Bug 248834

Description of problem:
Upgraded to kernel-xen-2.6.20-2925.13.fc7 (from updates-testing) and tried to
create a new Xen guest with virt-install. I got the following error message:

kernel BUG at net/core/net-sysfs.c:429!
invalid opcode: 0000 [1] SMP

The full syslog is attached, but here's the interesting part:

xen kernel: kobject_add failed for brport (-13)
xen kernel: Call Trace:
xen kernel:  [<ffffffff8031dce6>] kobject_add+0x163/0x18e
xen kernel:  [<ffffffff8823a493>] :bridge:br_add_if+0x1d2/0x2d8
xen kernel:  [<ffffffff8823ab7d>] :bridge:add_del_if+0x41/0x5e
xen kernel:  [<ffffffff8823b203>] :bridge:br_dev_ioctl+0x669/0x6a2

( with some SELinux errors, see bug 245274 comment 13 )

MySQL was running on the server when I got that error message, and it continued
running fine despite this error. However, I was no longer able to ssh into the
server. I tried rebooting the server remotely with 'shutdown -r now', but for
some unknown reason the server didn't shut down properly and I had to visit our
server room to power cycle the server. 

The previous version (2.6.20-2925.11) didn't crash like this.

This is on Dell Poweredge 2900, with two integrated NICs and a four port D-Link
DFE-580TX, which is hidden from Domain0 with
pciback.hide=(0c:04.0)(0c:05.0)(0c:06.0)(0c:07.0).

Version-Release number of selected component (if applicable):
bridge-utils-1.1-2
kernel-xen-2.6.20-2925.13.fc7
selinux-policy-targeted-2.6.4-28.fc7
selinux-policy-2.6.4-28.fc7

How reproducible:
Haven't tried to reproduce the problem yet

Steps to Reproduce:
1. boot with kernel-xen-2.6.20-2925.13
2. run virt-install to create a new guest image:
[root@xen ~]# virt-install
Would you like a fully virtualized guest (yes or no)?  This will allow you to
run unmodified operating systems. no
 What is the name of your virtual machine? gw
 How much RAM should be allocated (in megabytes)? 384
 What would you like to use as the disk (path)? /var/lib/xen/images/gw
 Would you like to enable graphics support? (yes or no) no
 What is the install location? ftp://192.168.0.160/documents/fc7/x86_64/os/
3. Crash!
  
Actual results:
Kernel crash

Expected results:
New Xen virtual machine created successfully