[PATCH 0/3] thermal: Fix workqueue-related issues in drivers

[PATCH 0/3] thermal: Fix workqueue-related issues in drivers

[Geert Uytterhoeven]

	Hi,

This patch series fixes workqueue-related issues in the Renesas R-Car
Thermal and Dialog DA9062/9061 PMIC drivers, where the workqueue may run
while the device is suspended, or unbound.
The R-Car Thermal driver fixes have been tested on R-Car M2-W and R-Mobile
APE6.
The DA9062/9061 fixes have been compile-tested only.

Note: The Intel PowerClamp driver also uses schedule_delayed_work(), but I
believe that is OK, as the thermal registers are part of the CPU.

Thanks!

Geert Uytterhoeven (3):
  thermal: rcar_thermal: Prevent hardware access during system suspend
  thermal: rcar_thermal: Prevent doing work after unbind
  thermal: da9062/61: Prevent hardware access during system suspend

 drivers/thermal/da9062-thermal.c | 4 ++--
 drivers/thermal/rcar_thermal.c   | 5 +++--
 2 files changed, 5 insertions(+), 4 deletions(-)

-- 
2.17.1

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds

[PATCH 1/3] thermal: rcar_thermal: Prevent hardware access during system suspend

[Geert Uytterhoeven]

On r8a7791/koelsch, sometimes the following message is printed during
system suspend:

    rcar_thermal e61f0000.thermal: thermal sensor was broken

This happens if the workqueue runs while the device is already
suspended.  Fix this by using the freezable system workqueue instead,
cfr. commit 51e20d0e3a60cf46 ("thermal: Prevent polling from happening
during system suspend").

Fixes: e0a5172e9eec7f0d ("thermal: rcar: add interrupt support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/thermal/rcar_thermal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/rcar_thermal.c b/drivers/thermal/rcar_thermal.c
index 78f932822d381c9d..ea132e122b174757 100644
--- a/drivers/thermal/rcar_thermal.c
+++ b/drivers/thermal/rcar_thermal.c
@@ -434,8 +434,8 @@ static irqreturn_t rcar_thermal_irq(int irq, void *data)
 	rcar_thermal_for_each_priv(priv, common) {
 		if (rcar_thermal_had_changed(priv, status)) {
 			rcar_thermal_irq_disable(priv);
-			schedule_delayed_work(&priv->work,
-					      msecs_to_jiffies(300));
+			queue_delayed_work(system_freezable_wq, &priv->work,
+					   msecs_to_jiffies(300));
 		}
 	}
 
-- 
2.17.1

Re: [PATCH 1/3] thermal: rcar_thermal: Prevent hardware access during system suspend

[Niklas Söderlund]

Hi Geert,

Thanks for your patch.

On 2018-09-27 13:32:33 +0200, Geert Uytterhoeven wrote:
> On r8a7791/koelsch, sometimes the following message is printed during
> system suspend:
> 
>     rcar_thermal e61f0000.thermal: thermal sensor was broken
> 
> This happens if the workqueue runs while the device is already
> suspended.  Fix this by using the freezable system workqueue instead,
> cfr. commit 51e20d0e3a60cf46 ("thermal: Prevent polling from happening
> during system suspend").
> 
> Fixes: e0a5172e9eec7f0d ("thermal: rcar: add interrupt support")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
>  drivers/thermal/rcar_thermal.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/thermal/rcar_thermal.c b/drivers/thermal/rcar_thermal.c
> index 78f932822d381c9d..ea132e122b174757 100644
> --- a/drivers/thermal/rcar_thermal.c
> +++ b/drivers/thermal/rcar_thermal.c
> @@ -434,8 +434,8 @@ static irqreturn_t rcar_thermal_irq(int irq, void *data)
>  	rcar_thermal_for_each_priv(priv, common) {
>  		if (rcar_thermal_had_changed(priv, status)) {
>  			rcar_thermal_irq_disable(priv);
> -			schedule_delayed_work(&priv->work,
> -					      msecs_to_jiffies(300));
> +			queue_delayed_work(system_freezable_wq, &priv->work,
> +					   msecs_to_jiffies(300));
>  		}
>  	}
>  
> -- 
> 2.17.1
> 

-- 
Regards,
Niklas Söderlund

[PATCH 2/3] thermal: rcar_thermal: Prevent doing work after unbind

[Geert Uytterhoeven]

When testing bind/unbind on r8a7791/koelsch:

    WARNING: CPU: 1 PID: 697 at lib/debugobjects.c:329 debug_print_object+0x8c/0xb4
    ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x10

This happens if the workqueue runs after the device has been unbound.
Fix this by cancelling any queued work during remove.

