From mboxrd@z Thu Jan 1 00:00:00 1970 From: Jamie Lokier Subject: Re: [Qemu-devel] qcow2 corruption observed, fixed by reverting old change Date: Wed, 11 Feb 2009 11:27:20 +0000 Message-ID: <20090211112720.GA31997@shareable.org> References: <20090211070049.GA27821@shareable.org> <4992A108.8070304@suse.de> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: qemu-devel@nongnu.org, kvm-devel To: Kevin Wolf Return-path: Received: from mail2.shareable.org ([80.68.89.115]:41314 "EHLO mail2.shareable.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754567AbZBKL1X (ORCPT ); Wed, 11 Feb 2009 06:27:23 -0500 Content-Disposition: inline In-Reply-To: <4992A108.8070304@suse.de> Sender: kvm-owner@vger.kernel.org List-ID: Kevin Wolf wrote: > Jamie Lokier schrieb: > > Although there are many ways to make Windows blue screen in KVM, in > > this case I've narrowed it down to the difference in > > qemu/block-qcow2.c between kvm-72 and kvm-73 (not -83). > > This must be one of SVN revisions 5003 to 5008 in upstream qemu. Can you > narrow it down to one of these? I certainly don't feel like reviewing > all of them once again. That's helpful, thanks. It's a production mail server which was affected, and it's being used at the moment. Not sure if I can narrow it down that easily :-) > Do I understand correctly that your image fails with the kvm-73 version > of block-qcow2.c and afterwards boots with kvm-72? So the image is not > really corrupted but it's more likely an IO error which brings the OS down? That's correct, it's always booted when trying again with kvm-72, or a later kvm with block-qcow2.c reverted. It might be an I/O error rather than corruption. Up to kvm-76, I/O errors aren't reported over the IDE driver. -- Jamie From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1LXDG4-000696-Ef for qemu-devel@nongnu.org; Wed, 11 Feb 2009 06:28:00 -0500 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1LXDG2-000689-EW for qemu-devel@nongnu.org; Wed, 11 Feb 2009 06:27:59 -0500 Received: from [199.232.76.173] (port=54971 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1LXDG2-00067l-8W for qemu-devel@nongnu.org; Wed, 11 Feb 2009 06:27:58 -0500 Received: from mail2.shareable.org ([80.68.89.115]:44195) by monty-python.gnu.org with esmtps (TLS-1.0:RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1LXDG0-00067k-Qm for qemu-devel@nongnu.org; Wed, 11 Feb 2009 06:27:57 -0500 Date: Wed, 11 Feb 2009 11:27:20 +0000 From: Jamie Lokier Subject: Re: [Qemu-devel] qcow2 corruption observed, fixed by reverting old change Message-ID: <20090211112720.GA31997@shareable.org> References: <20090211070049.GA27821@shareable.org> <4992A108.8070304@suse.de> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <4992A108.8070304@suse.de> Reply-To: qemu-devel@nongnu.org List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Kevin Wolf Cc: qemu-devel@nongnu.org, kvm-devel Kevin Wolf wrote: > Jamie Lokier schrieb: > > Although there are many ways to make Windows blue screen in KVM, in > > this case I've narrowed it down to the difference in > > qemu/block-qcow2.c between kvm-72 and kvm-73 (not -83). > > This must be one of SVN revisions 5003 to 5008 in upstream qemu. Can you > narrow it down to one of these? I certainly don't feel like reviewing > all of them once again. That's helpful, thanks. It's a production mail server which was affected, and it's being used at the moment. Not sure if I can narrow it down that easily :-) > Do I understand correctly that your image fails with the kvm-73 version > of block-qcow2.c and afterwards boots with kvm-72? So the image is not > really corrupted but it's more likely an IO error which brings the OS down? That's correct, it's always booted when trying again with kvm-72, or a later kvm with block-qcow2.c reverted. It might be an I/O error rather than corruption. Up to kvm-76, I/O errors aren't reported over the IDE driver. -- Jamie