Re: [PATCH 01/28] genirq: Add missing "else" in irq_shutdown()

Thomas Gleixner
2011-09-12T07:53:56Z

On Sun, 11 Sep 2011, Geert Uytterhoeven wrote:

> If an irq_chip provides .irq_shutdown(), but neither of .irq_disable() or
> .irq_mask(), free_irq() crashes when jumping to NULL.
> Fix this by only trying .irq_disable() and .irq_mask() if there's no
> .irq_shutdown() provided.
>
> This revives the symmetry with irq_startup(), which tries .irq_startup(),
> .irq_enable(), and irq_unmask(), and makes it consistent with the comment for
> irq_chip.irq_shutdown() in <linux/irq.h>, which says:
>
> * @irq_shutdown: shut down the interrupt (defaults to ->disable if NULL)
>
> This is also how __free_irq() behaved before the big overhaul, cfr. e.g.
> 3b56f0585fd4c02d047dc406668cb40159b2d340 ("genirq: Remove bogus conditional"),
> where the core interrupt code always overrode .irq_shutdown() to
> .irq_disable() if .irq_shutdown() was NULL.
>
> Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
> Cc: Thomas Gleixner <tglx@linutronix.de>

Applied into irq/urgent with a note to stable@...

Thanks,

tglx