Re: Question on lockdep and MAX_LOCK_DEPTH

[Steven Rostedt <rostedt@goodmis.org>]

On Wed, 2013-02-06 at 07:56 -0800, Ben Greear wrote:

> > I'm 99% sure that the bug is in your modifications.
> 
> I'm sorry, I tried to make that clear.

You said it was an out of tree module, I didn't realize it had changes
to the core Linux as well.


> My tree is here, minus a few debugging patches related to this bug:
> 
> http://dmz2.candelatech.com/git/gitweb.cgi?p=linux-3.7.dev.y/.git;a=summary

Here's your bug:

3319         list_for_each_entry_rcu(ptype, &ptype_all, list) {
3320                 if (!ptype->dev || ptype->dev == skb->dev) {
3321                         if (pt_prev) {
3322                                 ret = deliver_skb(skb, pt_prev, orig_dev);
3323                                 if (ret == NET_RX_CONSUMED) {
3324                                         kfree_skb(skb); /* we made a copy in deliver_skb */
3325                                         goto out;
3326                                 }
3327                         }

One of many. All those "goto out;"s skip the rcu_read_unlock().

-- Steve