Debugging problems resulting in Prism2 firmware crash

Jouni Malinen jkmaline at
Sun Mar 2 22:54:17 EST 2003

There have been number of reports about problems that seem to be related
to the command completion event handling in the current Host AP driver.
These problems usually show in dmesg output as hfa384x_cmd errors "entry
still in list" or "command was not completed".

The best method for debugging this kind of errors would be logic
analyzer on PC Card connector. However, most people using Host AP driver
probably do not have access to such equipment. I just added some
debugging code to CVS for emulating logic analyzer. This is not perfect,
but can give useful debugging information. 

If the CVS version of the driver is compiled with PRISM2_IO_DEBUG (see
driver/modules/hostap_config.h), last 5000 I/O operations with results
are stored in host side buffer that can be accesses from user space
using hostap_io_debug (in 'utils' directory).

If you are getting frequent problems that seem to crash the Prism2 wlan
card, please try this method for collecting debugging information.
Compile the driver with PRISM2_IO_DEBUG and send me output of 'dmesg'
and 'hostap_io_debug /proc/net/hostap/wlan0/io_debug' commands after the
error situation has occurred.

Jouni Malinen                                            PGP id EFC895FA

More information about the HostAP mailing list