Messages in this thread | | | Subject | Re: [PATCH] lockdep: annotate sk_lock nesting in AF_BLUETOOTH | From | Marcel Holtmann <> | Date | Mon, 30 Oct 2006 09:22:31 +0100 |
| |
Hi Peter,
> ============================================= > [ INFO: possible recursive locking detected ] > 2.6.18-1.2726.fc6 #1 > --------------------------------------------- > hidd/2271 is trying to acquire lock: > (sk_lock-AF_BLUETOOTH){--..}, at: [<f8d16241>] bt_accept_dequeue+0x26/0xc6 > [bluetooth] > > but task is already holding lock: > (sk_lock-AF_BLUETOOTH){--..}, at: [<f8bce088>] l2cap_sock_accept+0x41/0x11e [l2cap] > > other info that might help us debug this: > 1 lock held by hidd/2271: > #0: (sk_lock-AF_BLUETOOTH){--..}, at: [<f8bce088>] > l2cap_sock_accept+0x41/0x11e [l2cap] > > stack backtrace: > [<c04051ed>] show_trace_log_lvl+0x58/0x16a > [<c04057fa>] show_trace+0xd/0x10 > [<c0405913>] dump_stack+0x19/0x1b > [<c043b7dc>] __lock_acquire+0x6ea/0x90d > [<c043bf70>] lock_acquire+0x4b/0x6b > [<c05b203b>] lock_sock+0xac/0xbc > [<f8d16241>] bt_accept_dequeue+0x26/0xc6 [bluetooth] > [<f8bce129>] l2cap_sock_accept+0xe2/0x11e [l2cap] > [<c05b142e>] sys_accept+0xd8/0x179 > [<c05b1576>] sys_socketcall+0xa7/0x186 > [<c0403fb7>] syscall_call+0x7/0xb > > classical case of nesting; bt_accept_dequeue() locks the children of the object > locked by l2cap_sock_accept(). > > Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> > --- > include/net/sock.h | 13 ++++++++++++- > net/bluetooth/l2cap.c | 2 +- > net/core/sock.c | 6 +++--- > 3 files changed, 16 insertions(+), 5 deletions(-) > > Index: linux-2.6/include/net/sock.h > =================================================================== > --- linux-2.6.orig/include/net/sock.h > +++ linux-2.6/include/net/sock.h > @@ -745,7 +745,18 @@ static inline int sk_stream_wmem_schedul > */ > #define sock_owned_by_user(sk) ((sk)->sk_lock.owner) > > -extern void FASTCALL(lock_sock(struct sock *sk)); > +extern void FASTCALL(_lock_sock(struct sock *sk, int subclass)); > + > +static inline void lock_sock(struct sock *sk) > +{ > + _lock_sock(sk, 0); > +} > + > +static inline void lock_sock_nested(struct sock *sk, int subclass) > +{ > + _lock_sock(sk, subclass); > +} > + > extern void FASTCALL(release_sock(struct sock *sk)); > > /* BH context may only use the following locking interface. */ > Index: linux-2.6/net/bluetooth/l2cap.c > =================================================================== > --- linux-2.6.orig/net/bluetooth/l2cap.c > +++ linux-2.6/net/bluetooth/l2cap.c > @@ -770,7 +770,7 @@ static int l2cap_sock_accept(struct sock > long timeo; > int err = 0; > > - lock_sock(sk); > + lock_sock_nested(sk, SINGLE_DEPTH_NESTING); > > if (sk->sk_state != BT_LISTEN) { > err = -EBADFD; > Index: linux-2.6/net/core/sock.c > =================================================================== > --- linux-2.6.orig/net/core/sock.c > +++ linux-2.6/net/core/sock.c > @@ -1527,7 +1527,7 @@ void sock_init_data(struct socket *sock, > atomic_set(&sk->sk_refcnt, 1); > } > > -void fastcall lock_sock(struct sock *sk) > +void fastcall _lock_sock(struct sock *sk, int subclass) > { > might_sleep(); > spin_lock_bh(&sk->sk_lock.slock); > @@ -1538,11 +1538,11 @@ void fastcall lock_sock(struct sock *sk) > /* > * The sk_lock has mutex_lock() semantics here: > */ > - mutex_acquire(&sk->sk_lock.dep_map, 0, 0, _RET_IP_); > + mutex_acquire(&sk->sk_lock.dep_map, subclass, 0, _RET_IP_); > local_bh_enable(); > } > > -EXPORT_SYMBOL(lock_sock); > +EXPORT_SYMBOL(_lock_sock); > > void fastcall release_sock(struct sock *sk) > {
for the Bluetooth subsystem part of this patch:
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Regards
Marcel
- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
| |