Kernel crash!

Haven't had one of these in a while. Caps lock and scroll lock suddenly started flashing at me. No morse code though, unless it was meant to be just and endless ............ as in the Morse error symbol.

What was I doing? I was grabbing frames from the webcam. It had been going fine a while earlier, when I used a shell script to take one frame at a time, but now I'm trying to let webcam grab multiple frames separated by 0.2 seconds (hint: it can't - the delay parameter is an integer).

System info:

Linux bernd-desktop 2.6.31-22-generic #68-Ubuntu SMP Tue Oct 26 16:38:35 UTC 2010 i686 GNU/Linux

Modules:

Module                  Size  Used by
binfmt_misc             8356  1
nfsd                  241104  9
lockd                  67724  1 nfsd
nfs_acl                 2844  1 nfsd
auth_rpcgss            36672  1 nfsd
sunrpc                191776  8 nfsd,lockd,nfs_acl,auth_rpcgss
exportfs                4412  1 nfsd
snd_hda_codec_realtek   203328  1
snd_hda_intel          27016  2
snd_hda_codec          75708  2 snd_hda_codec_realtek,snd_hda_intel
snd_usb_audio          84224  2
snd_usb_lib            16284  1 snd_usb_audio
snd_pcm_oss            37920  0
snd_mixer_oss          16028  1 snd_pcm_oss
snd_seq_dummy           2656  0
snd_pcm                75296  4 snd_hda_intel,snd_hda_codec,snd_usb_audio,snd_pcm_oss
snd_hwdep               7200  2 snd_hda_codec,snd_usb_audio
snd_seq_oss            28608  0
snd_seq_midi            6464  0
snd_rawmidi            22176  2 snd_usb_lib,snd_seq_midi
snd_seq_midi_event      6940  2 snd_seq_oss,snd_seq_midi
snd_seq                50224  6 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_seq_midi_event
snd_timer              22276  2 snd_pcm,snd_seq
snd_seq_device          6920  5 snd_seq_dummy,snd_seq_oss,snd_seq_midi,snd_rawmidi,snd_seq
snd                    59236  21 snd_hda_codec_realtek,snd_hda_intel,snd_hda_codec,snd_usb_audio,snd_pcm_oss,snd_mixer_oss,snd_pcm,snd_hwdep,snd_seq_oss,snd_rawmidi,snd_seq,snd_timer,snd_seq_device
iptable_filter          3100  0
ppdev                   6688  0
soundcore               7264  1 snd
parport_pc             31940  1
snd_page_alloc          9156  2 snd_hda_intel,snd_pcm
gspca_zc3xx            47580  0
ip_tables              11692  1 iptable_filter
x_tables               16544  1 ip_tables
gspca_main             22812  1 gspca_zc3xx
pwc                    81632  0
videodev               36736  2 gspca_main,pwc
v4l1_compat            14336  1 videodev
psmouse                57332  0
serio_raw               5280  0
lp                      8964  0
parport                35340  3 ppdev,parport_pc,lp
fbcon                  36640  72
tileblit                2460  1 fbcon
font                    8124  1 fbcon
bitblit                 5372  1 fbcon
softcursor              1756  1 bitblit
floppy                 54916  0
8139too                22620  0
8139cp                 19260  0
mii                     5212  2 8139too,8139cp
i915                  227528  3
drm                   160096  3 i915
i2c_algo_bit            5760  1 i915
video                  19380  1 i915
output                  2780  1 video
intel_agp              27996  2 i915
agpgart                34988  2 drm,intel_agp

And my ~/.webcamrc:

[grab]
device = /dev/video0
text = "%Y-%m-%d %H:%M:%S"
infofile = foo
fg_red = 255
fg_green = 255
fg_blue = 255
width = 640
height = 480
delay = 0.2
wait = 3
input = usb
#norm = pal
rotate = 0
top = 0
left = 0
bottom = -1
right = -1
quality = 75
trigger = 0
once = 0

[ftp]
host = localhost
user = webcam
pass = xxxxxx
dir  = public_html/snapshots
file = webcam.jpeg
tmp  = uploading.jpeg
passive = 1
debug = 1
auto = 0
local = 1
ssh = 0

Finally, the script:

#!/bin/sh

i=1
while true; do
 sleep 0.1
 webcam >/dev/null 2>&1 &
 mv public_html/snapshots/webcam.jpeg `date +public_html/snapshots/webcam-%Y%m%d-%H%M%S-$i.jpeg` || continue
 i=$(($i+1))
done

Astute readers will notice that it's a forkbomb-lite, spawning a new webcam process every 0.1 seconds! Still, no userland process should be able to make the kernel panic, right?

I don't really feel like investigating this too far. Reboots are SO disruptive!