diff options
author | Jeffy Chen <jeffy.chen@rock-chips.com> | 2017-06-27 17:34:43 +0800 |
---|---|---|
committer | Sasha Levin <alexander.levin@verizon.com> | 2017-10-03 21:36:35 -0400 |
commit | 41be734250169f923cc309e5b77dfa860d42d133 (patch) | |
tree | ff6936b8294afb2e17555a484959ab3e2886b2b6 /net/bluetooth | |
parent | 77735d6c3b8c07961406d24bc4d496d3efb02a20 (diff) |
Bluetooth: cmtp: fix possible might sleep error in cmtp_session
[ Upstream commit f06d977309d09253c744e54e75c5295ecc52b7b4 ]
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>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Diffstat (limited to 'net/bluetooth')
-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 298ed37010e6..3a39fd523e40 100644 --- a/net/bluetooth/cmtp/core.c +++ b/net/bluetooth/cmtp/core.c @@ -281,16 +281,16 @@ 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; @@ -307,9 +307,8 @@ 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); @@ -394,7 +393,7 @@ 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; } @@ -432,7 +431,11 @@ 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; |