[PATCH] setup_irq(): better mismatch debugging
When we get a mismatch between handlers on the same IRQ, all we get is "IRQ
handler type mismatch for IRQ n". Let's print the name of the
presently-registered handler with which we got the mismatch.
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 6879202..b385878 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -216,6 +216,7 @@
{
struct irq_desc *desc = irq_desc + irq;
struct irqaction *old, **p;
+ const char *old_name = NULL;
unsigned long flags;
int shared = 0;
@@ -255,8 +256,10 @@
* set the trigger type must match.
*/
if (!((old->flags & new->flags) & IRQF_SHARED) ||
- ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK))
+ ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) {
+ old_name = old->name;
goto mismatch;
+ }
#if defined(CONFIG_IRQ_PER_CPU)
/* All handlers must agree on per-cpuness */
@@ -322,11 +325,13 @@
return 0;
mismatch:
- spin_unlock_irqrestore(&desc->lock, flags);
if (!(new->flags & IRQF_PROBE_SHARED)) {
printk(KERN_ERR "IRQ handler type mismatch for IRQ %d\n", irq);
+ if (old_name)
+ printk(KERN_ERR "current handler: %s\n", old_name);
dump_stack();
}
+ spin_unlock_irqrestore(&desc->lock, flags);
return -EBUSY;
}