diff options
| author | Peter Hurley <peter@hurleysoftware.com> | 2011-08-05 16:41:35 +0200 |
|---|---|---|
| committer | Gustavo F. Padovan <padovan@profusion.mobi> | 2011-08-12 00:50:27 +0200 |
| commit | 751c10a56802513a6b057c8cf1552cecc1c9afde (patch) | |
| tree | 958b4624a551577f68e0f0e357112637a10c520a | |
| parent | Bluetooth: Don't use cmd_timer to timeout HCI reset command (diff) | |
| download | linux-751c10a56802513a6b057c8cf1552cecc1c9afde.tar.xz linux-751c10a56802513a6b057c8cf1552cecc1c9afde.zip | |
Bluetooth: bnep: Fix deadlock in session deletion
Commit f4d7cd4a4c introduced the usage of kthread API.
kthread_stop is a blocking function which returns only when
the thread exits. In this case, the thread can't exit because it's
waiting for the write lock, which is being held by bnep_del_connection()
which is waiting for the thread to exit -- deadlock.
Use atomic_t/wake_up_process instead to signal to the thread to exit.
Signed-off-by: Jaikumar Ganesh <jaikumar@google.com>
Signed-off-by: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>
| -rw-r--r-- | net/bluetooth/bnep/bnep.h | 1 | ||||
| -rw-r--r-- | net/bluetooth/bnep/core.c | 9 |
2 files changed, 6 insertions, 4 deletions
diff --git a/net/bluetooth/bnep/bnep.h b/net/bluetooth/bnep/bnep.h index 8e6c06158f8e..e7ee5314f39a 100644 --- a/net/bluetooth/bnep/bnep.h +++ b/net/bluetooth/bnep/bnep.h @@ -155,6 +155,7 @@ struct bnep_session { unsigned int role; unsigned long state; unsigned long flags; + atomic_t terminate; struct task_struct *task; struct ethhdr eh; diff --git a/net/bluetooth/bnep/core.c b/net/bluetooth/bnep/core.c index 7e8ff3c24942..d9edfe8bf9d6 100644 --- a/net/bluetooth/bnep/core.c +++ b/net/bluetooth/bnep/core.c @@ -487,7 +487,7 @@ static int bnep_session(void *arg) while (1) { set_current_state(TASK_INTERRUPTIBLE); - if (kthread_should_stop()) + if (atomic_read(&s->terminate)) break; /* RX */ while ((skb = skb_dequeue(&sk->sk_receive_queue))) { @@ -642,9 +642,10 @@ int bnep_del_connection(struct bnep_conndel_req *req) down_read(&bnep_session_sem); s = __bnep_get_session(req->dst); - if (s) - kthread_stop(s->task); - else + if (s) { + atomic_inc(&s->terminate); + wake_up_process(s->task); + } else err = -ENOENT; up_read(&bnep_session_sem); |