Hi,
On 2-Oct-24 2:08 PM, Rafael J. Wysocki wrote:
> On Tue, Oct 1, 2024 at 11:28 PM Armin Wolf <W_Armin@xxxxxx> wrote:
>>
>> When a battery hook returns an error when adding a new battery, then
>> the battery hook is automatically unregistered.
>> However the battery hook provider cannot know that, so it will later
>> call battery_hook_unregister() on the already unregistered battery
>> hook, resulting in a crash.
>>
>> Fix this by using the list head to mark already unregistered battery
>> hooks as already being unregistered so that they can be ignored by
>> battery_hook_unregister().
>>
>> Fixes: fa93854f7a7e ("battery: Add the battery hooking API")
>> Signed-off-by: Armin Wolf <W_Armin@xxxxxx>
>
> Acked-by: Rafael J. Wysocki <rafael.j.wysocki@xxxxxxxxx>
>
> Hans, are you going to take this series or should I apply it?
AFAICT the patches don't really depend on each other, so my plan
was that you take patches 1-2 and I take patch 3 as a fix for
6.12-rc# .
Does that work for you ?
Regards,
Hans
>
>> ---
>> drivers/acpi/battery.c | 12 +++++++++---
>> 1 file changed, 9 insertions(+), 3 deletions(-)
>>
>> diff --git a/drivers/acpi/battery.c b/drivers/acpi/battery.c
>> index dda59ee5a11e..1c45ff6dbb83 100644
>> --- a/drivers/acpi/battery.c
>> +++ b/drivers/acpi/battery.c
>> @@ -715,7 +715,7 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
>> if (!hook->remove_battery(battery->bat, hook))
>> power_supply_changed(battery->bat);
>> }
>> - list_del(&hook->list);
>> + list_del_init(&hook->list);
>>
>> pr_info("extension unregistered: %s\n", hook->name);
>> }
>> @@ -723,7 +723,14 @@ static void battery_hook_unregister_unlocked(struct acpi_battery_hook *hook)
>> void battery_hook_unregister(struct acpi_battery_hook *hook)
>> {
>> mutex_lock(&hook_mutex);
>> - battery_hook_unregister_unlocked(hook);
>> + /*
>> + * Ignore already unregistered battery hooks. This might happen
>> + * if a battery hook was previously unloaded due to an error when
>> + * adding a new battery.
>> + */
>> + if (!list_empty(&hook->list))
>> + battery_hook_unregister_unlocked(hook);
>> +
>> mutex_unlock(&hook_mutex);
>> }
>> EXPORT_SYMBOL_GPL(battery_hook_unregister);
>> @@ -733,7 +740,6 @@ void battery_hook_register(struct acpi_battery_hook *hook)
>> struct acpi_battery *battery;
>>
>> mutex_lock(&hook_mutex);
>> - INIT_LIST_HEAD(&hook->list);
>> list_add(&hook->list, &battery_hook_list);
>> /*
>> * Now that the driver is registered, we need
>> --
>> 2.39.5
>>
>
