From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mailman by lists.gnu.org with tmda-scanned (Exim 4.43) id 1Me8mi-0003Pi-HS for qemu-devel@nongnu.org; Thu, 20 Aug 2009 10:38:36 -0400 Received: from exim by lists.gnu.org with spam-scanned (Exim 4.43) id 1Me8md-0003NH-0T for qemu-devel@nongnu.org; Thu, 20 Aug 2009 10:38:35 -0400 Received: from [199.232.76.173] (port=40096 helo=monty-python.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1Me8mc-0003N6-TO for qemu-devel@nongnu.org; Thu, 20 Aug 2009 10:38:30 -0400 Received: from mx1.redhat.com ([209.132.183.28]:1528) by monty-python.gnu.org with esmtps (TLS-1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.60) (envelope-from ) id 1Me8mb-0001TS-UN for qemu-devel@nongnu.org; Thu, 20 Aug 2009 10:38:30 -0400 Date: Thu, 20 Aug 2009 20:08:02 +0530 From: Amit Shah Subject: Re: [Qemu-devel] Re: virtio-serial: An interface for host-guest communication Message-ID: <20090820143802.GA20265@amit-x200.redhat.com> References: <4A7FECCA.8080804@redhat.com> <4A801A7B.1020208@codemonkey.ws> <4A80287C.7050400@redhat.com> <4A802CA7.9020701@codemonkey.ws> <4A803E07.7080407@redhat.com> <4A8051F3.7040400@codemonkey.ws> <20090814081518.GA7418@amit-x200.redhat.com> <4A8566B8.8030808@codemonkey.ws> <20090820134241.GA19395@amit-x200.redhat.com> <20090820142509.GD27710@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20090820142509.GD27710@redhat.com> List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Daniel P. Berrange" Cc: Rusty Russell , Gerd Hoffmann , qemu-devel@nongnu.org, kvm@vger.kernel.org, virtualization@lists.linux-foundation.org On (Thu) Aug 20 2009 [15:25:09], Daniel P. Berrange wrote: > On Thu, Aug 20, 2009 at 07:12:41PM +0530, Amit Shah wrote: > > > > I've now seen some more code here and to me it looks like virtioconsole > > is not used on any of the guests that qemu supports. The virtio_console > > kernel module only works with lguest and s390 currently. There is one > > feature and some config values supported by the kernel module but not in > > qemu. > > > > So it looks as if we have virtio-console merged but no one uses it. Is > > this right? > > Nope. Grab a Fedora 11 live CD, and boot with > > # qemu-kvm -virtioconsole stdio -cdrom Fedora-11-i686-Live.iso -m 500 > > Once it completes booting & logs into gnome, open a terminal and run > as root > > agetty /dev/hvc0 9600 vt100 > > You'll get a login prompt on the host machine now. > > What appears to not be working, is early kernel boot messages. eg, I > ought to be able todo Oh; ok. So the console device is exposed only in the userspace; it's not used for the early boot messages and not registered early-on. That's only done for lguest and s390. > # qemu-kvm -virtioconsole stdio -kernel vmlinuz -initrd initrd.img \ > -append "console=hvc0" -m 500 > > and see the kernel boot messages, but this doesn't work with Fedora > kernels at least. Not tried upstream, or looked to see if this is just > an oversight in the Kconfig use for Fedora kernels. Thanks, Amit