Re: RCU'ed dst_get_neighbour()

Eric Dumazet
2011-11-29T23:11:01Z

Le mardi 29 novembre 2011 à 16:03 -0700, Marc Aurele La France a écrit :

> No, only warnings (splats as you call them) would be produced. The fact
> is you added side-effects to dst_get_neighbour(), and I would expect all
> its invocations to be affected.
>

A splat _is_ a bad thing.

We certainly have some bugs, but I sent an infiniband patch, not a
'change the world' one ;)

Most of the network stack is run under rcu_read_lock() already.

If you notice other lockdep splats, please shout :)

Some changes are needed now rcu_read_lock_bh() doesnt imply
rcu_read_lock().

For example, recently added skb_update_prio() is buggy, since it uses
rcu_dereference() while its caller, dev_queue_xmit() called
rcu_read_lock_bh()