random exception on ppc based board

[Thirumalai]

Hi,
    I am having a ppc based target on which linux-2.4.20 kernel is running 
with u-boot 1.3.4 as boot loader. The target is having MPC7410 as processor 
and MPC107 as system controller. Regarding memory it is having 128 MB of ram 
and 16 MB of Flash memory. Also the kernel is patched with RTLinux-3.2 for 
realtime performance. I am getting a random Program and DSI exception on the 
target. Normally the exeption occurs during loading of rtl_time.o. The panic 
message is given below.

==================
Using /usr/rtlinux/modules/rtl_time.okernel BUG at page_alloc.c:221!
Oops: Exception in kernel mode, sig: 4
NIP: C0032980 XER: 00000000 LR: C0032980 SP: C7CEDBA0 REGS: c7cedaf0 TRAP: 
0700    Not tainted
MSR: 00089032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
TASK = c7cec000[366] 'exe' Last syscall: 3
last math c7cec000 last altivec 00000000
GPR00: C0032980 C7CEDBA0 C7CEC000 00000020 00000001 00000001 00001137 
00000000
GPR08: 00000002 00000000 CD879EC0 C7CEDAB0 CD876108 C0011934 00000000 
00000000
GPR16: 00000004 00000001 C002A0E8 C789E840 00009032 07CEDD90 C01A2C70 
C01A2C70
GPR24: 00000001 00000000 C016E080 00000000 C79966E0 00000000 C016E0B8 
C016E0C4
Call backtrace:
C0032980 C0033020 C0032C4C C0025A18 C0025B58 C0025D8C C000EF88
C0005D48 C03A8B28 C0029B28 C002A258 C003A99C C0005AFC 00000000
0FF15DBC 0FF175DC 0FF09894 10012190 100127D0 100356AC 100352A4
0FEBCF6C 00000000

Oops: kernel access of bad area, sig: 11
NIP: C00326DC XER: 00000000 LR: C0032588 SP: C7CED880 REGS: c7ced7d0 TRAP: 
0300    Not tainted
MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
DAR: 00000000, DSISR: 42000000
TASK = c7cec000[366] 'exe' Last syscall: 3
last math c7cec000 last altivec 00000000
GPR00: 00000000 C7CED880 C7CEC000 C7CED888 FFFFFFFF 30026000 C0388250 
00000000
GPR08: 00008000 00000000 00155210 00000000 CD876CD4 C0032588 00000000 
00000000
GPR16: 00000004 00000001 C002A0E8 C789E840 00009032 C01A2C70 C01A2C70 
C016E130
GPR24: C0233024 C0388234 00003E06 00007C0C C016E080 FFFFFFFE C016E0B8 
C0388260
Call backtrace:
C003249C C0033398 C0033B18 C00243D8 C0026234 C00246D0 C0027A70
C001326C C00187D4 C0005ED4 C0005F44 C00062B0 C0005D48 C0032980
C0033020 C0032C4C C0025A18 C0025B58 C0025D8C C000EF88 C0005D48
C03A8B28 C0029B28 C002A258 C003A99C C0005AFC 00000000 0FF15DBC
0FF175DC 0FF09894 10012190 100127D0 100356AC
Illegal instruction
========
Sometimes i am getting the following panic message.
===========
Oops: kernel access of bad area, sig: 11
NIP: C0033360 XER: 20000000 LR: C00DE9A8 SP: C016C0D0 REGS: c016c020 TRAP: 
0300    Tainted: P
MSR: 00009032 EE: 1 PR: 0 FP: 0 ME: 1 IR/DR: 11
DAR: 03910018, DSISR: 40000000
TASK = c016a480[0] 'swapper' Last syscall: 120
last math c505c000 last altivec 00000000
GPR00: C00DE9A8 C016C0D0 C016A480 03910000 00000000 00000000 C5A469DC 
FFFFFFFF
GPR08: 00000001 03910014 00000043 C5A2FE20 2490C022 C0030A04 07FF0D00 
00000000
GPR16: 00044008 00000000 00000000 00000000 00001032 00000003 FFFFFFFF 
0A050393
GPR24: C5A46980 C5A2F842 00000040 00000000 C5A2F842 C01C0000 C5A46980 
00000001
Call backtrace:
00000040 C00DE9A8 C00DE9DC C00DEB28 C01163D4 C01166EC C00F4898
C00F44E4 C00F4AC8 C00F468C C00E3664 C00E3810 C00E397C C001A200
C0007620 CD876CAC C0005D40 C000744C C0007460 C0003918 C01815E0
000035F0
Kernel panic: Aiee, killing interrupt handler!
In interrupt handler - not syncing
 <0>Rebooting in 180 seconds..
================


How to debug this???

-Thirumalai