Re: wireless-testing (2.6.36-rc6): inconsistent {IN-SOFTIRQ-W} -> {SOFTIRQ-ON-W} usage.

[Ben Greear <greearb@candelatech.com>]

On 10/01/2010 04:49 AM, Johannes Berg wrote:
> On Thu, 2010-09-30 at 13:16 -0700, Ben Greear wrote:
>> We saw this on a system that has two ath9k APs, some extra routing tables
>> and rules to use them, and a user-space 'bridge' that uses packet-sockets.
>>
>> Aside from a few patches to help virtualize wireless devices (and none directly to ath9k),
>> this is today's wireless-testing tree.
>>
>> =================================
>> [ INFO: inconsistent lock state ]
>> 2.6.36-rc6-wl+ #20
>> ---------------------------------
>> inconsistent {IN-SOFTIRQ-W} ->  {SOFTIRQ-ON-W} usage.
>> kworker/u:0/5 [HC0[0]:SC0[0]:HE1:SE1] takes:
>>    (&(&list->lock)->rlock){+.?...}, at: [<c0741066>] packet_rcv+0x1f3/0x27a
>
> I think this is due to
>
> commit 5ed3bc7288487bd4f891f420a07319e0b538b4fe
> Author: John W. Linville<linville@tuxdriver.com>
> Date:   Thu Jun 24 14:38:30 2010 -0400
>
>      mac80211: use netif_receive_skb in ieee80211_tx_status callpath

Before I go hacking on this, is anyone already working on it?

Thanks,
Ben

>
>
> since
>
> /**
>   *      netif_receive_skb - process receive buffer from network
>   *      @skb: buffer to process
>   *
>   *      netif_receive_skb() is the main receive data processing function.
>   *      It always succeeds. The buffer may be dropped during processing
>   *      for congestion control or by the protocol layers.
>   *
>   *      This function may only be called from softirq context and interrupts
>   *      should be enabled.
>
> but we don't explicitly disable BHs. I suppose we should impose the same
> on drivers calling ieee80211_tx_status().
>
> johannes


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