[PATCH] int340X/processor_thermal_device: Fix proc_thermal_rapl_remove()

From: Rafael J. Wysocki
Date: Mon Jul 22 2019 - 06:23:02 EST


From: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>

Passing 0 to cpuhp_remove_state() triggers the BUG_ON() in
__cpuhp_remove_state_cpuslocked() and the argument passed to
powercap_unregister_control_type() is expected to be a valid
pointer, so avoid calling these functions with incorrect
arguments from proc_thermal_rapl_remove().

Fixes: 555c45fe0d04 ("int340X/processor_thermal_device: add support for MMIO RAPL")
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
---
drivers/thermal/intel/int340x_thermal/processor_thermal_device.c | 4 ++++
1 file changed, 4 insertions(+)

Index: linux-pm/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
===================================================================
--- linux-pm.orig/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
+++ linux-pm/drivers/thermal/intel/int340x_thermal/processor_thermal_device.c
@@ -487,6 +487,7 @@ static int proc_thermal_rapl_add(struct
rapl_mmio_cpu_online, rapl_mmio_cpu_down_prep);
if (ret < 0) {
powercap_unregister_control_type(rapl_mmio_priv.control_type);
+ rapl_mmio_priv.control_type = NULL;
return ret;
}
rapl_mmio_priv.pcap_rapl_online = ret;
@@ -496,6 +497,9 @@ static int proc_thermal_rapl_add(struct

static void proc_thermal_rapl_remove(void)
{
+ if (IS_ERR_OR_NULL(rapl_mmio_priv.control_type))
+ return;
+
cpuhp_remove_state(rapl_mmio_priv.pcap_rapl_online);
powercap_unregister_control_type(rapl_mmio_priv.control_type);
}