From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ingo Molnar Subject: Re: [PATCH 2/2] kvm tools: Add virtio-9p Date: Tue, 17 May 2011 21:20:52 +0200 Message-ID: <20110517192052.GD29574@elte.hu> References: <1305657337-2584-1-git-send-email-levinsasha928@gmail.com> <1305657337-2584-2-git-send-email-levinsasha928@gmail.com> <20110517184023.GC16689@elte.hu> <1305659307.12150.37.camel@sasha> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: penberg@kernel.org, asias.hejun@gmail.com, prasadjoshi124@gmail.com, gorcunov@gmail.com, kvm@vger.kernel.org To: Sasha Levin Return-path: Received: from mx2.mail.elte.hu ([157.181.151.9]:33199 "EHLO mx2.mail.elte.hu" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756439Ab1EQTU6 (ORCPT ); Tue, 17 May 2011 15:20:58 -0400 Content-Disposition: inline In-Reply-To: <1305659307.12150.37.camel@sasha> Sender: kvm-owner@vger.kernel.org List-ID: * Sasha Levin wrote: > On Tue, 2011-05-17 at 20:40 +0200, Ingo Molnar wrote: > > * Sasha Levin wrote: > > > > > 3. Within the guest, mount the fs: > > > mount -t 9p -otrans=virtio kvm_9p -oversion=9p2000 > > > This will mount the 9p server to local_dir. > > > > Really cool! > > Thanks! > > > is root-9p possible? I.e. ideally i'd like to have no image at all - just a > > guest kernel and a directory hierarchy for the guest filesystem. > > >From what I can tell, not currently. > > 'kvm_9p' isn't created as a device under /dev, it's just a name used > internally by 9pnet_virtio (and located under sysfs). > > I couldn't figure out which params the kernel would expect to boot using > 9p over virtio (theres no device name to begin with). > > I've also couldn't find anything that suggested it's possible to boot > using virtio-9p as rootfs. This needs guest kernel support, in form of a small amount of 9p specific mounting glue code that the guest kernel will run if either a .config option is set or a boot commandline is specified. Such a thing already exists for another networked filesystem: NFS, so i would suggest looking at the CONFIG_ROOT_NFS=y glue in Linux, i think 9p mounting support would be welcome! Thanks, Ingo