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Subject[PATCH] free_irq(): Actually handle DEBUG_SHIRQ
 Code used for DEBUG_SHIRQ in free_irq() is unreachable -- the for() loop 
within never terminates otherwise than by return. This is an obvious fix.

Signed-off-by: Maciej W. Rozycki <macro@linux-mips.org>
---
Please apply.

While at it, I have a question about the complementary code within
request_irq(): when the option in question is enabled, a spurious IRQ is
posted before internal setup is done by setup_irq(). This includes the
->depth counter. Now if the interrupt handler of some driver calls
disable_irq_nosync(), then code in setup_irq() will mess up the state of
->depth afterwards if this is the first handler being installed (i.e.
within the "if (!shared)" block). This is reported later on when
enable_irq() called by the driver, by means of a message like this:

Unbalanced enable for IRQ 34
WARNING: at kernel/irq/manage.c:158 enable_irq()

Now given DEBUG_SHIRQ is a debug facility, not to be normally used for
production, is the phenomenon as described considered a design limitation
we can live with, or is it a bug that qualifies for a fix?

I can reproduce this problem easily with phylib.

Maciej

patch-mips-2.6.23-rc5-20070904-debug-shirq-0
diff -up --recursive --new-file linux-mips-2.6.23-rc5-20070904.macro/kernel/irq/manage.c linux-mips-2.6.23-rc5-20070904/kernel/irq/manage.c
--- linux-mips-2.6.23-rc5-20070904.macro/kernel/irq/manage.c 2007-09-04 04:56:21.000000000 +0000
+++ linux-mips-2.6.23-rc5-20070904/kernel/irq/manage.c 2007-09-11 23:58:59.000000000 +0000
@@ -448,7 +448,7 @@ void free_irq(unsigned int irq, void *de
if (action->flags & IRQF_SHARED)
handler = action->handler;
kfree(action);
- return;
+ break;
}
printk(KERN_ERR "Trying to free already-free IRQ %d\n", irq);
spin_unlock_irqrestore(&desc->lock, flags);
-
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