From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1MLdnl-00016s-6e for qemu-devel@nongnu.org; Tue, 30 Jun 2009 09:55:13 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1MLdng-0000vh-Ka for qemu-devel@nongnu.org; Tue, 30 Jun 2009 09:55:12 -0400 Received: from [199.232.76.173] (port=35614 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1MLdng-0000vN-9O for qemu-devel@nongnu.org; Tue, 30 Jun 2009 09:55:08 -0400 Received: from mx2.redhat.com ([66.187.237.31]:40753) by monty-python.gnu.org with esmtp (Exim 4.60) (envelope-from ) id 1MLdnf-000432-Rl for qemu-devel@nongnu.org; Tue, 30 Jun 2009 09:55:08 -0400 Message-ID: <4A4A18F6.50301@redhat.com> Date: Tue, 30 Jun 2009 15:53:58 +0200 From: Kevin Wolf MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH] Warn if a qcow (not qcow2) file is opened References: <1246284289-25394-1-git-send-email-avi@redhat.com> <4A49CE00.4090504@redhat.com> <4A4A13F7.8050904@codemonkey.ws> In-Reply-To: <4A4A13F7.8050904@codemonkey.ws> Content-Type: text/plain; charset=ISO-8859-15 Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: Avi Kivity , kvm@vger.kernel.org, qemu-devel@nongnu.org Anthony Liguori schrieb: > Kevin Wolf wrote: >> Avi Kivity schrieb: >> >>> The qcow block driver format is no longer maintained and likely contains >>> serious data corruptors. Urge users to stay away for it, and advertise >>> the new and improved replacement. >>> >>> Signed-off-by: Avi Kivity >>> >> vvfat is using qcow internally, so the warning will appear there, too. >> Not that warning against vvfat would be a bad thing, but this error >> message could be confusing. >> >> Maybe we're lucky enough and vvfat survives a s/qcow/qcow2/, but I >> really never wanted to touch that code... >> > > I'm not sure how I feel about this. Can we prove qcow is broken? Is it > only broken for writes and not reads? > > If we're printing a warning, does that mean we want to deprecate qcow > and eventually remove it (or remove write support, at least)? I haven't commented on the intention of deprecating qcow1, I'm not sure either. But the bug that turned up yesterday was present for a month and nobody saw it. So I guess we can take that as a sign that qcow isn't really used that much any more. On the other hand, I think maintaining qcow1 isn't that hard. It won't get new features, so we'll not have a whole lot of changes. We must test it from time to time. And when it comes to fixing, I think qcow1 is much easier for us than, say, VMDK. Kevin