Re: [PATCH v2] irq: generic-chip: provide irq_free_generic_chip()

From: Bartosz Golaszewski
Date: Thu Mar 09 2017 - 05:44:45 EST


2017-03-09 11:17 GMT+01:00 Thomas Gleixner <tglx@xxxxxxxxxxxxx>:
> On Wed, 8 Mar 2017, Bartosz Golaszewski wrote:
>
>> Some users of irq_alloc_generic_chip() are modules which can be
>> removed (e.g. gpio-ml-ioh) but have no means of freeing the allocated
>> generic chip. Provide a function for that.
>
> They have means, i.e. kfree(gc). If you want a wrapper for that then please
> make it a simple static inline w/o the bloat of an exported symbol.
>

Yes, I want a wrapper, since there are no guarantees as to what
irq_alloc_generic_chip() does internally.

> But, what you really want is a proper counterpart to
> irq_alloc_generic_chip() which undoes everything what
> irq_alloc_generic_chip() does.
>
> You have to call irq_remove_generic_chip() before calling kfree() or the
> wrapper anyway. And looking at the 3 users of irq_remove_generic_chip():
>
> Two of them (drivers/gpio/gpio-tb10x.c drivers/mfd/jz4740-adc.c) do
>
> irq_remove_generic_chip(gc)
> kfree(gc)
>
> The third one (arch/arm/mach-omap2/prm_common.c) leaks the generic chip
> memory....
>
> So the proper solution is to rename irq_remove_generic_chip() to
> irq_destroy_generic_chip() and do the kfree() at the end of that function.
>
> Hmm?
>

Sounds good!

Thanks,
Bartosz