There are three kind of issues:
1> There are two resource leak issues in acpi_processor_power_init:
a> Don't unregister acpi_idle_driver when do kzalloc failed.
b> Don't free cpuidle device memory when register cpuidle device failed.
2> There isn't lock to prevent the global acpi_processor_registered, which
may lead to concurrent register cpuidle driver.
3> The cpuidle driver should be registered in advance when all of the CPUs
have been brought up instead of being in a CPU hotplug callback.
To solve these issues, so add a new function to initialize acpi_idle_driver
based on the power management information of an available CPU and register
cpuidle driver in acpi_processor_driver_init().
Signed-off-by: Huisong Li <lihuisong@xxxxxxxxxx>
---
v2: register cpuidle driver in advance when all of the CPUs have been
brought up.
v1 link: https://patchwork.kernel.org/project/linux-acpi/patch/20250619061327.1674384-1-lihuisong@xxxxxxxxxx/
---
drivers/acpi/processor_driver.c | 5 +++
drivers/acpi/processor_idle.c | 71 ++++++++++++++++++++++-----------
include/acpi/processor.h | 9 +++++
3 files changed, 62 insertions(+), 23 deletions(-)
diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c
index 65e779be64ff..ff944c93b6ff 100644
--- a/drivers/acpi/processor_driver.c
+++ b/drivers/acpi/processor_driver.c
@@ -263,6 +263,10 @@ static int __init acpi_processor_driver_init(void)
if (result < 0)
return result;
+ result = acpi_processor_register_idle_driver();
+ if (result)
+ pr_info("register idle driver failed, ret = %d.\n", result);
+
result = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN,
"acpi/cpu-drv:online",
acpi_soft_cpu_online, NULL);
@@ -301,6 +305,7 @@ static void __exit acpi_processor_driver_exit(void)
cpuhp_remove_state_nocalls(hp_online);
cpuhp_remove_state_nocalls(CPUHP_ACPI_CPUDRV_DEAD);
+ acpi_processor_unregister_idle_driver();
driver_unregister(&acpi_processor_driver);
}
diff --git a/drivers/acpi/processor_idle.c b/drivers/acpi/processor_idle.c
index 2c2dc559e0f8..2408f1076631 100644
--- a/drivers/acpi/processor_idle.c
+++ b/drivers/acpi/processor_idle.c
@@ -1360,7 +1360,52 @@ int acpi_processor_power_state_has_changed(struct acpi_processor *pr)
return 0;
}
-static int acpi_processor_registered;
+int acpi_processor_register_idle_driver(void)
+{
+ struct acpi_processor *pr;
+ int cpu;
+ int ret;
+
+ /*
+ * Acpi idle driver is used by all possible CPUs.
+ * Install the idle handler by the processor power info of one in them.
+ * Note that we use previously set idle handler will be used on
+ * platforms that only support C1.
+ */
+ for_each_cpu(cpu, (struct cpumask *)cpu_possible_mask) {
+ pr = per_cpu(processors, cpu);
+ if (pr == NULL)
+ continue;
+
+ ret = acpi_processor_get_power_info(pr);
+ if (!ret) {
+ pr->flags.power_setup_done = 1;
+ break;
+ }
+ }
+
+ if (unlikely(!pr))
+ return -ENODEV;
+
+ if (ret) {
+ pr_err("%s get power information failed.\n",
+ acpi_idle_driver.name);
+ return ret;
+ }
+
+ acpi_processor_setup_cpuidle_states(pr);
+ ret = cpuidle_register_driver(&acpi_idle_driver);
+ if (ret)
+ return ret;
+
+ pr_debug("%s registered with cpuidle\n", acpi_idle_driver.name);
+ return 0;
+}
+
+void acpi_processor_unregister_idle_driver(void)
+{
+ cpuidle_unregister_driver(&acpi_idle_driver);
+}
int acpi_processor_power_init(struct acpi_processor *pr)
{
@@ -1375,22 +1420,7 @@ int acpi_processor_power_init(struct acpi_processor *pr)
if (!acpi_processor_get_power_info(pr))
pr->flags.power_setup_done = 1;
- /*
- * Install the idle handler if processor power management is supported.
- * Note that we use previously set idle handler will be used on
- * platforms that only support C1.
- */
if (pr->flags.power) {
- /* Register acpi_idle_driver if not already registered */
- if (!acpi_processor_registered) {
- acpi_processor_setup_cpuidle_states(pr);
- retval = cpuidle_register_driver(&acpi_idle_driver);
- if (retval)
- return retval;
- pr_debug("%s registered with cpuidle\n",
- acpi_idle_driver.name);
- }
-
dev = kzalloc(sizeof(*dev), GFP_KERNEL);
if (!dev)
return -ENOMEM;
@@ -1403,11 +1433,10 @@ int acpi_processor_power_init(struct acpi_processor *pr)
*/
retval = cpuidle_register_device(dev);
if (retval) {
- if (acpi_processor_registered == 0)
- cpuidle_unregister_driver(&acpi_idle_driver);
+ per_cpu(acpi_cpuidle_device, pr->id) = NULL;
+ kfree(dev);
return retval;
}
- acpi_processor_registered++;
}
return 0;
}
@@ -1421,10 +1450,6 @@ int acpi_processor_power_exit(struct acpi_processor *pr)
if (pr->flags.power) {
cpuidle_unregister_device(dev);
- acpi_processor_registered--;
- if (acpi_processor_registered == 0)
- cpuidle_unregister_driver(&acpi_idle_driver);
-
kfree(dev);
}
diff --git a/include/acpi/processor.h b/include/acpi/processor.h
index d0eccbd920e5..3cb41a3f2d9a 100644
--- a/include/acpi/processor.h
+++ b/include/acpi/processor.h
@@ -423,6 +423,8 @@ int acpi_processor_power_init(struct acpi_processor *pr);
int acpi_processor_power_exit(struct acpi_processor *pr);
int acpi_processor_power_state_has_changed(struct acpi_processor *pr);
int acpi_processor_hotplug(struct acpi_processor *pr);
+int acpi_processor_register_idle_driver(void);
+void acpi_processor_unregister_idle_driver(void);
#else
static inline int acpi_processor_power_init(struct acpi_processor *pr)
{
@@ -443,6 +445,13 @@ static inline int acpi_processor_hotplug(struct acpi_processor *pr)
{
return -ENODEV;
}
+static int acpi_processor_register_idle_driver(void)
+{
+ return -ENODEV;
+}
+static void acpi_processor_unregister_idle_driver(void)
+{
+}
#endif /* CONFIG_ACPI_PROCESSOR_IDLE */
/* in processor_thermal.c */
--
2.33.0
