CentOS virt - Nov 2009 - Unknown boot option `pciback.hide=(09:04.0)': ignoring

Good morning,

I need to use pciback.hide to hide a pci card because I want to pci
passthrough that card to a domU. My hardware neither supports Intel-Vt-d
nor AMD's IOMMU. Unfortunately this doesn't seem to work in Centos 54
anymore. I guess it doesn't work because it is not compiled into the
kernel, but as a module. I got the following error in dmesg and the pci
device is still listed in dom0 in lspci.

Bootdata ok (command line is ro root=/dev/dom0/root pciback.hide=(09:04.0))
Kernel command line: ro root=/dev/dom0/root pciback.hide=(09:04.0)
Unknown boot option `pciback.hide=(09:04.0)': ignoring

I also tried to update initrd to include the module but got the same
error message as above.

mkinitrd --with=pciback /boot/initrd-2.6.18-164.6.1.el5xen_pcipt
2.6.18-164.6.1.el5xen
title CentOS (2.6.18-164.6.1.el5xen PCI PT)
    root (hd1,0)
    kernel /xen.gz-2.6.18-164.6.1.el5
    module /vmlinuz-2.6.18-164.6.1.el5xen ro root=/dev/dom0/root
pciback.hide=(09:04.0)
    module /boot/initrd-2.6.18-164.6.1.el5xen_pcipt

Is there any option to use pciback.hide kernel parameter without
compiling a custom kernel?

Thanks in advance
G?nter Zimmermann

Hi,

after thinking about modules and modprobe.conf I added this line to
modprobe.conf:
options pciback hide=(09:04.0)

and rebuilt initrd.
mkinitrd -v --with=pciback /boot/initrd-2.6.18-164.6.1.el5xen_pcipt
2.6.18-164.6.1.el5xen

after a reboot I found this message in dmesg:
pciback 0000:09:04.0: seizing device

looks like it works, but I still have the device in lspci in dom0. 
Should it  be listed in lspci if pciback is working or not?

Regards
G?nter Zimmermann


G?nter Zimmermann schrieb:
> Good morning,
>
> I need to use pciback.hide to hide a pci card because I want to pci
> passthrough that card to a domU. My hardware neither supports Intel-Vt-d
> nor AMD's IOMMU. Unfortunately this doesn't seem to work in Centos
54
> anymore. I guess it doesn't work because it is not compiled into the
> kernel, but as a module. I got the following error in dmesg and the pci
> device is still listed in dom0 in lspci.
>
> Bootdata ok (command line is ro root=/dev/dom0/root pciback.hide=(09:04.0))
> Kernel command line: ro root=/dev/dom0/root pciback.hide=(09:04.0)
> Unknown boot option `pciback.hide=(09:04.0)': ignoring
>
> I also tried to update initrd to include the module but got the same
> error message as above.
>
> mkinitrd --with=pciback /boot/initrd-2.6.18-164.6.1.el5xen_pcipt
> 2.6.18-164.6.1.el5xen
> title CentOS (2.6.18-164.6.1.el5xen PCI PT)
>     root (hd1,0)
>     kernel /xen.gz-2.6.18-164.6.1.el5
>     module /vmlinuz-2.6.18-164.6.1.el5xen ro root=/dev/dom0/root
> pciback.hide=(09:04.0)
>     module /boot/initrd-2.6.18-164.6.1.el5xen_pcipt
>
> Is there any option to use pciback.hide kernel parameter without
> compiling a custom kernel?
>
> Thanks in advance
> G?nter Zimmermann
>
>