Re: [Xen-users] PCI passthrough to Windows XP

[Ian Campbell <Ian.Campbell@xxxxxxxxxx>]

On Fri, 2012-11-09 at 10:44 +0000, Daniel Shub wrote:
> > > > > #grep hide /boot/grub/grub.cfg
> > > > >
> > > > > Returns two lines of
> > > > >
> > > > > multiboot /boot/xen-4.0-amd64.gz placeholder
> > > > > xen-pciback.hide(05:00.0)(06:04.0)
> > > Shouldn't this line be on the kernel line in grub and not the xen.gz
> > line?
> > > In my understanding it is the xen-pciback module in the linux kernel
> > who does the hiding.
> > 
> > I missed this -- you are absolutely correct that this option should be
> > passed to the dom0 kernel.
> > 
> > If using update-grub with the standard grub.d snippets hten it should
> > be added /etc/default/grub in the GRUB_CMDLINE_LINUX_XEN_REPLACE or
> > GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT. Or
> > GRUB_CMDLINE_LINUX_DEFAULT/GRUB_CMDLINE_LINUX would work (and be
> > harmless, I think, when booting native).
> > 
> > GRUB_CMDLINE_XEN_DEFAULT and GRUB_CMDLINE_LINUX_DEFAULT are both the
> > wrong place to add this new option.
> > 
> I am confused. At first you say GRUB_CMDLINE_LINUX_DEFAULT "would work
> (and be harmless)", but then say it is "the wrong place to add this
> new option".

Sorry. cut-n-paste the wrong thing.

Good:
GRUB_CMDLINE_LINUX_XEN_REPLACE
GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT
GRUB_CMDLINE_LINUX
GRUB_CMDLINE_LINUX_DEFAULT

Bad:
GRUB_CMDLINE_XEN
GRUB_CMDLINE_XEN_DEFAULT

> Adding to GRUB_CMDLINE_LINUX_XEN_REPLACE or 
> GRUB_CMDLINE_LINUX_XEN_REPLACE_DEFAULT doesn't work (nothing gets added to 
> /boot/grub/grub.cfg). Adding to GRUB_CMDLINE_LINUX results in 
> 
> #grep hide /boot/grub/grub.cfg
>       module  /boot/vmlinuz-2.6.32-5-xen-amd64 placeholder 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro 
> xen-pciback.hide(05:00.0)(06:04.0) quiet
>       module  /boot/vmlinuz-2.6.32-5-xen-amd64 placeholder 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro single 
> xen-pciback.hide(05:00.0)(06:04.0)
>       linux   /boot/vmlinuz-2.6.32-5-xen-amd64 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro 
> xen-pciback.hide(05:00.0)(06:04.0) quiet
>       linux   /boot/vmlinuz-2.6.32-5-xen-amd64 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro single 
> xen-pciback.hide(05:00.0)(06:04.0)
>       linux   /boot/vmlinuz-2.6.32-5-amd64 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro 
> xen-pciback.hide(05:00.0)(06:04.0) quiet
>       linux   /boot/vmlinuz-2.6.32-5-amd64 
> root=UUID=2c69309c-05ce-4e2d-b9f9-d651e65342ae ro single 
> xen-pciback.hide(05:00.0)(06:04.0)
> 
> but I am still unable to use the pci passthrough.

You seem to still be missing the "=" after the xen-pciback.hide.

> At this point I am still not sure that the Debain Squeeze kernel
> supports xen-pciback or if I need to load a module. I also do not know
> if I should be using xen-pciback or just pciback (I have been trying
> everything with both).

I don't have a Squeeze box handy to check.

"find /lib/modules/$(uname -r) -name \*pciback\*" will find you the
module (and therefore its name) if it exists.

"grep PCIBACK /boot/config-$(uname -r)" should give you a =y or =m
answer if it is static or modular.

You can probably aloso find some files with the name under /sys
somewhere.

You could also just try modprobe pciback ; modprobe xen-pciback and see
what it loads.

Ian.


_______________________________________________
Xen-users mailing list
Xen-users@xxxxxxxxxxxxx
http://lists.xen.org/xen-users