Re: [PATCH] thermal: int340x: processor_thermal: Fix deadlock

From: Greg KH
Date: Fri Mar 03 2023 - 13:52:39 EST


On Fri, Mar 03, 2023 at 08:19:09AM -0800, Srinivas Pandruvada wrote:
> From: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxx>
>
> When user space updates the trip point there is a deadlock, which results
> in caller gets blocked forever.
>
> Commit 05eeee2b51b4 ("thermal/core: Protect sysfs accesses to thermal
> operations with thermal zone mutex"), added a mutex for tz->lock in the
> function trip_point_temp_store(). Hence, trip set callback() can't
> call any thermal zone API as they are protected with the same mutex lock.
>
> The callback here calling thermal_zone_device_enable(), which will result
> in deadlock.
>
> Move the thermal_zone_device_enable() to proc_thermal_pci_probe() to
> avoid this deadlock.
>
> Signed-off-by: Srinivas Pandruvada <srinivas.pandruvada@xxxxxxxxx>
> Cc: stable@xxxxxxxxxxxxxxx
> ---
> The commit which caused this issue was added during v6.2 cycle.

What commit exactly? Always list that as a Fixes: tag if you know this.

thanks,

greg k-h