Subject: Re: [3.4-rc1][Regression][network wireless] 'task xxxx blocked for more than 120 seconds' after resume

From: Stanislaw Gruszka <[email-masked]>
Date: Thu, 5 Apr 2012 12:32:54 +0200

On Tue, Apr 03, 2012 at 10:07:49AM +0200, Johannes Berg wrote:
> -ilw
> +netdev
> 
> I have no idea what this could be, but I'm almost certain it's not
> caused by our wireless driver. Looks more like rtl8169 is to blame.

I'm not sure. Looks like there is deadlock or infinite loop in process
that holds rtnl lock. This can be wireless driver, wired driver or
generic network code bug.

Maciej, please recompile with CONFIG_LOCKDEP and check if it will not
find any deadlock. If not, when problem will happen please do

echo w > /proc/sysrq-trigger
dmesg -c > dmesg1.txt
echo t > /proc/sysrq-trigger
dmesg > dmesg2.txt

and provide those files.

Additionally there are also lot in dmesg:

 netlink: 140 bytes leftover after parsing attributes.

This need to be investigated as well. Perhaps you could modify error
message, to show what netlink messages/attributes are processed.

Thanks
Stanislaw