Description of problem:
dmesg does show this kernel error after booting:

stack backtrace:
 [<c04051ed>] show_trace_log_lvl+0x58/0x16a
 [<c04057fa>] show_trace+0xd/0x10
 [<c0405913>] dump_stack+0x19/0x1b
 [<c043b10f>] print_circular_bug_tail+0x59/0x64
 [<c043b898>] __lock_acquire+0x77e/0x90d
 [<c043bf98>] lock_acquire+0x4b/0x6b
 [<c06135f3>] __mutex_lock_slowpath+0xbc/0x20a
 [<c0613762>] mutex_lock+0x21/0x24
 [<c0479c8a>] bd_claim_by_disk+0x5f/0x169
 [<c05a16ca>] bind_rdev_to_array+0x20a/0x228
 [<c05a3571>] autorun_devices+0x1c8/0x29d
 [<c05a5dea>] md_ioctl+0x104/0x1540
 [<c04df7e0>] blkdev_driver_ioctl+0x49/0x5b
 [<c04dff06>] blkdev_ioctl+0x714/0x762
 [<c0479933>] block_ioctl+0x16/0x1b
 [<c048317e>] do_ioctl+0x22/0x67
 [<c048341b>] vfs_ioctl+0x258/0x26b
 [<c0483475>] sys_ioctl+0x47/0x62
 [<c0403fb7>] syscall_call+0x7/0xb
DWARF2 unwinder stuck at syscall_call+0x7/0xb
Leftover inexact backtrace:
 [<c04057fa>] show_trace+0xd/0x10
 [<c0405913>] dump_stack+0x19/0x1b
 [<c043b10f>] print_circular_bug_tail+0x59/0x64
 [<c043b898>] __lock_acquire+0x77e/0x90d
 [<c043bf98>] lock_acquire+0x4b/0x6b
 [<c06135f3>] __mutex_lock_slowpath+0xbc/0x20a
 [<c0613762>] mutex_lock+0x21/0x24
 [<c0479c8a>] bd_claim_by_disk+0x5f/0x169
 [<c05a16ca>] bind_rdev_to_array+0x20a/0x228
 [<c05a3571>] autorun_devices+0x1c8/0x29d
 [<c05a5dea>] md_ioctl+0x104/0x1540
 [<c04df7e0>] blkdev_driver_ioctl+0x49/0x5b
 [<c04dff06>] blkdev_ioctl+0x714/0x762
 [<c0479933>] block_ioctl+0x16/0x1b
 [<c048317e>] do_ioctl+0x22/0x67
 [<c048341b>] vfs_ioctl+0x258/0x26b
 [<c0483475>] sys_ioctl+0x47/0x62
 [<c0403fb7>] syscall_call+0x7/0xb

Version-Release number of selected component (if applicable):
Linux version 2.6.18-1.2708.fc6 SMP

How reproducible: always

Steps to Reproduce:
1. dmesg

Additional info:
BIOS Ver. 0408
Motherboard: P5WDG2-WS-PRO