On Fri, 2016-04-01 at 03:36 +0200, Hannes Frederic Sowa wrote: > On Fri, Apr 1, 2016, at 03:19, Eric Dumazet wrote: > > Thanks. > > > > As you can see, release_sock() messes badly lockdep (once your other > > patches are in ) > > > > Once we properly fix release_sock() and/or __release_sock(), all these > > false positives disappear. > > This was a loopback connection. I need to study release_sock and > __release_sock more as I cannot currently see an issue with the lockdep > handling.
Okay, please try : diff --git a/net/core/sock.c b/net/core/sock.c index b67b9aedb230..570dcd91d64e 100644 --- a/net/core/sock.c +++ b/net/core/sock.c @@ -2429,10 +2429,6 @@ EXPORT_SYMBOL(lock_sock_nested); void release_sock(struct sock *sk) { - /* - * The sk_lock has mutex_unlock() semantics: - */ - mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); spin_lock_bh(&sk->sk_lock.slock); if (sk->sk_backlog.tail) @@ -2445,6 +2441,10 @@ void release_sock(struct sock *sk) sk->sk_prot->release_cb(sk); sock_release_ownership(sk); + /* + * The sk_lock has mutex_unlock() semantics: + */ + mutex_release(&sk->sk_lock.dep_map, 1, _RET_IP_); if (waitqueue_active(&sk->sk_lock.wq)) wake_up(&sk->sk_lock.wq); spin_unlock_bh(&sk->sk_lock.slock);