Miscellany

Red Hat nash version 5.1.19.6 starting
Mounting proc filesystem
Mounting sysfs filesystem
Creating /dev
Creating initial device nodes
Setting up hotplug.
Creating block device nodes.
Loading ehci-hcd.ko module
Loading ohci-hcd.ko module
Loading uhci-hcd.ko module
USB Universal Host Controller Interface driver v3.0
Loading jbd.ko module
Loading ext3.ko module
Loading raid1.ko module
md: raid1 personality registered for level 1
Loading xenblk.ko module
Registering block device major 202
 xvda: xvda1 xvda2 xvda3 xvda4 < xvda5 >
 xvdb: xvdb1 xvdb2 xvdb3 xvdb4 < xvdb5 >
 xvdc: xvdc1
kobject_add failed for xvda with -EEXIST, don't try to register things with the same name in the same directory.

Call Trace:
 [<ffffffff803404ea>] kobject_add+0x170/0x19b
 [<ffffffff8025cfd5>] exact_lock+0x0/0x14
 [<ffffffff8029b92c>] keventd_create_kthread+0x0/0xc4
 [<ffffffff802fb4e2>] register_disk+0x43/0x190
 [<ffffffff8029b92c>] keventd_create_kthread+0x0/0xc4
 [<ffffffff80336c3a>] add_disk+0x34/0x3d
 [<ffffffff88084ec9>] :xenblk:backend_changed+0x110/0x193
 [<ffffffff803b32fa>] xenbus_read_driver_state+0x26/0x3b
 [<ffffffff803b4bdb>] xenwatch_thread+0x0/0x135
 [<ffffffff803b402d>] xenwatch_handle_callback+0x15/0x48
 [<ffffffff803b4cf7>] xenwatch_thread+0x11c/0x135
 [<ffffffff8029bb44>] autoremove_wake_function+0x0/0x2e
 [<ffffffff8029b92c>] keventd_create_kthread+0x0/0xc4
 [<ffffffff80233bcd>] kthread+0xfe/0x132
 [<ffffffff80260b2c>] child_rip+0xa/0x12
 [<ffffffff8029b92c>] keventd_create_kthread+0x0/0xc4
 [<ffffffff80233acf>] kthread+0x0/0x132
 [<ffffffff80260b22>] child_rip+0x0/0x12

Unable to handle kernel NULL pointer dereference at 0000000000000010 RIP: 
 [<ffffffff802fe512>] create_dir+0x11/0x1cf
PGD 7f1c9067 PUD 7f1ca067 PMD 0 
Oops: 0000 [1] SMP 
last sysfs file: /block/ram0/dev
CPU 1 
Modules linked in: xenblk raid1 ext3 jbd uhci_hcd ohci_hcd ehci_hcd
Pid: 9, comm: xenwatch Not tainted 2.6.18-164.el5xen #1
RIP: e030:[<ffffffff802fe512>]  [<ffffffff802fe512>] create_dir+0x11/0x1cf
RSP: e02b:ffff880000fbfda0  EFLAGS: 00010282
RAX: ffff88007f31b870 RBX: ffff88007f3cd4f0 RCX: ffff880000fbfdd8
RDX: ffff88007f3cd4f8 RSI: 0000000000000000 RDI: ffff88007f3cd4f0
RBP: ffff88007f3cd4f0 R08: 0000000000000001 R09: ffff88000114c000
R10: ffffffff8029b92c R11: ffff880000fbfbb0 R12: ffff88007f3cd4f0
R13: ffff880000fbfdd8 R14: 0000000000000000 R15: ffff88007f31b870
FS:  0000000000000000(0000) GS:ffffffff805ca080(0000) knlGS:0000000000000000
CS:  e033 DS: 0000 ES: 0000