From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:52507) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VR7Rl-0005Ps-Gg for qemu-devel@nongnu.org; Tue, 01 Oct 2013 17:25:37 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1VR7Rh-0004US-7T for qemu-devel@nongnu.org; Tue, 01 Oct 2013 17:25:33 -0400 Received: from mx1.redhat.com ([209.132.183.28]:12307) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1VR7Rg-0004TH-Ur for qemu-devel@nongnu.org; Tue, 01 Oct 2013 17:25:29 -0400 Message-ID: <524B3DBD.8020108@redhat.com> Date: Tue, 01 Oct 2013 15:25:17 -0600 From: Eric Blake MIME-Version: 1.0 References: <20131001210953.23207.28945.stgit@localhost.localdomain> In-Reply-To: <20131001210953.23207.28945.stgit@localhost.localdomain> Content-Type: multipart/signed; micalg=pgp-sha256; protocol="application/pgp-signature"; boundary="UpOisG8xRSRHR7Ve7IAwUUiQdDqU2drDd" Subject: Re: [Qemu-devel] [PATCH] qemu-ga: execute fsfreeze-freeze in reverse order of mounts List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Tomoki Sekiyama Cc: lcapitulino@redhat.com, seiji.aguchi@hds.com, qemu-devel@nongnu.org, mdroth@linux.vnet.ibm.com This is an OpenPGP/MIME signed message (RFC 4880 and 3156) --UpOisG8xRSRHR7Ve7IAwUUiQdDqU2drDd Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable On 10/01/2013 03:09 PM, Tomoki Sekiyama wrote: > Currently, fsfreeze-freeze may cause deadlock if a guest has loopback m= ounts > of image files in its disk; e.g.: >=20 > # mount | grep ^/ > /dev/vda1 / type ext4 (rw,noatime,seclabel,data=3Dordered) > /tmp/disk.img on /mnt type ext4 (rw,relatime,seclabel) >=20 > To avoid the deadlock, this freeze filesystems in reverse order of moun= ts. s/freeze/freezes/ >=20 > Signed-off-by: Tomoki Sekiyama > --- > qga/commands-posix.c | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) Thaw already worked in the forward direction; with your patch, this means thaw undoes the actions by freeze in the opposite order (last frozen is first thawed), which is also a good thing. Reviewed-by: Eric Blake --=20 Eric Blake eblake redhat com +1-919-301-3266 Libvirt virtualization library http://libvirt.org --UpOisG8xRSRHR7Ve7IAwUUiQdDqU2drDd Content-Type: application/pgp-signature; name="signature.asc" Content-Description: OpenPGP digital signature Content-Disposition: attachment; filename="signature.asc" -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.14 (GNU/Linux) Comment: Public key at http://people.redhat.com/eblake/eblake.gpg Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/ iQEcBAEBCAAGBQJSSz29AAoJEKeha0olJ0Nq/y8H/3UC7/Y9cm4JwrSFJibBiUP9 Lva92L+Fg839l5VhJYaV23SAFBlLyVHwWgTB32Wm+QPLtuVlS0yjRHMTpFOWUdQT MlTX6/Y0D8UwNaH6JHH8LBxCEnjWJ+B8CexALtqMal01rJzdSuqDhtVtCmKaXuii hYuD/vGRJCIwyBoI3tTQlNYwMcWJ7DzhyJyXGriGf4zcdn6yQr5CYMCb3q/yRLTH lpvtNn7rlFaASVPRm/SLcMbeC2EkGVpAKl9drdBqj3o0rzO6xLlfxHsEB4EB1Fjd jjKQeRa4s9VG17XkhVkKQsQhnh52yaI/NEG67zhFP+/G6eZVmoeDLjpjNjvRsws= =waSv -----END PGP SIGNATURE----- --UpOisG8xRSRHR7Ve7IAwUUiQdDqU2drDd--