From: Eric Dumazet <eric.duma...@gmail.com>
Date: Sat, 15 Oct 2016 17:50:49 +0200
> From: Eric Dumazet <eduma...@google.com>
>
> After Jesper commit back in linux-3.18, we trigger a lockdep
> splat in proc_create_data() while allocating memory from
> pktgen_change_name().
>
> This patch converts t->if_lock to a mutex, since it is now only
> used from control path, and adds proper locking to pktgen_change_name()
>
> 1) pktgen_thread_lock to protect the outer loop (iterating threads)
> 2) t->if_lock to protect the inner loop (iterating devices)
>
> Note that before Jesper patch, pktgen_change_name() was lacking proper
> protection, but lockdep was not able to detect the problem.
>
> Fixes: 8788370a1d4b ("pktgen: RCU-ify "if_list" to remove lock in
> next_to_run()")
> Reported-by: John Sperbeck <jsperb...@google.com>
> Signed-off-by: Eric Dumazet <eduma...@google.com>
Applied and queued up for -stable, thanks.
