Re: [PATCH] Fix shared interrupt handling of SA_INTERRUPT and SA_SAMPLE_RANDOM

[Russell King <rmk+lkml@arm.linux.org.uk>]

On Thu, Aug 26, 2004 at 02:50:52PM +0200, Takashi Iwai wrote:
> At Wed, 25 Aug 2004 13:41:12 -0700,
> Andrew Morton wrote:
> > 
> > Takashi Iwai <tiwai@suse.de> wrote:
> > >
> > > Anyway, suppressing the unnecessary call of add_interrupt_randomness()
> > >  should be still valid.  The reduced patch is below.
> (snip)
> > 
> > Shouldn't that be `if (ret == IRQ_HANDLED)'?
> 
> Yes, it's more strict.

I don't think so.  Look at what's going on.  If "ret" is IRQ_HANDLED
all well and fine.  However, look at how "retval" is being used:

static void __report_bad_irq(int irq, irq_desc_t *desc, irqreturn_t action_ret)
{
...
        if (action_ret != IRQ_HANDLED && action_ret != IRQ_NONE) {
                printk(KERN_ERR "irq event %d: bogus return value %x\n",
                                irq, action_ret);
        } else {
                printk(KERN_ERR "irq %d: nobody cared!\n", irq);
        }

So, we're looking to see not only if a handler returned IRQ_HANDLED,
but also if a handler returned _some other value_ other than IRQ_HANDLED
or IRQ_NONE.

-- 
Russell King
 Linux kernel    2.6 ARM Linux   - http://www.arm.linux.org.uk/
 maintainer of:  2.6 PCMCIA      - http://pcmcia.arm.linux.org.uk/
                 2.6 Serial core