Re: [PATCH v2 4/4] platform/x86: ideapad-laptop: add a mutex to synchronize VPC commands

From: Hans de Goede
Date: Thu Jul 18 2024 - 04:12:28 EST


Hi,

On 7/18/24 10:06 AM, Ilpo Järvinen wrote:
> On Thu, 18 Jul 2024, Gergo Koteles wrote:
>
>> Calling VPC commands consists of several VPCW and VPCR ACPI calls.
>> These calls and their results can get mixed up if they are called
>> simultaneously from different threads, like acpi notify handler,
>> sysfs, debugfs, notification chain.
>>
>> Add a mutex to synchronize VPC commands.
>>
>> Signed-off-by: Gergo Koteles <soyer@xxxxxx>
>> ---
>
>> @@ -2027,6 +2053,8 @@ static int ideapad_acpi_add(struct platform_device *pdev)
>> priv->adev = adev;
>> priv->platform_device = pdev;
>>
>> + mutex_init(&priv->vpc_mutex);
>> +
>> ideapad_check_features(priv);
>>
>> err = ideapad_sysfs_init(priv);
>
> mutex_destroy() missing from rollback and ideapad_acpi_remove().

Right, note the easiest way to fix this is to use the new devm_mutex_init()
instead of plain mutex_init() that will also take care of destroying the mutex
on any exit-on-error cases from probe().

Regards,

Hans