Re: [PATCH 1/1] ath5k: fix hw rate index condition

Dhaval Giani
2009-03-31T03:52:58Z

On Mon, Mar 30, 2009 at 02:13:35PM -0400, Bob Copeland wrote:
> On Mon, Mar 30, 2009 at 1:59 PM, Dhaval Giani <dhaval@linux.vnet.ibm.com> wrote:
> > ok, so my kernel does hve this patch applied, and this is what I get,
> >
> >  ------------[ cut here ]------------
> >  WARNING: at include/net/mac80211.h:1956 minstrel_get_rate+0xa1/0x4b9 [mac80211]()
>
> I believe this is something different (tx path not rx). I think it's
> that minstrel rate table bug again, which we never solved for ath5k.
>
> Are you using adhoc or managed mode? Do you have the slab/slub debugging
> options turned on? Any steps that consistently reproduce it? Do you
> get any warnings with PID controller?
>

[dhaval@gondor ~]$ iwconfig wlan0
wlan0 IEEE 802.11abg ESSID:"linksys_SES_62338"
Mode:Managed Frequency:2.462 GHz Access Point: 00:1A:70:D6:2D:06
Bit Rate=36 Mb/s Tx-Power=23 dBm
Retry min limit:7 RTS thr:off Fragment thr=2352 B
Power Management:off
Link Quality=100/100 Signal level:-49 dBm Noise level=-96 dBm
Rx invalid nwid:0 Rx invalid crypt:0 Rx invalid frag:0
Tx excessive retries:0 Invalid misc:0 Missed beacon:0

[dhaval@gondor ~]$

[dhaval@gondor linux-2.6]$ grep -i slub .config
CONFIG_SLUB_DEBUG=y
CONFIG_SLUB=y
# CONFIG_SLUB_DEBUG_ON is not set
# CONFIG_SLUB_STATS is not set
[dhaval@gondor linux-2.6]$

Am not sure what the PID controller is, and google gave me a number of
results, which did not make too much sense in the context.

Yes, I think I know how to reproduce it, but I am not sure what is the
real cause.

One way I have found of reproducing it is to connect to open networks,
but it does not happen always. At home, when my network is set to open,
I do not see this issue, whereas at the airport, kaboom.

I've also seen it on LEAP networks, but there were also a few open
networks around. This warning is generally accompanied by a disconnect
from the LEAP connected network, and then the system reconnects. Let me
know if you have patches, I can give them a run and report back.

Thanks,
--
regards,
Dhaval