kernel BUG at kernel/timer.c:414!

kernel BUG at kernel/timer.c:414!
invalid operand: 0000 [#1]
PREEMPT SMP
Modules linked in: md5 ipv6 ub
CPU:    0
EIP:    0060:[<c01256b0>]    Not tainted VLI
EFLAGS: 00010003   (2.6.9-z)
EIP is at cascade+0x40/0x50
eax: c170e920   ebx: f655296   ecx: 00000034  edx:f655296c
esi: c170f2cc   edi: c170e920  ebp: 00000034  esp:c04e3f38
ds: 007b   es: 007b   ss: 0068
Process swapper (pid: 0, threadinfo=c04e2000 task=c0435ac0)
Stack: 00000000 c04e0f08 c170e920 c04e3f50 c0125cb9 00172fcb c04e3f50 c04e3f50
       c179dba0 00000001 c04e0f08 c051ba20 0000000 c0121e06 0000000a 00000046
       00000000 c0519424 00577007 c0121e4d c0519428 v01141nn 04e2000 ffffe000
Call Trace:
 [<c0125cb9>] run_timer_sofirq+0x119/0x170
 [<c0121e06>] __do_softirq+0xb6/0xd0
 [<c0121e4d>] do_softirq+0x2d/0x30
 [<c01141bb>] smp_apic_timer_interrupt+0x8b/0x100
 [<c0105b3a>] default_ide+0x0/0x40
 [<c04e48b6>] start_kernel+-x156/0x180
 [<c04e4370>] unknown_bootoption+0x0/0x180
Code: 90 90 90 90 90 90 90 90 90 90 90 39 7b 1c 89 da 75 19 8b 1b f8 e8 60 fb ff ff 39 f3 75 ec 8
9 36 89 e8 89 76 04 5b 5e 5f 5d c3 <0f> 0b 9e 01 23 1f 3d c0 eb dd 8d b6 00 00 00 00 56 53 83 ec 04 
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