Comment 21 for bug 460857

typing "dmesg |grep khubd" yields"

[ 960.991399] INFO: task khubd:40 blocked for more than 120 seconds.
[ 960.991411] khubd D 0000000000000000 0 40 2 0x00000000
[ 1080.990369] INFO: task khubd:40 blocked for more than 120 seconds.
[ 1080.990381] khubd D 0000000000000000 0 40 2 0x00000000
[ 1200.990359] INFO: task khubd:40 blocked for more than 120 seconds.
[ 1200.990371] khubd D 0000000000000000 0 40 2 0x00000000
[ 1320.990347] INFO: task khubd:40 blocked for more than 120 seconds.
[ 1320.990359] khubd D 0000000000000000 0 40 2 0x00000000

Does that mean it's crashed? It still shows up when I type "ps aux".

If I type "sudo lsof |grep -i usb" I get:

lsof: WARNING: can't stat() fuse.gvfs-fuse-daemon file system /home/david/.gvfs
      Output information may be incomplete.
usbhid_re 382 root cwd DIR 8,17 4096 2 /
usbhid_re 382 root rtd DIR 8,17 4096 2 /
usbhid_re 382 root txt unknown /proc/382/exe
usb-stora 388 root cwd DIR 8,17 4096 2 /
usb-stora 388 root rtd DIR 8,17 4096 2 /
usb-stora 388 root txt unknown /proc/388/exe
hald 978 haldaemon mem REG 8,17 361263 7354 /var/lib/misc/usb.ids
devkit-po 1770 root mem REG 8,17 35944 662 /lib/libusb-0.1.so.4.4.4
gnome-ses 1908 david mem REG 8,17 35944 662 /lib/libusb-0.1.so.4.4.4
gnome-pow 2099 david mem REG 8,17 35944 662 /lib/libusb-0.1.so.4.4.4

"uname -a" gives me:

Linux studyHP 2.6.31-16-generic #53-Ubuntu SMP Tue Dec 8 04:02:15 UTC 2009 x86_64 GNU/Linux

When it gets like this, the only way I've found to get the ttyUSB0 to go away is to reboot.
One more question - do I need to chown the ttyUSB0 device? It always appears as being owned by root. I've tried changing it and that doesn't seem to make any difference.