, you may want to use a snapshot node which has some filters on top of it. To me, the problem is that file0 is driven by the driver "file" which does not support backing files. I think that's what should be fixed. Max > This series fixes that and adds a new test case. This of course > depends on the 'blockdev-snapshot' series: >=20 > https://lists.gnu.org/archive/html/qemu-block/2015-10/msg00974.html >=20 > I anyway wonder if it wouldn't be a good idea to have regular op > blockers in all file BDSs? >=20 > Regards, >=20 > Berto >=20 > Alberto Garcia (2): > block: Don't allow snapshots if the overlay has parent nodes > block: test 'blockdev-snapshot' using a file BDS as the overlay >=20 > blockdev.c | 5 +++++ > tests/qemu-iotests/085 | 12 +++++++++++- > tests/qemu-iotests/085.out | 4 ++++ > 3 files changed, 20 insertions(+), 1 deletion(-) >=20 --EclPhI1n0gCtwDOiXjloJccWOIXbrI4SF Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v2 iQEcBAEBCAAGBQJWM7VTAAoJEDuxQgLoOKyt3KgIAIl7dF61yiaJj+QiGjF3CrZ9 eGGKU1c0R0z2oNxBP1xk8BO3O/Ka8BT4Qm6Erj+70ZLyIM4OaagS+9RLFauNeeaZ MvlyeeQrJ7TvEHf8YaypOjRfTOwx5fIuOeTzsq0Xu8YRiJX2t5t0O/fALMsPHFNz GenKAUeEYu4RLEBCo7LvF8oUyKz3Bu8z1o2g2rW+ZCHTVNlfK0NFYWouXqqxowCK N4q58wX1jST3Ts0yhVeIxgNJjNd1T7V11dWpe1v5kNC4D41Kq4Yo2lzw2WGs9W8W 0shhw6ATgv2NQbxGdXdnkSrJBxjSKJkp4+/KIDJIJcLeXLjtg/ExRgLd+530EbY= =REU6 -----END PGP SIGNATURE----- --EclPhI1n0gCtwDOiXjloJccWOIXbrI4SF--