genirq: fix regression in irqfixup, irqpoll
Edward Donovan [Mon, 28 Nov 2011 04:07:34 +0000 (23:07 -0500)]
commit 52553ddffad76ccf192d4dd9ce88d5818f57f62a upstream.

Commit fa27271bc8d2("genirq: Fixup poll handling") introduced a
regression that broke irqfixup/irqpoll for some hardware configurations.

Amidst reorganizing 'try_one_irq', that patch removed a test that
checked for 'action->handler' returning IRQ_HANDLED, before acting on
the interrupt.  Restoring this test back returns the functionality lost
since 2.6.39.  In the current set of tests, after 'action' is set, it
must precede '!action->next' to take effect.

With this and my previous patch to irq/spurious.c, c75d720fca8a, all
IRQ regressions that I have encountered are fixed.

Signed-off-by: Edward Donovan <edward.donovan@numble.net>
Reported-and-tested-by: RogĂ©rio Brito <rbrito@ime.usp.br>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

kernel/irq/spurious.c

index b5f4742..dc813a9 100644 (file)
@@ -84,7 +84,9 @@ static int try_one_irq(int irq, struct irq_desc *desc, bool force)
         */
        action = desc->action;
        if (!action || !(action->flags & IRQF_SHARED) ||
-           (action->flags & __IRQF_TIMER) || !action->next)
+           (action->flags & __IRQF_TIMER) ||
+           (action->handler(irq, action->dev_id) == IRQ_HANDLED) ||
+           !action->next)
                goto out;
 
        /* Already running on another processor */