On kernels build with CONFIG_PROVE_LOCKING, CONFIG_MODULES and CONFIG_DEBUG_LOCK_ALLOC 'rmmod rdma_rxe' is no longer possible. For the global recv sockets rxe_net_exit() is where we call rxe_release_udp_tunnel-> udp_tunnel_sock_release(), which means the sockets are destroyed before 'rmmod rdma_rxe' finishes, so there's no need to protect against rxe_recv_slock_key and rxe_recv_sk_key disappearing while the sockets are still alive. Fixes: 80a85a771deb ("RDMA/rxe: reclassify sockets in order to avoid false positives from lockdep") Cc: Zhu Yanjun Cc: Jason Gunthorpe Cc: Leon Romanovsky Cc: Shinichiro Kawasaki Cc: linux-rdma@vger.kernel.org Cc: netdev@vger.kernel.org Cc: linux-cifs@vger.kernel.org Signed-off-by: Stefan Metzmacher --- drivers/infiniband/sw/rxe/rxe_net.c | 32 +++++++++++++++++++++++++++++ 1 file changed, 32 insertions(+) diff --git a/drivers/infiniband/sw/rxe/rxe_net.c b/drivers/infiniband/sw/rxe/rxe_net.c index 0195d361e5e3..0bd0902b11f7 100644 --- a/drivers/infiniband/sw/rxe/rxe_net.c +++ b/drivers/infiniband/sw/rxe/rxe_net.c @@ -64,7 +64,39 @@ static inline void rxe_reclassify_recv_socket(struct socket *sock) break; default: WARN_ON_ONCE(1); + return; } + /* + * sock_lock_init_class_and_name() calls + * sk_owner_set(sk, THIS_MODULE); in order + * to make sure the referenced global + * variables rxe_recv_slock_key and + * rxe_recv_sk_key are not removed + * before the socket is closed. + * + * However this prevents rxe_net_exit() + * from being called and 'rmmod rdma_rxe' + * is refused because of the references. + * + * For the global sockets in recv_sockets, + * we are sure that rxe_net_exit() will call + * rxe_release_udp_tunnel -> udp_tunnel_sock_release. + * + * So we don't need the additional reference to + * our own (THIS_MODULE). + */ + sk_owner_put(sk); + /* + * We also call sk_owner_clear() otherwise + * sk_owner_put(sk) in sk_prot_free will + * fail, which is called via + * sk_free -> __sk_free -> sk_destruct + * and sk_destruct calls __sk_destruct + * directly or via call_rcu() + * so sk_prot_free() might be called + * after rxe_net_exit(). + */ + sk_owner_clear(sk); #endif /* CONFIG_DEBUG_LOCK_ALLOC */ } -- 2.43.0