2023-03-29 15:24:16

by srinivas pandruvada

Subject: [PATCH] thermal: intel: int340x: processor_thermal: Fix additional deadlock

Commit 52f04f10b900 ("thermal: intel: int340x: processor_thermal: Fix
deadlock") addressed deadlock issue during user space trip update. But it
missed a case when thermal zone device is disabled when user writes 0.

Call to thermal_zone_device_disable() also causes deadlock as it also
tries to lock tz->lock, which is already claimed by trip_point_temp_store()
in the thermal core code.

Remove call to thermal_zone_device_disable() in the function
sys_set_trip_temp(), which is called from trip_point_temp_store().

Fixes: 52f04f10b900 ("thermal: intel: int340x: processor_thermal: Fix deadlock")
Signed-off-by: Srinivas Pandruvada <[email protected]>
Cc: [email protected] # 6.2+
---
.../thermal/intel/int340x_thermal/processor_thermal_device_pci.c | 1 -
1 file changed, 1 deletion(-)

diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
index 90526f46c9b1..d71ee50e7878 100644
--- a/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
+++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
@@ -153,7 +153,6 @@ static int sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp
cancel_delayed_work_sync(&pci_info->work);
proc_thermal_mmio_write(pci_info, PROC_THERMAL_MMIO_INT_ENABLE_0, 0);
proc_thermal_mmio_write(pci_info, PROC_THERMAL_MMIO_THRES_0, 0);
- thermal_zone_device_disable(tzd);
pci_info->stored_thres = 0;
return 0;
}
--
2.39.1

2023-03-29 18:40:04

by Rafael J. Wysocki

Subject: Re: [PATCH] thermal: intel: int340x: processor_thermal: Fix additional deadlock

On Wed, Mar 29, 2023 at 5:23 PM Srinivas Pandruvada
<[email protected]> wrote:
>
> Commit 52f04f10b900 ("thermal: intel: int340x: processor_thermal: Fix
> deadlock") addressed deadlock issue during user space trip update. But it
> missed a case when thermal zone device is disabled when user writes 0.
>
> Call to thermal_zone_device_disable() also causes deadlock as it also
> tries to lock tz->lock, which is already claimed by trip_point_temp_store()
> in the thermal core code.
>
> Remove call to thermal_zone_device_disable() in the function
> sys_set_trip_temp(), which is called from trip_point_temp_store().
>
> Fixes: 52f04f10b900 ("thermal: intel: int340x: processor_thermal: Fix deadlock")
> Signed-off-by: Srinivas Pandruvada <[email protected]>
> Cc: [email protected] # 6.2+
> ---
> .../thermal/intel/int340x_thermal/processor_thermal_device_pci.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c b/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
> index 90526f46c9b1..d71ee50e7878 100644
> --- a/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
> +++ b/drivers/thermal/intel/int340x_thermal/processor_thermal_device_pci.c
> @@ -153,7 +153,6 @@ static int sys_set_trip_temp(struct thermal_zone_device *tzd, int trip, int temp
> cancel_delayed_work_sync(&pci_info->work);
> proc_thermal_mmio_write(pci_info, PROC_THERMAL_MMIO_INT_ENABLE_0, 0);
> proc_thermal_mmio_write(pci_info, PROC_THERMAL_MMIO_THRES_0, 0);
> - thermal_zone_device_disable(tzd);
> pci_info->stored_thres = 0;
> return 0;
> }
> --

Applied as 6.3-rc material, thanks!