Re: [PATCH 07/11] mfd: menelaus: use devm_request_irq() anddevm_kzalloc()

From: Dmitry Torokhov
Date: Wed Feb 20 2013 - 02:30:52 EST


Hi Jongoo,

On Wed, Feb 20, 2013 at 03:12:38PM +0900, Jingoo Han wrote:
> Use devm_request_irq() and devm_kzalloc() to make cleanup paths
> more simple.
>

...

> @@ -1269,9 +1266,7 @@ static int __exit menelaus_remove(struct i2c_client *client)
> {
> struct menelaus_chip *menelaus = i2c_get_clientdata(client);
>
> - free_irq(client->irq, menelaus);
> flush_work(&menelaus->work);
> - kfree(menelaus);
> the_menelaus = NULL;
> return 0;

This conversion is certainly wrong - you really want to disable IRQ and
then wait for the scheduled work to finish before freeing memory. Here
you flush work but nothing stops IRQ from firing and scheduling that
work again.

Please, be *extra* careful with devm_request_irq() conversions.

Thanks.

--
Dmitry
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