Re: [Qemu-devel] 9pfs troubles (was Re: [PATCH 1/4] hw/9pfs: fix error handing in local_ioc_getversion())

[Michael S. Tsirkin]

On Tue, Feb 04, 2014 at 12:51:25PM +0530, Aneesh Kumar K.V wrote:
> "Michael S. Tsirkin" <address@hidden> writes:
> 
> > On Mon, Feb 03, 2014 at 03:05:10PM +0530, Aneesh Kumar K.V wrote:
> >> "Michael S. Tsirkin" <address@hidden> writes:
> >> 
> >> > Haven't used 9pfs in a while.
> >> > I thought these patches are a good time to play with it some more.
> >> > I have encountered two issues.
> >> >
> >> > What I'm doing:
> >> > host: qemu a75143eda2ddf581b51e96c000974bcdfe2cbd10.
> >> >
> >> > /scm/qemu/x86_64-softmmu/qemu-system-x86_64 -enable-kvm -m 1g -cpu kvm64
> >> > -smp 2  f20-x64.qcow2  -netdev user,id=foo -redir tcp:8022::22 -device
> >> > virtio-net,netdev=foo  -serial stdio -fsdev
> >> > local,security_model=none,id=fsdev0,path=/lib/modules/ -device
> >> > virtio-9p-pci,id=fs0,fsdev=fsdev0,mount_tag=libmodulesshare -fsdev
> >> > local,security_model=none,id=fsdev1,path=/boot -device
> >> > virtio-9p-pci,id=fs1,fsdev=fsdev0,mount_tag=bootshare -no-reboot
> >> > -snapshot
> >> >
> >> > guest: Fedora 20
> >> >
> >> > added this in /etc/fstab:
> >> >
> >> > bootshare       /share/boot     9p      trans=virtio,version=9p2000.L 0 0
> >> > libmodulesshare /share/lib/modules      9p trans=virtio,version=9p2000.L 
> >> > 0 0
> >> >
> >> >
> >> > I have encountered two issues:
> >> >
> >> > 1. mount failure on boot
> >> > If I try to mount on boot through fstab, I get:
> >> > [    2.270157] 9pnet: Could not find request transport: virtio
> >> > [    2.270158] 9pnet: Could not find request transport: virtio
> >> 
> >> 
> >> Missing 9pnet_virtio.ko module ? 
> >
> > Maybe it's loaded too late. But when I get to plymouth prompt
> > it's loaded fine.

Any idea about this one? Do you have guests with 9pfs
and virtio as modules and 9pfs mounted from /etc/fstab?

> >> >
> >> > If I then re-try mount, it succeeds immediately!
> >> >
> >> > Some kind of dependency issue?
> >> >
> >> > 2. files immediately in the mounted directory aren't visible on the
> >> > guest under /share/boot.
> >> > For example, files under /boot on host are not visible
> >> > on guest, files under child directories seem visible.
> >> 
> >> 
> >> can you share more details on this ? /boot permissions. ls -al output on
> >> host etc.
> >> 
> >> -aneesh
> >
> > for /boot:
> > dr-xr-xr-x. 7 root root 12288 Feb  2 23:41 /boot/
> >
> > $ ls -la
> > total 739740
> > dr-xr-xr-x.  7 root root    12288 Feb  2 23:41 .
> > dr-xr-xr-x. 22 root root     4096 Feb  2 19:16 ..
> > -rw-r--r--.  1 root root   138741 Dec 23 19:19 config-3.12.6-200.fc19.i686
> > -rw-r--r--.  1 root root   138724 Jan 10 18:06 config-3.12.7-200.fc19.i686
> > -rw-r--r--.  1 root root   138724 Jan 16 06:43
> > config-3.12.8-200.fc19.i686
> 
> 
> Related to SELinux errors ? can you double check you don't selinux
> errors.

No, I didn't see any selinux errors.
Also was able to stat and read files as a regular user.

> Can you also share the file listing on the guest ?

Interestingly, the problem seems to be partially gone.
Not sure what did I change
What I do still see now is this:

Host:
$ ls -l /boot/initramfs-3.11.0-rc5-mst.img
-rw-------. 1 root root 7659204 Aug 18 13:21 /boot/initramfs-3.11.0-rc5-mst.img
Guest:
ls -l /share/initramfs-3.11.0-rc5-mst.img 
ls: cannot access /share/initramfs-3.11.0-rc5-mst.img: Permission denied




>  Also are you able to
> reproduce this when running qemu as root user ?
> 
> -aneesh