Commit 2f9b5b3a authored by Kuogee Hsieh's avatar Kuogee Hsieh Committed by Dmitry Baryshkov
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drm/msm/dp: fix event thread stuck in wait_event after kthread_stop() 



Event thread supposed to exit from its while loop after kthread_stop().
However there may has possibility that event thread is pending in the
middle of wait_event due to condition checking never become true.
To make sure event thread exit its loop after kthread_stop(), this
patch OR kthread_should_stop() into wait_event's condition checking
so that event thread will exit its loop after kernal_stop().

Changes in v2:
--  correct spelling error at commit title

Changes in v3:
-- remove unnecessary parenthesis
-- while(1) to replace while (!kthread_should_stop())

Reported-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Fixes: 570d3e5d ("drm/msm/dp: stop event kernel thread when DP unbind")
Signed-off-by: default avatarKuogee Hsieh <quic_khsieh@quicinc.com>
Reviewed-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
Reviewed-by: default avatarStephen Boyd <swboyd@chromium.org>
Patchwork: https://patchwork.freedesktop.org/patch/484576/
Link: https://lore.kernel.org/r/1651595136-24312-1-git-send-email-quic_khsieh@quicinc.com


Signed-off-by: default avatarDmitry Baryshkov <dmitry.baryshkov@linaro.org>
parent 9208c707

drivers/gpu/drm/msm/dp/dp_display.c

+9 −4
Original line number Diff line number Diff line
@@ -1103,15 +1103,20 @@ static int hpd_event_thread(void *data) 


	dp_priv = (struct dp_display_private *)data;



	while (!kthread_should_stop()) {

	while (1) {

		if (timeout_mode) {

			wait_event_timeout(dp_priv->event_q,

				(dp_priv->event_pndx == dp_priv->event_gndx),

						EVENT_TIMEOUT);

				(dp_priv->event_pndx == dp_priv->event_gndx) ||

					kthread_should_stop(), EVENT_TIMEOUT);

		} else {

			wait_event_interruptible(dp_priv->event_q,

				(dp_priv->event_pndx != dp_priv->event_gndx));

				(dp_priv->event_pndx != dp_priv->event_gndx) ||

					kthread_should_stop());

		}



		if (kthread_should_stop())

			break;



		spin_lock_irqsave(&dp_priv->event_lock, flag);

		todo = &dp_priv->event_list[dp_priv->event_gndx];

		if (todo->delay) {