On Wednesday, May 31, 2006 at 13:26 +0200, Martin Röhricht wrote: > But thanks for your reply. Any more help is appreciated and welcome. I may have located the trouble maker, but I am still unsure how to solve it. My current l2cap.c and l2cap.h can be found here: http://studwww.ira.uka.de/~s_roehr/ The original source handles a successful connection request in l2cap_connect_rsp() by the following lines to issue a configuration request: case L2CAP_CR_SUCCESS: sk->sk_state = BT_CONFIG; l2cap_pi(sk)->ident = 0; l2cap_pi(sk)->dcid = dcid; l2cap_pi(sk)->conf_state |= L2CAP_CONF_REQ_SENT; l2cap_send_cmd(conn, l2cap_get_ident(conn), L2CAP_CONF_REQ, l2cap_build_conf_req(sk, req), req); break; I need to issue an information request first and since a hardcoded ident of 0 doesn't work with each device, I rewrote this part as follows: case L2CAP_CR_SUCCESS: sk->sk_state = BT_CONFIG; l2cap_pi(sk)->ident = l2cap_get_ident(conn); l2cap_pi(sk)->dcid = dcid; /* send information request first */ l2cap_pi(sk)->conf_state |= L2CAP_INFO_REQ_SENT; l2cap_send_cmd(conn, l2cap_pi(sk)->ident, L2CAP_INFO_REQ, l2cap_build_info_req(&info), &info); break; Now I did some testing on this part. I know that one of my devices (a mobile phone) expects »2« as the initial ident after the connection establishement. In case I write l2cap_pi(sk)->ident = 2; and pass this l2cap_pi(sk)->ident into the l2cap_send_cmd() function, I get the deadlock again. But in case I don't use the above and write »2« directly into l2cap_send_cmd() I don't get a deadlock anymore (unfortunately this is hardcoded for just one device and the control flow doesn't continue after an information response). So there must be some locking issues that I do not get handled yet properly. The logic seems to be fine as it works on a single processor with a non-preemptable kernel. Rafał, do you see the problem? It might have something to do with the »bh_unlock_sock(sk);« that comes into play after the switch statement. Thanks a lot for any help, Martin -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
