From 7f18bd49cb6b6a3ab6d860fefccdc94f2a247db0 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 6 Jun 2024 20:27:30 +0200 Subject: [PATCH] thermal: ACPI: Invalidate trip points with temperature of 0 or below It is reported that commit 950210887670 ("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 950210887670 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: 950210887670 ("thermal: core: Drop trips_disabled bitmask") Closes: https://lore.kernel.org/linux-pm/3f71747b-f852-4ee0-b384-cf46b2aefa3f@gmx.com Reported-by: Tibor Billes Tested-by: Tibor Billes Cc: 6.7+ # 6.7+ Signed-off-by: Rafael J. Wysocki --- drivers/acpi/thermal.c | 8 +++++++- 1 file changed, 7 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/thermal.c b/drivers/acpi/thermal.c index d67881b50bca..a0cfc857fb55 100644 --- a/drivers/acpi/thermal.c +++ b/drivers/acpi/thermal.c @@ -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)