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Date: Tue, 17 Mar 2009 13:41:54 +0000
From: Bruce Simpson <bms@incunabulum.net>
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To: Coleman Kane <cokane@FreeBSD.org>
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Cc: Sam Leffler <sam@freebsd.org>, current@freebsd.org,
	freebsd-net <net@freebsd.org>
Subject: Re: IGMP+WiFi panic on recent kernel - in igmp_fasttimo()
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Coleman Kane wrote:
> If you are looking for a reliable test case, this might be it for you,
> but I think you need a wlan interface to test it with:
>   * Install net/avahi from ports
>   * Set avahi_daemon_enable="YES" in rc.conf
>   * Configure VAP params for wlan0 card in rc.conf
>   * Log in and run "dhclient wlan0" to trigger the panic
>
>   

Actually I was able to panic the kernel right away with the 802.11 code, 
just
by joining a multicast group with mtest(8) on the wlan interface.

i.e.

# mtest
j 224.0.0.2 192.168.x.x
-> boom

I believe I've found the symptom, but the root cause I don't fully 
understand.
Sam indicated that the VAP code is using ifma's in some nested way between
the ifnets which comprise the VAP's member interfaces.

A workaround is pending....

cheers
BMS