Fixes: e0a5172e9eec7f0d ("thermal: rcar: add interrupt support")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
 drivers/thermal/rcar_thermal.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/thermal/rcar_thermal.c b/drivers/thermal/rcar_thermal.c
index ea132e122b174757..616ba2fccf410d3b 100644
--- a/drivers/thermal/rcar_thermal.c
+++ b/drivers/thermal/rcar_thermal.c
@@ -453,6 +453,7 @@ static int rcar_thermal_remove(struct platform_device *pdev)
 
 	rcar_thermal_for_each_priv(priv, common) {
 		rcar_thermal_irq_disable(priv);
+		cancel_delayed_work_sync(&priv->work);
 		if (priv->chip->use_of_thermal)
 			thermal_remove_hwmon_sysfs(priv->zone);
 		else
-- 
2.17.1

Re: [PATCH 2/3] thermal: rcar_thermal: Prevent doing work after unbind

[Niklas Söderlund]

Hi Geert,

Thanks for your work.

On 2018-09-27 13:32:34 +0200, Geert Uytterhoeven wrote:
> When testing bind/unbind on r8a7791/koelsch:
> 
>     WARNING: CPU: 1 PID: 697 at lib/debugobjects.c:329 debug_print_object+0x8c/0xb4
>     ODEBUG: free active (active state 0) object type: timer_list hint: delayed_work_timer_fn+0x0/0x10
> 
> This happens if the workqueue runs after the device has been unbound.
> Fix this by cancelling any queued work during remove.
> 
> Fixes: e0a5172e9eec7f0d ("thermal: rcar: add interrupt support")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Reviewed-by: Niklas Söderlund <niklas.soderlund+renesas@ragnatech.se>

> ---
>  drivers/thermal/rcar_thermal.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/thermal/rcar_thermal.c b/drivers/thermal/rcar_thermal.c
> index ea132e122b174757..616ba2fccf410d3b 100644
> --- a/drivers/thermal/rcar_thermal.c
> +++ b/drivers/thermal/rcar_thermal.c
> @@ -453,6 +453,7 @@ static int rcar_thermal_remove(struct platform_device *pdev)
>  
>  	rcar_thermal_for_each_priv(priv, common) {
>  		rcar_thermal_irq_disable(priv);
> +		cancel_delayed_work_sync(&priv->work);
>  		if (priv->chip->use_of_thermal)
>  			thermal_remove_hwmon_sysfs(priv->zone);
>  		else
> -- 
> 2.17.1
> 

-- 
Regards,
Niklas Söderlund

[PATCH 3/3] thermal: da9062/61: Prevent hardware access during system suspend

[Geert Uytterhoeven]

The workqueue used for monitoring the hardware may run while the device
is already suspended.  Fix this by using the freezable system workqueue
instead, cfr. commit 51e20d0e3a60cf46 ("thermal: Prevent polling from
happening during system suspend").

Fixes: 608567aac3206ae8 ("thermal: da9062/61: Thermal junction temperature monitoring driver")
Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>
---
Untested due to lack of hardware.
---
 drivers/thermal/da9062-thermal.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/drivers/thermal/da9062-thermal.c b/drivers/thermal/da9062-thermal.c
index dd8dd947b7f0737c..01b0cb9944577851 100644
--- a/drivers/thermal/da9062-thermal.c
+++ b/drivers/thermal/da9062-thermal.c
@@ -106,7 +106,7 @@ static void da9062_thermal_poll_on(struct work_struct *work)
 					   THERMAL_EVENT_UNSPECIFIED);
 
 		delay = msecs_to_jiffies(thermal->zone->passive_delay);
-		schedule_delayed_work(&thermal->work, delay);
+		queue_delayed_work(system_freezable_wq, &thermal->work, delay);
 		return;
 	}
 
@@ -125,7 +125,7 @@ static irqreturn_t da9062_thermal_irq_handler(int irq, void *data)
 	struct da9062_thermal *thermal = data;
 
 	disable_irq_nosync(thermal->irq);
-	schedule_delayed_work(&thermal->work, 0);
+	queue_delayed_work(system_freezable_wq, &thermal->work, 0);
 
 	return IRQ_HANDLED;
 }
-- 
2.17.1