While running file system stress (fsstress) on a JFS partition
with 2.6.29-rc8, i hit the following BUG.

------------[ cut here ]------------
kernel BUG at fs/mpage.c:473!
cpu 0x0: Vector: 700 (Program Check) at [c0000000be9daba0]
    pc: c00000000014e3a0: .__mpage_writepage+0xd0/0x630
    lr: c0000000000dfedc: .write_cache_pages+0x288/0x42c
    sp: c0000000be9dae20
   msr: 8000000000029032
  current = 0xc00000003f30dd10
  paca    = 0xc000000000753400
    pid   = 27402, comm = fsstress
kernel BUG at fs/mpage.c:473!
enter ? for help
[c0000000be9db3a0] c0000000000dfedc .write_cache_pages+0x288/0x42c
[c0000000be9db530] c00000000014e298 .mpage_writepages+0x54/0x8c
[c0000000be9db5d0] d0000000032f1720 .jfs_writepages+0x1c/0x34 [jfs]
[c0000000be9db650] c0000000000e0120 .do_writepages+0x68/0xa4
[c0000000be9db6d0] c0000000000d764c .__filemap_fdatawrite_range+0x8c/0xbc
[c0000000be9db7c0] c0000000000d76bc .filemap_write_and_wait_range+0x40/0x8c
[c0000000be9db860] c0000000000d79f4 .generic_file_buffered_write+0x2ec/0x358
[c0000000be9db9a0] c0000000000d7f88
.__generic_file_aio_write_nolock+0x300/0x3ec
[c0000000be9dbaa0] c0000000000d8390 .generic_file_aio_write+0x80/0x114
[c0000000be9dbb60] c000000000118a24 .do_sync_write+0xc4/0x124
[c0000000be9dbcf0] c00000000011959c .vfs_write+0xd8/0x1a4
[c0000000be9dbd90] c000000000119768 .SyS_write+0x50/0x90
[c0000000be9dbe30] c000000000008534 syscall_exit+0x0/0x40
--- Exception: c01 (System Call) at 000000000ff0d8c8
SP (ff87c6f0) is in userspace

This is a powerpc box (IBM,9133-55A). I have attached the dmesg log
as well as the jfs-fsstress.log

Partition Table information : 

/dev/sda3 on / type ext3 (rw)
proc on /proc type proc (rw)
sysfs on /sys type sysfs (rw)
devpts on /dev/pts type devpts (rw,gid=5,mode=620)
/dev/sda2 on /boot type ext3 (rw)
tmpfs on /dev/shm type tmpfs (rw)
none on /proc/sys/fs/binfmt_misc type binfmt_misc (rw)
sunrpc on /var/lib/nfs/rpc_pipefs type rpc_pipefs (rw)
/dev/sda6 on /mnt/tmp type jfs (rw)

Let me know if there is any other information that i can provide.

Thanks
-Sachin


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Sachin Sant
IBM Linux Technology Center
India Systems and Technology Labs
Bangalore, India
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