leandrof/linux
1
0
Fork 0
forked from Minki/linux
Code Issues Pull Requests Packages Projects Releases Wiki Activity

generic irqs: handle failure of irqchip->set_type in setup_irq

Browse Source 
set_type returns an int indicating success or failure, but up to now
setup_irq ignores that.

In my case this resulted in a machine hang:

gpio-keys requested IRQF_TRIGGER_RISING | IRQF_TRIGGER_FALLING, but
arm/ns9xxx can only trigger on one direction so set_type didn't touch
the configuration which happens do default to a level sensitiveness and
returned -EINVAL.  setup_irq ignored that and unmasked the irq.  This
resulted in an endless triggering of the gpio-key interrupt service
routine which effectively killed the machine.

With this patch applied setup_irq propagates the error to the caller.

Note that before in the case

	chip && !chip->set_type && !chip->name

a NULL pointer was feed to printk.  This is fixed, too.

Signed-off-by: Uwe Kleine-König <Uwe.Kleine-Koenig@digi.com>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This commit is contained in:
Uwe Kleine-König 2008-07-23 21:28:54 -07:00 committed by Linus Torvalds
parent f606ddf42f
commit 82736f4d1d
1 changed files with 42 additions and 22 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

64
kernel/irq/manage.c
View File

@ -308,6 +308,30 @@ void compat_irq_chip_set_default_handler(struct irq_desc *desc)
desc->handle_irq = NULL;
}
static int __irq_set_trigger(struct irq_chip *chip, unsigned int irq,
unsigned long flags)
{
int ret;
if (!chip || !chip->set_type) {
/*
* IRQF_TRIGGER_* but the PIC does not support multiple
* flow-types?
*/
pr_warning("No set_type function for IRQ %d (%s)\n", irq,
chip ? (chip->name ? : "unknown") : "unknown");
return 0;
}
ret = chip->set_type(irq, flags & IRQF_TRIGGER_MASK);
if (ret)
pr_err("setting flow type for irq %u failed (%pF)\n",
irq, chip->set_type);
return ret;
}
/*
* Internal function to register an irqaction - typically used to
* allocate special interrupts that are part of the architecture.
@ -319,6 +343,7 @@ int setup_irq(unsigned int irq, struct irqaction *new)
const char *old_name = NULL;
unsigned long flags;
int shared = 0;
int ret;
if (irq >= NR_IRQS)
return -EINVAL;
@ -376,36 +401,24 @@ int setup_irq(unsigned int irq, struct irqaction *new)
shared = 1;
}
*p = new;
/* Exclude IRQ from balancing */
if (new->flags & IRQF_NOBALANCING)
desc->status |= IRQ_NO_BALANCING;
if (!shared) {
irq_chip_set_defaults(desc->chip);
/* Setup the type (level, edge polarity) if configured: */
if (new->flags & IRQF_TRIGGER_MASK) {
ret = __irq_set_trigger(desc->chip, irq, new->flags);
if (ret) {
spin_unlock_irqrestore(&desc->lock, flags);
return ret;
}
} else
compat_irq_chip_set_default_handler(desc);
#if defined(CONFIG_IRQ_PER_CPU)
if (new->flags & IRQF_PERCPU)
desc->status |= IRQ_PER_CPU;
#endif
/* Setup the type (level, edge polarity) if configured: */
if (new->flags & IRQF_TRIGGER_MASK) {
if (desc->chip->set_type)
desc->chip->set_type(irq,
new->flags & IRQF_TRIGGER_MASK);
else
/*
* IRQF_TRIGGER_* but the PIC does not support
* multiple flow-types?
*/
printk(KERN_WARNING "No IRQF_TRIGGER set_type "
"function for IRQ %d (%s)\n", irq,
desc->chip->name);
} else
compat_irq_chip_set_default_handler(desc);
desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING |
IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED);
@ -423,6 +436,13 @@ int setup_irq(unsigned int irq, struct irqaction *new)
/* Set default affinity mask once everything is setup */
irq_select_affinity(irq);
}
*p = new;
/* Exclude IRQ from balancing */
if (new->flags & IRQF_NOBALANCING)
desc->status |= IRQ_NO_BALANCING;
/* Reset broken irq detection when installing new handler */
desc->irq_count = 0;
desc->irqs_unhandled = 0;