XFS error

[Dmitry Katsubo <dma_k@xxxxxxx>]

Hi, XFS developers!

I am using CVS 2.4.18-xfs kernel, and after the latest
update and reboot I found the next error. The system continues
running after it. Suppose, it would help you
in finding the problem.

kernel: Unable to handle kernel NULL pointer dereference at virtual address 0000000c
kernel:  printing eip:
kernel: c01fb3b6
kernel: *pde = 00000000
kernel: Oops: 0000
kernel: CPU:    0
kernel: EIP:    0010:[cluster_write+6/272]    Not tainted
kernel: EIP:    0010:[<c01fb3b6>]    Not tainted
kernel: EFLAGS: 00010246
kernel: eax: 00000000   ebx: 00000000   ecx: dfa36860   edx: ce3410c8
kernel: esi: c17b7e8c   edi: c1356d20   ebp: 00000000   esp: c17b7e54
kernel: ds: 0018   es: 0018   ss: 0018
kernel: Process kupdated (pid: 7, stackpage=c17b7000)
kernel: Stack: 00000000 c17b7e8c c1356d20 00000001 c01fb55f df64b340 ce3410c0 c1356d20
kernel:        c17b7e8c 00000001 00010002 c01fed80 00000001 00000001 02756ec8 00000000
kernel:        00000000 00000000 00000000 00080000 00000001 00000047 c1356d20 0007f291
kernel: Call Trace: [pagebuf_delalloc_convert+159/192] [linvfs_pb_bmap+0/208] [pagebuf_write_full_page+127/224] 
[linvfs_pb_bmap+0/208] [xfs_write_full_page+37/64]
kernel: Call Trace: [<c01fb55f>] [<c01fed80>] [<c01fa40f>] [<c01fed80>] [<c01feff5>]
kernel:    [linvfs_pb_bmap+0/208] [linvfs_write_full_page+135/176] [write_buffer_delay+85/96] 
[write_some_buffers+237/272] [schedule+489/880]
[flush_old_commits+239/352]
kernel:    [<c01fed80>] [<c01ff177>] [<c01314f5>] [<c013176d>] [<c0112589>] [<c019766f>]
kernel:    [sync_unlocked_inodes+246/352] [process_timeout+0/80] [sync_old_buffers+28/64] [kupdate+247/256] 
[_stext+0/48] [kernel_thread+38/48]
kernel:    [<c0142806>] [<c01122a0>] [<c01344fc>] [<c01347a7>] [<c0105000>] [<c0105526>]
kernel:    [kupdate+0/256]
kernel:    [<c01346b0>]
kernel:
kernel: Code: 8b 45 0c 31 ff 8b 48 0c 85 c9 74 51 8b 5d 10 8b 43 08 8b 53