Re: Panic in rum(4) on 8.0-BETA2

Hans Petter Selasky wrote:

> This looks like a WLAN problem rather than an USB problem. Some months back 
> the WLAN statemachine was converted to taskqueues. In that regard I've seen 
> 100% reproducable panics, but I did not have time to investigate. If you put 
> some delay between the "ifconfig" commands on your wlan device, does the 
> problem disappear?

The rum driver violates locking requirements by dropping the net80211 
lock in the driver's newstate method in order to pickup the driver softc 
to do usb operations.  This opens a race whereby wpa_supplicant makes a 
request that clocks the state machine again causing a state transition 
to be lost:

wlan0: ieee80211_new_state_locked: pending SCAN -> AUTH transition lost

This in turns causes net80211 state to be wrong and causes the crash.

I will need to understand why the above is done to see if the driver can 
be changed to do what is required.  I also note other bugs in this 
routine that can cause further problems.

	Sam