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 Günter Zimmermann Günter 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 > Günter Zimmermann > >