thermal: ACPI: Invalidate trip points with temperature of 0 or below

commit 7f18bd49cb upstream.

It is reported that commit 9502108876 ("thermal: core: Drop
trips_disabled bitmask") causes the maximum frequency of CPUs to drop
further down with every system sleep-wake cycle on Intel Core i7-4710HQ.

This turns out to be due to a trip point whose temperature is equal to 0
degrees Celsius which is acted on every time the system wakes from sleep.

Before commit 9502108876 this trip point would be disabled wia the
trips_disabled bitmask, but now it is treated as a valid one.

Since ACPI thermal control is generally about protection against
overheating, trip points with temperature of 0 centigrade or below are
not particularly useful there, so initialize them all as invalid which
fixes the problem at hand.

Fixes: 9502108876 ("thermal: core: Drop trips_disabled bitmask")
Closes: https://lore.kernel.org/linux-pm/3f71747b-f852-4ee0-b384-cf46b2aefa3f@gmx.com
Reported-by: Tibor Billes <tbilles@gmx.com>
Tested-by: Tibor Billes <tbilles@gmx.com>
Cc: 6.7+ <stable@vger.kernel.org> # 6.7+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Rafael J. Wysocki 2024-06-06 20:27:30 +02:00 committed by Greg Kroah-Hartman
parent 6dccf6c052
commit be4b29d992

View file

@ -168,11 +168,17 @@ static int acpi_thermal_get_polling_frequency(struct acpi_thermal *tz)
static int acpi_thermal_temp(struct acpi_thermal *tz, int temp_deci_k)
{
int temp;
if (temp_deci_k == THERMAL_TEMP_INVALID)
return THERMAL_TEMP_INVALID;
return deci_kelvin_to_millicelsius_with_offset(temp_deci_k,
temp = deci_kelvin_to_millicelsius_with_offset(temp_deci_k,
tz->kelvin_offset);
if (temp <= 0)
return THERMAL_TEMP_INVALID;
return temp;
}
static bool acpi_thermal_trip_valid(struct acpi_thermal_trip *acpi_trip)