From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:60057) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1advTk-0003n7-Jg for qemu-devel@nongnu.org; Thu, 10 Mar 2016 02:57:53 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1advTg-0000Z4-Me for qemu-devel@nongnu.org; Thu, 10 Mar 2016 02:57:52 -0500 Received: from mx1.redhat.com ([209.132.183.28]:57400) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1advTg-0000Yx-Gq for qemu-devel@nongnu.org; Thu, 10 Mar 2016 02:57:48 -0500 Date: Thu, 10 Mar 2016 13:27:28 +0530 From: Amit Shah Message-ID: <20160310075728.GB4678@grmbl.mre> References: <1457001868-15949-1-git-send-email-liang.z.li@intel.com> <20160308111343.GM15443@grmbl.mre> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Subject: Re: [Qemu-devel] [RFC qemu 0/4] A PV solution for live migration optimization List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Li, Liang Z" Cc: "ehabkost@redhat.com" , "kvm@vger.kernel.org" , "mst@redhat.com" , "quintela@redhat.com" , "linux-kernel@vger.kernel.org" , "qemu-devel@nongnu.org" , "linux-mm@kvack.org" , "pbonzini@redhat.com" , "akpm@linux-foundation.org" , "virtualization@lists.linux-foundation.org" , "dgilbert@redhat.com" , "rth@twiddle.net" On (Thu) 10 Mar 2016 [07:44:19], Li, Liang Z wrote: > > Hi Amit, > > Could provide more information on how to use virtio-serial to exchange data? Thread , Wiki or code are all OK. > I have not find some useful information yet. See this commit in the Linux sources: 108fc82596e3b66b819df9d28c1ebbc9ab5de14c that adds a way to send guest trace data over to the host. I think that's the most relevant to your use-case. However, you'll have to add an in-kernel user of virtio-serial (like the virtio-console code -- the code that deals with tty and hvc currently). There's no other non-tty user right now, and this is the right kind of use-case to add one for! For many other (userspace) use-cases, see the qemu-guest-agent in the qemu sources. The API is documented in the wiki: http://www.linux-kvm.org/page/Virtio-serial_API and the feature pages have some information that may help as well: https://fedoraproject.org/wiki/Features/VirtioSerial There are some links in here too: http://log.amitshah.net/2010/09/communication-between-guests-and-hosts/ Hope this helps. Amit