On Tue, 2023-01-24 at 21:32 +0100, Rafael J. Wysocki wrote:
On Mon, Jan 23, 2023 at 6:26 PM Srinivas Pandruvada srinivas.pandruvada@linux.intel.com wrote:
Trip temperatures are read using ACPI methods and stored in the memory during zone initializtion and when the firmware sends a notification for change. This trip temperature is returned when the thermal core calls via callback get_trip_temp().
But it is possible that while updating the memory copy of the trips when the firmware sends a notification for change, thermal core is reading the trip temperature via the callback get_trip_temp(). This may return invalid trip temperature.
To address this add a mutex to protect the invalid temperature reads in the callback get_trip_temp() and int340x_thermal_read_trips().
Signed-off-by: Srinivas Pandruvada srinivas.pandruvada@linux.intel.com Cc: stable@vger.kernel.org # 5.0+
v2:
- rebased on linux-next
So I've rebased it back onto 6.2-rc5 and pushed the result into the thermal-intel-fixes branch. Please see if it looks good to you and let me know.
Looks good.
Thanks, Srinivas
I'd prefer to push it for 6.2-rc.
- Add ret variable and remove return as suugested by Rafael
Thanks!
.../int340x_thermal/int340x_thermal_zone.c | 18 +++++++++++++++--- .../int340x_thermal/int340x_thermal_zone.h | 1 + 2 files changed, 16 insertions(+), 3 deletions(-)
diff --git a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c index 228f44260b27..5fda1e67b793 100644 --- a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c +++ b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.c @@ -41,7 +41,9 @@ static int int340x_thermal_get_trip_temp(struct thermal_zone_device *zone, int trip, int *temp) { struct int34x_thermal_zone *d = zone->devdata; - int i; + int i, ret = 0;
+ mutex_lock(&d->trip_mutex);
if (trip < d->aux_trip_nr) *temp = d->aux_trips[trip]; @@ -60,10 +62,12 @@ static int int340x_thermal_get_trip_temp(struct thermal_zone_device *zone, } } if (i == INT340X_THERMAL_MAX_ACT_TRIP_COUNT) - return -EINVAL; + ret = -EINVAL; }
- return 0; + mutex_unlock(&d->trip_mutex);
+ return ret; }
static int int340x_thermal_get_trip_type(struct thermal_zone_device *zone, @@ -165,6 +169,8 @@ int int340x_thermal_read_trips(struct int34x_thermal_zone *int34x_zone) int trip_cnt = int34x_zone->aux_trip_nr; int i;
+ mutex_lock(&int34x_zone->trip_mutex);
int34x_zone->crt_trip_id = -1; if (!int340x_thermal_get_trip_config(int34x_zone->adev-
handle, "_CRT",
&int34x_zone-
crt_temp))
@@ -192,6 +198,8 @@ int int340x_thermal_read_trips(struct int34x_thermal_zone *int34x_zone) int34x_zone->act_trips[i].valid = true; }
+ mutex_unlock(&int34x_zone->trip_mutex);
return trip_cnt; } EXPORT_SYMBOL_GPL(int340x_thermal_read_trips); @@ -215,6 +223,8 @@ struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *adev, if (!int34x_thermal_zone) return ERR_PTR(-ENOMEM);
+ mutex_init(&int34x_thermal_zone->trip_mutex);
int34x_thermal_zone->adev = adev;
int34x_thermal_zone->ops = kmemdup(&int340x_thermal_zone_ops, @@ -277,6 +287,7 @@ struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *adev, err_trip_alloc: kfree(int34x_thermal_zone->ops); err_ops_alloc: + mutex_destroy(&int34x_thermal_zone->trip_mutex); kfree(int34x_thermal_zone); return ERR_PTR(ret); } @@ -289,6 +300,7 @@ void int340x_thermal_zone_remove(struct int34x_thermal_zone acpi_lpat_free_conversion_table(int34x_thermal_zone-
lpat_table);
kfree(int34x_thermal_zone->aux_trips); kfree(int34x_thermal_zone->ops); + mutex_destroy(&int34x_thermal_zone->trip_mutex); kfree(int34x_thermal_zone); } EXPORT_SYMBOL_GPL(int340x_thermal_zone_remove); diff --git a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h index e28ab1ba5e06..6610a9cc441b 100644 --- a/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h +++ b/drivers/thermal/intel/int340x_thermal/int340x_thermal_zone.h @@ -32,6 +32,7 @@ struct int34x_thermal_zone { struct thermal_zone_device_ops *ops; void *priv_data; struct acpi_lpat_conversion_table *lpat_table; + struct mutex trip_mutex; };
struct int34x_thermal_zone *int340x_thermal_zone_add(struct acpi_device *, -- 2.31.1