[PATCH 3/3] thermal: core: register a crash callback

From: Eduardo Valentin
Date: Thu May 25 2023 - 17:17:27 EST


From: Eduardo Valentin <eduval@xxxxxxxxxx>

This commit will register a crash callback for
the thermal subsystem, this way the thermal
core can tear down the thermal zones and ask
governors to leave the hardware in a known
safe state prior upon the event of a crash.

Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> (supporter:THERMAL)
Cc: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx> (supporter:THERMAL)
Cc: Amit Kucheria <amitk@xxxxxxxxxx> (reviewer:THERMAL)
Cc: Zhang Rui <rui.zhang@xxxxxxxxx> (reviewer:THERMAL)
Cc: Jonathan Corbet <corbet@xxxxxxx> (maintainer:DOCUMENTATION)
Cc: linux-pm@xxxxxxxxxxxxxxx (open list:THERMAL)
Cc: linux-doc@xxxxxxxxxxxxxxx (open list:DOCUMENTATION)
Cc: linux-kernel@xxxxxxxxxxxxxxx (open list)

Signed-off-by: Eduardo Valentin <eduval@xxxxxxxxxx>
---
drivers/thermal/thermal_core.c | 15 +++++++++++++++
1 file changed, 15 insertions(+)

diff --git a/drivers/thermal/thermal_core.c b/drivers/thermal/thermal_core.c
index 66a255fb650b..38b168b9245e 100644
--- a/drivers/thermal/thermal_core.c
+++ b/drivers/thermal/thermal_core.c
@@ -20,6 +20,7 @@
#include <linux/string.h>
#include <linux/of.h>
#include <linux/suspend.h>
+#include <linux/panic_notifier.h>

#define CREATE_TRACE_POINTS
#include "thermal_trace.h"
@@ -1525,6 +1526,14 @@ static void thermal_reboot_prepare(void)
}
}

+static int thermal_crash_notify(struct notifier_block *nb,
+ unsigned long mode, void *_unused)
+{
+ thermal_reboot_prepare();
+
+ return 0;
+}
+
static int thermal_reboot_notify(struct notifier_block *nb,
unsigned long mode, void *_unused)
{
@@ -1569,6 +1578,10 @@ static struct notifier_block thermal_pm_nb = {
.notifier_call = thermal_pm_notify,
};

+static struct notifier_block thermal_crash_nb = {
+ .notifier_call = thermal_crash_notify,
+};
+
static struct notifier_block thermal_reboot_nb = {
.notifier_call = thermal_reboot_notify,
};
@@ -1611,6 +1624,8 @@ static int __init thermal_init(void)
pr_warn("Thermal: Can not register reboot notifier, return %d\n",
result);

+ atomic_notifier_chain_register(&panic_notifier_list,
+ &thermal_crash_nb);
return 0;

unregister_governors:
--
2.34.1