| Message ID | 20230123172110.376549-1-srinivas.pandruvada@linux.intel.com |
|---|---|
| State | New |
| Headers | show |
| Series | [v2] thermal: int340x: Protect trip temperature from dynamic update | expand |
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 > >
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 *,
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 - Add ret variable and remove return as suugested by Rafael .../int340x_thermal/int340x_thermal_zone.c | 18 +++++++++++++++--- .../int340x_thermal/int340x_thermal_zone.h | 1 + 2 files changed, 16 insertions(+), 3 deletions(-)