From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:43946) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1cF4rN-0001ge-6k for qemu-devel@nongnu.org; Thu, 08 Dec 2016 15:00:06 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1cF4rJ-0000oO-CM for qemu-devel@nongnu.org; Thu, 08 Dec 2016 15:00:05 -0500 Received: from mx1.redhat.com ([209.132.183.28]:58926) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1cF4rJ-0000o1-7j for qemu-devel@nongnu.org; Thu, 08 Dec 2016 15:00:01 -0500 Date: Thu, 8 Dec 2016 19:59:55 +0000 From: "Dr. David Alan Gilbert" Message-ID: <20161208195955.GG2054@work-vm> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] migration: Introduce a new "--only-migratable" option List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Ashijeet Acharya Cc: QEMU Developers * Ashijeet Acharya (ashijeetacharya@gmail.com) wrote: > Hi Dave, > > I have added the compatibility of this option for both command line > and hotplug via qmp and hmp. Although, please confirm that making use > of "device_add" is the only way of hotplugging devices into a QEMU > instance. Hmm; there's obsolete commands like usb_add and netdev_add as well. > With this sorted out, there is one special case left where the device > dynamically declares itself 'unmigratable' via migrate_add_blocker. I > have a query regarding that which is, what is the preferred action in > this scenario? Should I unmount the device or restrict the device from > becoming unmigratable in the first place. > For example, restrict 9pfs from mounting the filesystem (which you > explained previously). > > Or is there a completely different solution in your mind? My preferred solution is to stop the device getting into the unmigratable state; so whatever function tries to set it should fail (nicely) and give an error - e.g the 9pfs should refuse to mount. I'm not sure how hard that is. Dave > Thanks > Ashijeet -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK