Created attachment 74241 [details]
output after "echo w >/proc/sysrq-trigger"

Distribution: Fedora 15
Kernel 3.1
upower 0.9.12-1

Problem Description:
Every now and then several tasks on my system are getting stuck in D-State:
upowerd
[kworker/0:1]
cat /proc/acpi/battery/BAT1/*
cat /sys/class/thermal/cooling_device0/cur_state

Plus a program I wrote to read the systems temperature from /sys filesystem using 
std::fstream classes.

I use another program to query the systems battery information via the DBUS interface of upower which give this error message once upowerd is stuck:

failed to set path: cannot refresh: Cannot get device properties for /org/f
reedesktop/UPower/devices/battery_BAT1: Couldn't call GetAll() to get prope
rties for /org/freedesktop/UPower/devices/battery_BAT1: Did not receive a r
eply. Possible causes include: the remote application did not send a reply,
 the message bus security policy blocked the reply, the reply timeout expir
ed, or the network connection was broken.

If you need more information, please ask and I'll try to provide it.
The problem occurs relatively seldom. But when I read the systems battery information using the I2C bus, the chance to see this problem increases.
I got this several times directly after reading the battery via I2C.