Kernel panic on 2.6.15.4, due to I/O error?

Kernel panic on 2.6.15.4, due to I/O error?

[Li Guanglei]

Today I tried to test LKET on 2.6.15.4 kernel on my Power5, but kernel 
panic very frequently. :-(  error message from xmon:

sysperf12b login: Unable to handle kernel paging request for data at 
address 0x00000014
Faulting instruction address: 0xd00000000027f1b4
cpu 0x3: Vector: 300 (Data Access) at [c0000000428379e0]
     pc: d00000000027f1b4: ._stp_proc_read+0x60/0xac [stap_18355]
     lr: c0000000000b2318: .vfs_read+0xe4/0x1b8
     sp: c000000042837c60
    msr: 8000000000009032
    dar: 14
  dsisr: 40000000
   current = 0xc0000000424517e0
   paca    = 0xc000000000566400
     pid   = 18466, comm = stpd
enter ? for help


3:mon> t
[c000000042837cf0] c0000000000b2318 .vfs_read+0xe4/0x1b8
[c000000042837d90] c0000000000b2714 .sys_read+0x4c/0x8c
[c000000042837e30] c000000000008600 syscall_exit+0x0/0x18
--- Exception: c01 (System Call) at 000000000fc2ca94
SP (f7ecfe00) is in userspace


I am not sure what happened. but I had some troubles with the 
filesystem. It will become Read-Only after some writing operations. I 
am not sure whether this is the reason of kernel panic.

Error Message:

...
end_request: I/O error, dev sda, sector 17445
end_request: I/O error, dev sda, sector 17447
end_request: I/O error, dev sda, sector 17449
Aborting journal on device sda2.
ext3_abort called.
EXT3-fs error (device sda2): ext3_journal_start_sb: Detected aborted 
journal
Remounting filesystem read-only

 From dmesg:

sd 0:0:0:0: SCSI error: return code = 0x8000002
sda: Current: sense key: Hardware Error
     Additional sense: No additional sense information
Info fld=0x0
end_request: I/O error, dev sda, sector 17229
Buffer I/O error on device sda2, logical block 582
lost page write due to I/O error on sda2
sd 0:0:0:0: SCSI error: return code = 0x8000002
sda: Current: sense key: Hardware Error
     Additional sense: No additional sense information
Info fld=0x0

I tried the .config file from arch/powerpc/configs/pseries_defconfig 
and that from /boot/config-2.6.9-30EL. But neither worked for me.

I tried 2.6.9-30EL kernel shipped with RHEL 4 U3. It worked quite well.

So could anybody tell me what happened? Did I missed some options in 
kenrel, or is it just a bug of 2.6.15.4?

Thanks.