Fedora xen - Jun 2008 - PCI passthrough

I have an F8 dom0 (which could become a CentOS 5.2 dom0 if that would
make anything easier) I''d like an F9 domU to have access to a PCI DVB
tuner for a mythtv backend.

I understand that I need to add "pciback.hide=(XX:YY.Z)" and possibly
"pciback.permissive" to grub.conf for the dom0

How should I add the details of the corresponding "pci =
[''XX:YY.Z'']"
to the domU config?

I''ve looked in the documentation of the XML format at
http://libvirt.org/formatdomain.html
but can''t see relevant tags.

2008/6/27 Andy Burns <fedora.lists@burns.me.uk>:
> I have an F8 dom0 (which could become a CentOS 5.2 dom0 if that would
> make anything easier) I''d like an F9 domU to have access to a PCI
DVB
> tuner for a mythtv backend.
OK, I''ve re-read some old threads that I''d forgotten about,
and
realised F9 hasn''t got pci passthrough support.

So to change plan, will either F8 or CentOS5.2 domU''s support pci
passthrough, on top of either F8 or CentOS5.2 dom0? Since this is a
home machine I''m inclined to stay on Fedora rather than shift it to
CentOS is possible, otherwise I don''t get to play with new features.

I really hope Xen options are less restricted again for F10, I don''t
intend this to sound like like a whine, I know people are working hard
on paravirt_ops, it''s just that losing options is always hard to
swallow.

2008/6/28 Andy Burns <fedora.lists@burns.me.uk>:
> to change plan, will either F8 or CentOS5.2 domU''s support pci
> passthrough, on top of either F8 or CentOS5.2 dom0?
I''ve kept F8 as dom0 and now using CentOS5.2 as domU

I''ve added pciback.hide=(08.01.0) to grub.conf for dom0

but it seems that pciback options are not understood at boot time (due
to it being a module?)

I''m aware I may be able to handle preventing dom0 handling the device
better in the long term with /etc/modprobe.conf, but for now I''m
running a little script in dom0

rmmod saa7134
modprobe pciback
SLOT=0000:08:01.0
echo -n $SLOT > /sys/bus/pci/drivers/pciback/new_slot
echo -n $SLOT > /sys/bus/pci/drivers/pciback/bind

I''ve created a new domU using the centosplus kernel to get extra V4L
drivers with the following /etc/xen/ style config file

memory = 1024
name = "mythbe"
vif = [ ''mac=00:16:3E:76:E8:92, bridge=eth0'' ]
disk = [ ''phy:/dev/vgr1/lvmythroot,xvda,w'' ]
pci = [''08:01.0'']
bootloader = "/usr/bin/pygrub"
vcpus = 1
on_reboot = ''restart''
on_crash = ''restart''

The domU starts OK, and the pci device is present

# lspci -v
00:00.0 Multimedia controller: Philips Semiconductors SAA7130 Video
Broadcast Decoder (rev 01)
        Subsystem: Compro Technology, Inc. Videomate DVB-T200
        Flags: bus master, medium devsel, latency 64, IRQ 17
        Memory at febffc00 (32-bit, non-prefetchable) [size=1K]
        Capabilities: [40] Power Management version 1

I assume it is normal that the bus/slot/function numbers are not the
same in domU as in dom0?

I can load the driver for the card in the domU

# lsmod | grep saa
saa7134               159017  0
video_buf              59717  1 saa7134
compat_ioctl32         41793  1 saa7134
ir_kbd_i2c             42961  1 saa7134
i2c_core               56129  2 saa7134,ir_kbd_i2c
ir_common              63173  2 saa7134,ir_kbd_i2c
videodev               58049  1 saa7134
v4l1_compat            44613  2 saa7134,videodev
v4l2_common            57153  3 saa7134,compat_ioctl32,videodev

However, I am seeing an error in dmesg of domU

# dmesg | grep saa
saa7130/34: v4l2 driver version 0.2.14 loaded
saa7130[0]: found at 0000:00:00.0, rev: 1, irq: 17, latency: 64, mmio:
0xfebffc00
saa7130[0]: subsystem: 185b:c901, board: Compro Videomate DVB-T200
[card=71,autodetected]
saa7130[0]: can''t ioremap() MMIO memory
saa7134: probe of 0000:00:00.0 failed with error -5

Any suggestions?