oops when calling dm_set_disp()

[Damian Hazen <dhazen@xxxxxxx>]

Hi -

I'm using XFS/DMAPI with a 2.6.10 kernel pulled from the CVS repository 
a couple of days ago.  I'm regularly getting an oops when calling 
dm_set_disp() after receiving a mount event but before responding.  This 
has worked well for us in the past.  Any insights into what's changed?

Thanks,
-Damian

Unable to handle kernel NULL pointer dereference at virtual address 0000000c
 printing eip:
c0243d28
*pde = 00000000
Oops: 0000 [#1]
SMP
Modules linked in: nvram speedstep_lib freq_table thermal processor fan 
button battery ac ipv6 edd e1000 evdev joydev sg st sd_mod sr_mod 
scsi_mod ide_cd cdrom pcnet32 mii i2c_i801 i2c_core uhci_hcd dm_mod 
usbcore reiserfs
CPU:    1
EIP:    0060:[<c0243d28>]    Not tainted VLI
EFLAGS: 00010246   (2.6.10-sgi-xfs-dmapi)
EIP is at dm_handle_to_ip+0x118/0x290
eax: 00000000   ebx: f4fc0b48   ecx: 00000000   edx: f4fc0b90
esi: f73e3400   edi: f4fc27a4   ebp: f4fc0b84   esp: f5055d6c
ds: 007b   es: 007b   ss: 0068
Process hpss_hdm (pid: 9782, threadinfo=f5054000 task=f5314020)
Stack: 000000d0 00000000 c0415f00 dffff480 f4fc0b90 f5055e94 00000000 
f4fc2782
       f5345e88 00000000 00000000 00000001 00000000 f5314020 00000010 
c0418400
       c0142851 f4fc2018 dfd58c08 dfd58c40 dfd58c10 000000d0 dfd58b80 
dfd58b80
Call Trace:
 [<c0142851>] cache_alloc_refill+0x151/0x240
 [<c0245824>] dm_app_lookup_tdp+0x274/0x460
 [<c0245475>] dm_init_tevp+0x25/0xc0
 [<c0246f12>] dm_find_session_and_lock+0x62/0x70
 [<c0245bd3>] dm_app_get_tdp+0x123/0x130
 [<c0244c0a>] dm_set_disp+0x13a/0x290
 [<c026a377>] __copy_from_user_ll+0x57/0x70
 [<c02401c9>] dmapi_ioctl+0x2a9/0x920
 [<c01594b9>] fget+0x49/0x60
 [<c016a6fb>] sys_ioctl+0x1ab/0x240
 [<c0127456>] sys_rt_sigprocmask+0x46/0xd0
 [<c01038dd>] sysenter_past_esp+0x52/0x75
Code: 24 8b 43 1c ff 4b 4c 85 c0 0f 85 5b ff ff ff ff 43 50 8b 44 24 10 
e8 f8 b2 16 00 8b 44 24 14 8b 73 04 66 83 38 00 75 57 8b 46 3c <8b> 40 
0c 89 44 24 20 e8 9c df f2 ff 8b 44 24 10 31 ff e8 a1 b2