I'm developing a embeded system DVR on Au1500 which based on mips arch.The linux kernel is Montavista linux kernel2.4.20，The file system type is jffs2 and harddisk is based on ATA! Only when write the buffer data to harddisk for a short time(about 12 hours), It's easy to cause the kernel oops as the following! The buffer size is 256KBytes(any question with the buffer size?).

kernel oops :
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BUG at jfs_dmap.c:2870 assert(n < 4)
kernel BUG at jfs_dmap.c:2870!
Unable to handle kernel paging request at virtual address 00000000, epc == 801c2ee4, ra == 801c2ee4
Oops in fault.c:do_page_fault, line 213:
$0 : 00000000 1000fc00 0000001f 00000000 8036e9d0 00000001 00000001 00000000
$8 : 00000001 0000314e 00004001 803a8f9d fffffff8 ffffffff 0000000a 00000003
$16: 00000004 00000001 00000059 00000000 00000059 845cd010 86cd5c30 85bb8380
$24: 86cd5b03 803a937f 86cd4000 86cd5be8 00000000 801c2ee4
Hi : ffff2e99
Lo : 000045cd
epc : 801c2ee4 Not tainted
Status: 1000fc03
Cause : 0080000c
Process edvr (pid: 297, stackpage=86cd4000)
Stack: 87fc0c28 8030f278 00000b36 00000000 00000000 00000000 845cd000
85af0000 00000001 00000000 00000000 801c1b2c 86cd5c20 00000000 00000000
00000000 00032020 00000000 00000005 85af0000 0000001c 00000000 0000001c
85af0000 00000001 801c0234 85af0000 87fc0bdc 00032020 00000000 86cd5cd0
00000000 86cd5cd0 00000000 845cd000 00000000 87fc0c28 80361aa8 00000001
00000000 ...
Call Trace: [<8030f278>] [<801c1b2c>] [<801c0234>] [<801cce50>] [<801cc7fc>]
[<801ccbb8>] [<801b12ec>] [<80146d8c>] [<80146f1c>] [<8014786c>] [<801b1198>]
[<801b14d8>] [<80223fd4>] [<80134058>] [<80134100>] [<801223d8>] [<801344dc>]
[<801564c8>] [<8014338c>] [<80107ba4>] [<80107ba4>]

Code: 24a5f278 0c04624b 24060b36 <ac000000> 02501021 00021080 2631ffff 1e20ffe1 24520001
Aborted
Rebooting...
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Now I have no better way to debug the kernel and figure out the reason!
For debugging the linux kernel, i'm a new comer! Hope all give some suggestions or the cause for the problem! Thanks!