rfcomm, sched/wait: Fix broken wait construct (eedf7e47) · Commits · 戴 / test

rfcomm_run() is a tad broken in that is has a nested wait loop. One cannot rely on p->state for the outer wait because the inner wait will overwrite it. Fix this using the new wait_woken() facility. Signed-off-by:

Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Peter Hurley <peter@hurleysoftware.com> Cc: Alexander Holler <holler@ahsoftware.de> Cc: David S. Miller <davem@davemloft.net> Cc: Gustavo Padovan <gustavo@padovan.org> Cc: Joe Perches <joe@perches.com> Cc: Johan Hedberg <johan.hedberg@gmail.com> Cc: Libor Pechacek <lpechacek@suse.cz> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Marcel Holtmann <marcel@holtmann.org> Cc: Seung-Woo Kim <sw0312.kim@samsung.com> Cc: Vignesh Raman <Vignesh_Raman@mentor.com> Cc: linux-bluetooth@vger.kernel.org Cc: netdev@vger.kernel.org Signed-off-by:

Ingo Molnar <mingo@kernel.org>

net/bluetooth/rfcomm/core.c

+8 −10

Original line number	Diff line number	Diff line
		@@ -101,11 +101,11 @@ static struct rfcomm_session rfcomm_session_del(struct rfcomm_session s);
		#define __get_rpn_stop_bits(line) (((line) >> 2) & 0x1)
		#define __get_rpn_parity(line) (((line) >> 3) & 0x7)

		static DECLARE_WAIT_QUEUE_HEAD(rfcomm_wq);

		static void rfcomm_schedule(void)
		{
		if (!rfcomm_thread)
		return;
		wake_up_process(rfcomm_thread);
		wake_up_all(&rfcomm_wq);
		}

		/* ---- RFCOMM FCS computation ---- */
		@@ -2086,24 +2086,22 @@ static void rfcomm_kill_listener(void)

		static int rfcomm_run(void *unused)
		{
		DEFINE_WAIT_FUNC(wait, woken_wake_function);
		BT_DBG("");

		set_user_nice(current, -10);

		rfcomm_add_listener(BDADDR_ANY);

		while (1) {
		set_current_state(TASK_INTERRUPTIBLE);

		if (kthread_should_stop())
		break;
		add_wait_queue(&rfcomm_wq, &wait);
		while (!kthread_should_stop()) {

		/* Process stuff */
		rfcomm_process_sessions();

		schedule();
		wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT);
		}
		__set_current_state(TASK_RUNNING);
		remove_wait_queue(&rfcomm_wq, &wait);

		rfcomm_kill_listener();

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