Red Hat Bugzilla – Bug 500568
kernel-xen should *not* include pci-stub driver
Last modified: 2009-09-02 04:56:01 EDT
Description of problem:
The latest kernel-xen has the newly backported pci-stub driver built-in to the kernel by default.
This causes a problem in handling of PCI passthrough to guest VMs, because libvirt sees that pci-stub is present and uses that. XenD in RHEL-5, however, *requires* that pciback is used and cannot work with pci-stub. It is not even possible to workaround this by blacklisting the pci-stub because it was compiled into the kernel, not built as a module.
We need to turn off pci-stub for kernel-xen builds, and only have it in bare-metal builds for use with KVM
Version-Release number of selected component (if applicable):
Linux rhel5xen 2.6.18-146.el5xen #1 SMP Mon May 11 19:08:09 EDT 2009 i686 athlon i386 GNU/Linux
Steps to Reproduce:
1. Boot kernel-xen
2. ls /sys/bus/pci/drivers
pci-stub is present
pci-stub is not present, and also not built as a module
Created attachment 344191 [details]
Remove pci-stub driver from -xen kernels
You can download this test kernel from http://people.redhat.com/dzickus/el5
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