From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=55722 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PnTcg-0007jg-37 for qemu-devel@nongnu.org; Thu, 10 Feb 2011 05:19:39 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PnTcY-0002qB-Sr for qemu-devel@nongnu.org; Thu, 10 Feb 2011 05:19:32 -0500 Received: from mx1.redhat.com ([209.132.183.28]:10334) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PnTcY-0002pz-Ld for qemu-devel@nongnu.org; Thu, 10 Feb 2011 05:19:30 -0500 Date: Thu, 10 Feb 2011 10:18:56 +0000 From: "Daniel P. Berrange" Subject: Re: [Qemu-devel] [PATCH 02/18] Introduce read() to FdMigrationState. Message-ID: <20110210101856.GE2842@redhat.com> References: <1297330258-20494-1-git-send-email-tamura.yoshiaki@lab.ntt.co.jp> <1297330258-20494-3-git-send-email-tamura.yoshiaki@lab.ntt.co.jp> <4D53B5B9.8070509@codemonkey.ws> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <4D53B5B9.8070509@codemonkey.ws> Reply-To: "Daniel P. Berrange" List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Anthony Liguori Cc: kwolf@redhat.com, aliguori@us.ibm.com, mtosatti@redhat.com, ananth@in.ibm.com, kvm@vger.kernel.org, mst@redhat.com, dlaor@redhat.com, Yoshiaki Tamura , qemu-devel@nongnu.org, blauwirbel@gmail.com, ohmura.kei@lab.ntt.co.jp, avi@redhat.com, vatsa@linux.vnet.ibm.com, pbonzini@redhat.com, psuriset@linux.vnet.ibm.com, stefanha@linux.vnet.ibm.com On Thu, Feb 10, 2011 at 10:54:01AM +0100, Anthony Liguori wrote: > On 02/10/2011 10:30 AM, Yoshiaki Tamura wrote: > >Currently FdMigrationState doesn't support read(), and this patch > >introduces it to get response from the other side. > > > >Signed-off-by: Yoshiaki Tamura > > Migration is unidirectional. Changing this is fundamental and not > something to be done lightly. Making it bi-directional might break libvirt's save/restore to file support which uses migration, passing a unidirectional FD for the file. It could also break libvirt's secure tunnelled migration support which is currently only expecting to have data sent in one direction on the socket. Daniel -- |: http://berrange.com -o- http://www.flickr.com/photos/dberrange/ :| |: http://libvirt.org -o- http://virt-manager.org :| |: http://autobuild.org -o- http://search.cpan.org/~danberr/ :| |: http://entangle-photo.org -o- http://live.gnome.org/gtk-vnc :|