Hard(?) lock when reassociating ath with wpa_supplicant on RELENG_7

[Alexandre "Sunny" Kovalenko]

On Fri, 2008-07-11 at 20:29 -0700, Sam Leffler wrote:
> Alexandre "Sunny" Kovalenko wrote:
> > On Fri, 2008-05-16 at 12:23 -0400, Sam Leffler wrote:
> >> Alexandre "Sunny" Kovalenko wrote:
> >>> On Mon, 2008-05-12 at 19:33 -0700, Sam Leffler wrote: 
> >>>> Alexandre "Sunny" Kovalenko wrote:
> >>>>> I seem to be able to lock my machine by going into wpa_cli and asking it
> >>>>> to 'reassoc'. The reason for question mark after "hard" is that debug
> >>>>> information (caused by wlandebug and athdebug) is being printed on the
> >>>>> console. The only way to get machine's attention is to hold power button
> >>>>> for 8 seconds.
> >>>> So this is just livelock due to console debug msgs.
> >>> I am not sure, I have parsed this well enough, so I will try to clarify:
> >>> machine becomes unresponsive *without* any debugging turned on, to an
> >>> extent that pressing the power button twice *does not* generate ACPI
> >>> console message (something to the tune of "going into S5 already --
> >>> gimme a break"). If I turn ath debugging on, I do see those messages,
> >>> and only them, scrolling on the console.
> >> Guess I misunderstood you.
> > 
> > I have finally got enough time and equipment to investigate this
> > further. Here are some conclusions:
> > 
> > -- at this point (RELENG_7 as of July 9th around 15:30 EST) it is indeed
> > a livelock.
> > 
> > -- all system does, is executing ath_intr (if_ath.c) in the tight loop
> > with the same status -- 0x1000 AKA HAL_INT_MIB. In order to eliminate
> > possibility that I have caused livelock with the debug messages, I have
> > put conditional panic() into ath_intr, as soon as sc->sc_stats.ast_mib
> > reaches 10,000. Without any kind of the debug messages, it will be
> > triggered within 40-60 seconds after starting of wpa_supplicant.
> > 
> > -- I suspect that comment below, might not hold true on my equipment
> > if (status & HAL_INT_MIB) {
> >    sc->sc_stats.ast_mib++;
> >    /*
> >     * Disable interrupts until we service the MIB
> >     * interrupt; otherwise it will continue to fire.
> >     */
> >    ath_hal_intrset(ah, 0);
> >    /*
> >     * Let the hal handle the event.  We assume it will <============
> >     * clear whatever condition caused the interrupt.   <============
> >     */
> >     ath_hal_mibevent(ah, &sc->sc_halstats);
> >     ath_hal_intrset(ah, sc->sc_imask);
> > }
> > 
> > My hardware is:
> > ath_hal: 0.9.20.3 (AR5210, AR5211, AR5212, RF5111, RF5112, RF2413,
> > RF5413)
> > ath0: <Atheros 5212> mem 0xedf00000-0xedf0ffff irq 17 at device 0.0 on
> > pci3
> > ath0: [ITHREAD]
> > ath0: using obsoleted if_watchdog interface
> > ath0: Ethernet address: 00:16:cf:26:2f:3f
> > ath0: mac 10.3 phy 6.1 radio 10.2
> > 
> > My wpa_supplicant.conf is:
> > ctrl_interface=/var/run/wpa_supplicant
> > ctrl_interface_group=wheel
> > eapol_version=2
> > 
> > network={
> >   ssid="XXXXXXXXXXX"
> >   scan_ssid=1
> >   priority=1
> >   proto=WPA
> >   pairwise=TKIP
> >   group=TKIP
> >   key_mgmt=WPA-PSK
> >   psk="xxxxxxxxxxxxxxxxxxxxxx"
> > }
> > 
> > Access point is Netgear WNDR3300-1B with 11N and 11G SSID set up to
> > different values. Only 11G SSID is configured in wpa_supplicant.conf. In
> > the test setup, AP is with 10' (3m) from the laptop.
> > 
> > AP is successfully used by handful of Windows clients (including this
> > same laptop) and iBook G4.
> > 
> > Neither wpa_supplicant with '-d -d' nor wlandebug 0xFFFFFFFF show
> > anything but normal scan. 
> > 
> > athdebug 0xFFFFFFFF loops with ath_intr: status 0x1000 until I power
> > down my laptop.
> > 
> > I would appreciate any suggestion on what I can investigate further --
> > at this point I have comfortable console setup and should be able to
> > field requests for further information much better.
> > 
> 
> Are you running powerd?
I do. And I just tried disabling it, and I could not reproduce the
problem any more. Is there any way to reconcile if_ath with powerd?

Thank you,

-- 
Alexandre "Sunny" Kovalenko (Олександр Коваленко)