From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36383) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1YT76I-00034b-6m for qemu-devel@nongnu.org; Wed, 04 Mar 2015 06:04:30 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1YT76C-00075m-8p for qemu-devel@nongnu.org; Wed, 04 Mar 2015 06:04:26 -0500 Date: Wed, 4 Mar 2015 12:04:04 +0100 From: Kevin Wolf Message-ID: <20150304110404.GH3465@noname.str.redhat.com> References: <1425066879-27326-1-git-send-email-mreitz@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1425066879-27326-1-git-send-email-mreitz@redhat.com> Subject: Re: [Qemu-devel] [PATCH v3] block/vdi: Add locking for parallel requests List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Max Reitz Cc: Stefan Weil , Stefan Hajnoczi , qemu-devel@nongnu.org, qemu-block@nongnu.org, Paolo Bonzini Am 27.02.2015 um 20:54 hat Max Reitz geschrieben: > When allocating a new cluster, the first write to it must be the one > doing the allocation, because that one pads its write request to the > cluster size; if another write to that cluster is executed before it, > that write will be overwritten due to the padding. > > See https://bugs.launchpad.net/qemu/+bug/1422307 for what can go wrong > without this patch. > > Cc: qemu-stable > Signed-off-by: Max Reitz > --- > v3: Hopefully finally found the real issue which causes the problems > described in the bug report; at least it sounds very reasonable and > I can no longer reproduce any of the issues described there. > Thank you, Paolo and Stefan! Thanks, applied to the block branch. Kevin