On Thu, 5 Apr 2007, Jack Vogel wrote:
Our test group uses a script that does 100 iterations of
a module load, then bring up all interfaces, and then
unload driver.
Depending on the system in anything from just a few
iterations to 20 or more, the system will panic.
Just a "me too" here. :p
Its doing an em_detach() which calls ether_ifdetach()
which goes to if_detach, in_delmulti_ifp, in_delmulti_locked,
and finally if_delmulti().
The panic is always happening on a cmpxchgq instruction
so I assume its the LOCK macro, whats odd is that its
not always the same reason, sometimes one register is
0 so its a page fault trap, but on other iterations its a
general protection fault because the register is some
big invalid number :)
I run into this panic regularly. Apparently the result and condition
to trigger the panic are the same as yours: running "while true; do
ifconfig xxx up; kldunload if_xxx; done" and ending up with panicking
at the cmpxchgq instruction.
I am hardpressed to see this as a driver problem, but
I'm willing to be proven wrong, does someone who
knows the stack code better than me have any insights
or ideas?
It also appears system dependent, I have a couple
machines I've tried to reproduce in on and have been
unable. I also am told it happens on both amd64 and
i386, but it seems easier to reproduce on the former.
Dunno about amd64 since I only have i386 around; however, I'm sure
the panic I observed is reproducible on my -CURRENT driver development box.
Lastly, from evidence so far I think this doesnt happen
on CURRENT, but the test group hasnt checked that
only I have and I dont have as much hardware :)
FWIW, I usually run into this panic after upgrading to a newer HEAD.
Sometimes I can make the aforementioned ifconfig/kldunload script to
survive longer by doing a clean rebuild on my driver.
--
Cheers,
Tai-hwa Liang
_______________________________________________
freebsd-net@freebsd.org mailing list
http://lists.freebsd.org/mailman/listinfo/freebsd-net
To unsubscribe, send any mail to "[EMAIL PROTECTED]"
