[arch-general] kernel oopses when using modules

[Ryan Sims]

I posted[1] to the forums about this when I thought it was an nvidia
problem, but now it seems to be more general.  I recently upgraded to
kernel26-2.6.23.9-1 from 2.6.23.8-1, and now I get oopses when certain
modules are accessed.  For example:

BUG: unable to handle kernel NULL pointer dereference at virtual
address 0000000b
 printing eip:
c016c4da
*pde = 00000000
Oops: 0000 [#1]
PREEMPT SMP
Modules linked in: ext2 w83627ehf hwmon_vid ipv6 ohci1394 ieee1394
firewire_ohci firewire_core crc_itu_t tsdev usbhid hid ff_memless
usb_storage ide_core intel_agp agpgart ppp_generic sky2 sg evdev
thermal processor fan button battery ac kqemu i2c_i801 i2c_dev
i2c_core coretemp snd_hda_intel snd_pcm snd_timer snd_page_alloc
snd_hwdep snd soundcore slhc skge rtc ext3 jbd mbcache sd_mod sr_mod
cdrom ehci_hcd uhci_hcd usbcore ahci ata_generic pata_jmicron libata
CPU:    1
EIP:    0060:[<c016c4da>]    Not tainted VLI
EFLAGS: 00210206   (2.6.23-ARCH #1)
EIP is at find_vma+0xa/0x70
eax: 00000003   ebx: af09d000   ecx: af09d000   edx: af09d000
esi: 00000003   edi: af09d000   ebp: f5d94000   esp: f490de1c
ds: 007b   es: 007b   fs: 00d8  gs: 0033  ss: 0068
Process qemu (pid: 7434, ti=f490c000 task=f5d94000 task.ti=f490c000)
Stack: 00000114 af09d000 c016cc1d 00000114 f9590000 af09d000 c016b084 f5d94000
       00000003 00000003 00000000 00000022 f9590000 f9590000 f9590000 00000114
       f9590000 f9590000 00000002 f935345f 00000001 00000001 00000000 f490de80
Call Trace:
 [<c016cc1d>] find_extend_vma+0x1d/0x70
 [<c016b084>] get_user_pages+0x44/0x2d0
 [<f935345f>] kqemu_lock_user_page+0x3f/0x80 [kqemu]
 [<f93549d7>] mon_user_map+0xe7/0x110 [kqemu]
 [<f93552cb>] kqemu_init+0x7eb/0xe20 [kqemu]
 [<c016ade1>] handle_mm_fault+0x501/0x760
 [<c016e051>] mmap_region+0x311/0x440
 [<f93531b9>] kqemu_ioctl+0x109/0x120 [kqemu]
 [<c018ae58>] do_ioctl+0x78/0x90
 [<c018b09e>] vfs_ioctl+0x22e/0x2b0
 [<c018b17d>] sys_ioctl+0x5d/0x70
 [<c0104482>] sysenter_past_esp+0x6b/0xa1
 [<c0360000>] wait_for_completion+0x30/0xa0
 =======================
Code: 00 89 d1 8b 50 20 39 ca 73 05 89 48 20 89 ca 8b 48 14 39 d1 73
03 89 48 20 f3 c3 8d b6 00 00 00 00 56 85 c0 53 89 c6 89 d3 74 51 <8b>
50 08 85 d2 74 05 39 5a 08 77 35 8b 4e 04 85 c9 74 3e 31 d2
EIP: [<c016c4da>] find_vma+0xa/0x70 SS:ESP 0068:f490de1c

I don't want to waste the bandwidth, but I have another one very much
like it for nvidia trying to run opengl stuff.  The dmesg above is the
kqemu module and qemu.  I'd suspect hardware, but I don't have any
other reason to, and everything was working fine before the upgrade.
Also, it's only these two modules (so far) and the BUG always happens
at the same place, which seems a little too deterministic to be heat
issues.  I'm not familiar enough with the kernel changelog to be able
to narrow things down that way.  Any help?
-- 
Ryan W Sims