[PATCH] ACPI / battery: safe unregistering of hooks

Jouke Witteveen
2018-06-23T09:08:51Z

As unregistering a hook takes it off the hook list, we should use a safe
for_each loop when we potentially unregister a hook.

Signed-off-by: Jouke Witteveen <j.witteveen-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
---
drivers/acpi/battery.c | 9 +++++----
1 file changed, 5 insertions(+), 4 deletions(-)

diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
index b0113a58..d79ad844 100644
--- a/drivers/acpi/battery.c
+++ b/drivers/acpi/battery.c
@@ -717,10 +717,11 @@ void battery_hook_register(struct acpi_battery_hook *hook)
*/
pr_err("extension failed to load: %s", hook->name);
__battery_hook_unregister(hook, 0);
- return;
+ goto end;
}
}
pr_info("new extension: %s\n", hook->name);
+end:
mutex_unlock(&hook_mutex);
}
EXPORT_SYMBOL_GPL(battery_hook_register);
@@ -732,7 +733,7 @@ EXPORT_SYMBOL_GPL(battery_hook_register);
*/
static void battery_hook_add_battery(struct acpi_battery *battery)
{
- struct acpi_battery_hook *hook_node;
+ struct acpi_battery_hook *hook_node, *tmp;

mutex_lock(&hook_mutex);
INIT_LIST_HEAD(&battery->list);
@@ -744,15 +745,15 @@ static void battery_hook_add_battery(struct acpi_battery *battery)
* when a battery gets hotplugged or initialized
* during the battery module initialization.
*/
- list_for_each_entry(hook_node, &battery_hook_list, list) {
+ list_for_each_entry_safe(hook_node, tmp, &battery_hook_list, list) {
if (hook_node->add_battery(battery->bat)) {
/*
* The notification of the extensions has failed, to
* prevent further errors we will unload the extension.
*/
- __battery_hook_unregister(hook_node, 0);
pr_err("error in extension, unloading: %s",
hook_node->name);
+ __battery_hook_unregister(hook_node, 0);
}
}
mutex_unlock(&hook_mutex);
--
2.18.0