Re: mac80211 warning in 3.9.0+ when unloading ath9k driver.

[Ben Greear <greearb@candelatech.com>]

On 05/08/2013 11:04 AM, Johannes Berg wrote:
> On Wed, 2013-05-08 at 10:38 -0700, Ben Greear wrote:
>> I saw the WARN_ON_ONCE hit below on 3.9.0+ (+ hacks)
>> on a system with ath9k and ath9k_htc driver.
>
> Were you using VLANs?

No.

>
>> I'll be happy to add more debugging if someone has suggestions.
>
>> 		compat = cfg80211_chandef_compatible(
>> 				&sdata->vif.bss_conf.chandef, compat);
>> 		if (!compat)
>> 			break;
>> 	}
>> 	rcu_read_unlock();
>>
>> 	if (WARN_ON_ONCE(!compat))
>> 		return;
>
> Might be helpful to know whether chandef_compatible() returned NULL, or
> if the loop simply never found an interface with a matching pointer.

Ok, I'll add this.

Probably un-related, but the system usually crashes shortly after.  With
memory debugging enabled, it appears to be relayfs and/or ath9k accessing
freed memory.

I'm digging into that one first on an un-hacked kernel..then will
get back to this warning...

Thanks,
Ben

>
> johannes
>


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com