panic with if_iwi(4) upon "netif restart"

[Bernhard Schmidt]

On Mon, May 7, 2012 at 5:54 AM, Alexey Dokuchaev <danfe at nsu.ru> wrote:
> Folks,
>
> Weird panic occurs to me here with iwi(4) based laptop when trying to hook
> up to WPA-protected network with "service netif restart".  Kernel and
> userland are not strictly in sync, with the latter lagging behind couple
> of months, but presumably this fact should not matter on stable branch.
>
> I was only able to get online by manually running wpa_supplicant(8) and
> dhclient(8).  if_iwi(4) loaded after system fully boots (i.e. manually after
> login).
>
> [snip]
>
> Feel free to ask for more information.

does "ps" in kgdb reveal multiple instances of wpa_supplicant running?
If so, this seems to be the well known devd+netif+supplicant+newstate
race/missing refcount.

Wanna try attached patch?

-- 
Bernhard
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