[PATCH 5.4 14/80] PM / QoS: Redefine FREQ_QOS_MAX_DEFAULT_VALUE to S32_MAX

From: Greg Kroah-Hartman
Date: Thu Dec 19 2019 - 13:59:18 EST


From: Leonard Crestez <leonard.crestez@xxxxxxx>

commit c6a3aea93571a5393602256d8f74772bd64c8225 upstream.

QOS requests for DEFAULT_VALUE are supposed to be ignored but this is
not the case for FREQ_QOS_MAX. Adding one request for MAX_DEFAULT_VALUE
and one for a real value will cause freq_qos_read_value to unexpectedly
return MAX_DEFAULT_VALUE (-1).

This happens because freq_qos max value is aggregated with PM_QOS_MIN
but FREQ_QOS_MAX_DEFAULT_VALUE is (-1) so it's smaller than other
values.

Fix this by redefining FREQ_QOS_MAX_DEFAULT_VALUE to S32_MAX.

Looking at current users for freq_qos it seems that none of them create
requests for FREQ_QOS_MAX_DEFAULT_VALUE.

Fixes: 77751a466ebd ("PM: QoS: Introduce frequency QoS")
Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>
Reported-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Reviewed-by: Matthias Kaehlcke <mka@xxxxxxxxxxxx>
Cc: 5.4+ <stable@xxxxxxxxxxxxxxx> # 5.4+
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
include/linux/pm_qos.h | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

--- a/include/linux/pm_qos.h
+++ b/include/linux/pm_qos.h
@@ -256,7 +256,7 @@ static inline s32 dev_pm_qos_raw_resume_
#endif

#define FREQ_QOS_MIN_DEFAULT_VALUE 0
-#define FREQ_QOS_MAX_DEFAULT_VALUE (-1)
+#define FREQ_QOS_MAX_DEFAULT_VALUE S32_MAX

enum freq_qos_req_type {
FREQ_QOS_MIN = 1,