From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from [140.186.70.92] (port=39207 helo=eggs.gnu.org) by lists.gnu.org with esmtp (Exim 4.43) id 1PhRG2-0006Au-GY for qemu-devel@nongnu.org; Mon, 24 Jan 2011 13:35:19 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1PhRG1-000099-99 for qemu-devel@nongnu.org; Mon, 24 Jan 2011 13:35:18 -0500 Received: from mail-yx0-f173.google.com ([209.85.213.173]:53460) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1PhRG1-000093-3h for qemu-devel@nongnu.org; Mon, 24 Jan 2011 13:35:17 -0500 Received: by yxl31 with SMTP id 31so1602101yxl.4 for ; Mon, 24 Jan 2011 10:35:16 -0800 (PST) Message-ID: <4D3DC662.4040305@landley.net> Date: Mon, 24 Jan 2011 12:35:14 -0600 From: Rob Landley MIME-Version: 1.0 Subject: Re: [Qemu-devel] Playing with virtfs. References: <4D3C827A.8080207@landley.net> <87pqrmnuqk.fsf@linux.vnet.ibm.com> In-Reply-To: <87pqrmnuqk.fsf@linux.vnet.ibm.com> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit List-Id: qemu-devel.nongnu.org List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: "Aneesh Kumar K. V" Cc: qemu-devel@nongnu.org On 01/24/2011 10:15 AM, Aneesh Kumar K. V wrote: > On Sun, 23 Jan 2011 13:33:14 -0600, Rob Landley wrote: >> Using yesterday's -git, following the instructions in >> http://wiki.qemu.org/Documentation/9psetup (which is missing a kernel >> symbol, you need to add CONFIG_VIRTIO_PCI to your kernel too), I managed >> to mount a read-only virtfs filesystem, adding this to the >> qemu-system-x86_64 command line: > > With top of the kernel tree 52cfd503ad7176d23a5dd7af3981744feb60622f > I am able to build the kernel without CONFIG_VIRTIO_PCI. What is the > exact error you are finding ? It wasn't a runtime error, it's that some of the config symbols the instructions told me to switch on were hidden. CONFIG_NET_9P_VIRTIO depends on CONFIG_VIRTIO which is selected by CONFIG_VIRTIO_PCI. If CONFIG_VIRTIO isn't forced on by something, you can't select CONFIG_NET_9P_VIRTIO. >> >> -virtfs >> local,security_model=passthrough,mount_tag=kvm,path=/home/landley/9ptest >> >> And then in the emulated Linux: >> >> root@kvm:~# mount -t 9p -o trans=virtio,version=9p2000.L kvm woot >> root@kvm:~# ls -l woot >> total 80 >> -rw-r--r-- 1 1000 1000 77874 Jan 22 23:33 config-linux >> root@kvm:~# cd woot >> root@kvm:~/woot# touch fred >> touch: setting times of `fred': No such file or directory >> root@kvm:~/woot# >> >> I.E. It seems to work fine read only, but changes are discarded. >> >> Am I doing something wrong, or is this expected? (If so, when is write >> support likely to go in?) >> > > Are you running qemu as root ? Nope, I try to avoid doing that where possible. > Using passthrough security model require > the ability to change the ownership of the file. Otherwise you can use > security=none, but the credentials with which files are created will > not be correct. Yup, that was it. I note that security=mapped behaves like security=passthrough. (Which is a pity, because it would have been the first legitimate use for extended attributes I've seen since I stopped using OS/2.) > -aneesh It works! Thanks. Rob