diff options
| author | Jeffy Chen <jeffy.chen@rock-chips.com> | 2017-06-27 12:34:43 +0300 |
|---|---|---|
| committer | Marcel Holtmann <marcel@holtmann.org> | 2017-06-27 20:32:11 +0300 |
| commit | f06d977309d09253c744e54e75c5295ecc52b7b4 (patch) | |
| tree | 530a02fc18a3983e4fd42641844ae7492fe9db5c | |
| parent | 25717382c1dd0ddced2059053e3ca5088665f7a5 (diff) | |
| download | linux-f06d977309d09253c744e54e75c5295ecc52b7b4.tar.xz | |
Bluetooth: cmtp: fix possible might sleep error in cmtp_session
It looks like cmtp_session has same pattern as the issue reported in
old rfcomm:
while (1) {
set_current_state(TASK_INTERRUPTIBLE);
if (condition)
break;
// may call might_sleep here
schedule();
}
__set_current_state(TASK_RUNNING);
Which fixed at:
dfb2fae Bluetooth: Fix nested sleeps
So let's fix it at the same way, also follow the suggestion of:
https://lwn.net/Articles/628628/
Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com>
Reviewed-by: Brian Norris <briannorris@chromium.org>
Reviewed-by: AL Yu-Chen Cho <acho@suse.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
| -rw-r--r-- | net/bluetooth/cmtp/core.c | 17 |
1 files changed, 10 insertions, 7 deletions
diff --git a/net/bluetooth/cmtp/core.c b/net/bluetooth/cmtp/core.c index f4c64ef01c24..7f26a5a19ff6 100644 --- a/net/bluetooth/cmtp/core.c +++ b/net/bluetooth/cmtp/core.c @@ -280,16 +280,16 @@ static int cmtp_session(void *arg) struct cmtp_session *session = arg; struct sock *sk = session->sock->sk; struct sk_buff *skb; - wait_queue_t wait; + DEFINE_WAIT_FUNC(wait, woken_wake_function); BT_DBG("session %p", session); set_user_nice(current, -15); - init_waitqueue_entry(&wait, current); add_wait_queue(sk_sleep(sk), &wait); while (1) { - set_current_state(TASK_INTERRUPTIBLE); + /* Ensure session->terminate is updated */ + smp_mb__before_atomic(); if (atomic_read(&session->terminate)) break; @@ -306,9 +306,8 @@ static int cmtp_session(void *arg) cmtp_process_transmit(session); - schedule(); + wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); } - __set_current_state(TASK_RUNNING); remove_wait_queue(sk_sleep(sk), &wait); down_write(&cmtp_session_sem); @@ -393,7 +392,7 @@ int cmtp_add_connection(struct cmtp_connadd_req *req, struct socket *sock) err = cmtp_attach_device(session); if (err < 0) { atomic_inc(&session->terminate); - wake_up_process(session->task); + wake_up_interruptible(sk_sleep(session->sock->sk)); up_write(&cmtp_session_sem); return err; } @@ -431,7 +430,11 @@ int cmtp_del_connection(struct cmtp_conndel_req *req) /* Stop session thread */ atomic_inc(&session->terminate); - wake_up_process(session->task); + + /* Ensure session->terminate is updated */ + smp_mb__after_atomic(); + + wake_up_interruptible(sk_sleep(session->sock->sk)); } else err = -ENOENT; |