2010/12/14 Erik Brakkee<erik@xxxxxxxxxxx>:
Daniel P. Berrange wrote:
On Tue, Dec 14, 2010 at 12:55:04PM +0100, Kenni Lund wrote:
2010/12/14 Erik Brakkee<erik@xxxxxxxxxxx>:
From: Kenni Lund<kenni@xxxxxxx>
2010/12/14 Erik Brakkee<erik@xxxxxxxxxxx>:
From: Kenni Lund<kenni@xxxxxxx>
Does this mean I have a chance now that PCI passthrough of my
WinTV
PVR-500
might work now?
Passthrough of a PVR-500 has been working for a long time. I've
been
running with passthrough of a PVR-500 in my HTPC, since
November/December 2009...so it should work with any recent
kernel
and
any recent version of qemu-kvm you can find today - No patching
needed. The only issue I had with the PVR-500 card, was when *I*
didn't free up the shared interrupts...once I fixed that, it
"just
worked".
How did you free up those shared interrupts then? I tried
different
slots
but always get conflicts with the USB irqs.
I did an unbind of the conflicting device (eg. disabled it). I
moved
the PVR-500 card around in the different slots and once I got a
conflict with the integrated sound card, I left the PVR-500
card in
that slot (it's a headless machine, so no need for sound) and
configured unbind of the sound card at boot time. On my old
system I
think it was conflicting with one of the USB controllers as well,
but
it didn't really matter, as I only lost a few of the ports on the
back
of the computer for that particular USB controller - I still had
plenty of USB ports left and if I really needed more ports, I
could
just plug in an extra USB PCI card.
My /etc/rc.local boot script looks like the following today:
--
#Remove HDA conflicting with ivtv1
echo "0000:00:1b.0"> /sys/bus/pci/drivers/HDA\ Intel/unbind
# ivtv0
echo "4444 0016"> /sys/bus/pci/drivers/pci-stub/new_id
echo "0000:04:08.0"> /sys/bus/pci/drivers/ivtv/unbind
echo "0000:04:08.0"> /sys/bus/pci/drivers/pci-stub/bind
echo "4444 0016"> /sys/bus/pci/drivers/pci-stub/remove_id
# ivtv1
echo "4444 0016"> /sys/bus/pci/drivers/pci-stub/new_id
echo "0000:04:09.0"> /sys/bus/pci/drivers/ivtv/unbind
echo "0000:04:09.0"> /sys/bus/pci/drivers/pci-stub/bind
echo "4444 0016"> /sys/bus/pci/drivers/pci-stub/remove_id
I did not try unbinding the usb device so I can also try that.
I don'.t understand what is happening with the 4444 0016. I
configured
the
pci card in kvm and I believe kvm does the binding to pci-stub in
recent
versions. Where is the 4444 0016%oming from?
Okay, qemu-kvm might do it today, I don't know - I haven't changed
that script for the past year. But are you sure that it's not
libvirt/virsh/virt-manager which does that for you?
If you use the managed="yes" attribute on the<hostdev> in libvirt
XML, then libvirt will automatically do the pcistub bind/unbind,
followed by a device reset at guest startup& the reverse at
shutdown.
If you have conflicting devices on the bus though, libvirt won't
attempt to unbind them, unless you had also explicitly assigned all
those conflicting devices to the same guest.
Daniel
I definitely have to try again (right now having some stability
problems
on
the server that I am debugging).
The shared IRQs are as follows:
16: 0 0 0 0
0 0
0 0 IO-APIC-fasteoi uhci_hcd:usb3
18: 252995 0 0 0
0 0
0 0 IO-APIC-fasteoi ehci_hcd:usb1, uhci_hcd:usb8,
ivtv0
19: 58281 0 0 0
0 0
0 0 IO-APIC-fasteoi ata_piix, ata_piix,
uhci_hcd:usb5,
uhci_hcd:usb7, ivtv1
21: 0 0 0 0
0 0
0 0 IO-APIC-fasteoi uhci_hcd:usb4
23: 713 6906 0 76919
0 0
0 0 IO-APIC-fasteoi ehci_hcd:usb2, uhci_hcd:usb6
So I have IRQ sharing with usb1, usb8, usb5, usb7.
Uff....and your ata HDD controller. I guess i was much luckier than
you are, my ivtv0 didn't conflict at all and ivtv1 only conflicted
with USB.
I have also read that
ehci refers to USB 2.0 and uhci to USB 1.1 is that correct? Anyway,
how
would I now identify the USB PCI devices that I would need to
unbind to
get
rid of the sharing with the USB ports?
Play around with:
lspci -v
lspci -n
lsusb -v
lsusb -t
You can also just start by unbinding the first one and take note when
you hit the right ones...once you unbind one, it will disappear from
cat /proc/interrupts. When you're down to having only ivtv0 on one
interrupt and only ivtv1 on another interrupt, then you're ready to
bind with pci-stub and boot your guest.
It also doesn't really matter in
which slot I put the PVR-500 card because both cards share IRQs
with USB
in
all cases.
You also have your conflicting ata controller to take into
consideration. I don't remember if "ata_piix" and "ata_piix" is IDE
only, if it is, you might not even use it. Otherwise it might be
easier for you to run qemu-kvm git with the new patches for shared
interrupts...it really depends on your setup.
I have also used an add on USB PCI card but still got these
conflicts. I
was
considering to get a PCIe USB card instead to try out in the hope that
that
would use different IRQs. Is that a realistic expectation? That way, I
could
disable all on-board USB (in the BIOS even) and use the add-on USB
only.
Most likely, the PCIe USB 3.0 card I bought supported MSI-X, so it got
its own unique IRQs which wasn't shared with anything.
