[PATCH] warn about shared irqs requesting IRQF_DISABLED registered with setup_irq

From: Uwe Kleine-KÃnig
Date: Fri Nov 27 2009 - 16:10:22 EST


IRQF_DISABLED is not guaranteed on shared irqs. There is already a
warning in place for irqs registered with request_irq (introduced in
470c66239ef03). Move it to __setup_irq, this way it triggers for both
request_irq and setup_irq.

One irq that is now warned about is the timer tick on at91 (ARCH=arm).

Signed-off-by: Uwe Kleine-KÃnig <u.kleine-koenig@xxxxxxxxxxxxxx>
Cc: David Brownell <dbrownell@xxxxxxxxxxxxxxxxxxxxx>
Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Nicolas Pitre <nico@xxxxxxxxxxx>
Cc: Eric Miao <eric.y.miao@xxxxxxxxx>
Cc: John Stultz <johnstul@xxxxxxxxxx>
Cc: Rusty Russell <rusty@xxxxxxxxxxxxxxx>
Cc: Remy Bohmer <linux@xxxxxxxxxx>,
Cc: Hugh Dickins <hugh.dickins@xxxxxxxxxxxxx>,
Cc: Andrea Gallo <andrea.gallo@xxxxxxxxxxxxxx>,
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>,
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
---
kernel/irq/manage.c | 26 +++++++++++++-------------
1 files changed, 13 insertions(+), 13 deletions(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index bde4c66..59f4b54 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -613,6 +613,19 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
int nested, shared = 0;
int ret;

+ /*
+ * handle_IRQ_event() always ignores IRQF_DISABLED except for
+ * the _first_ irqaction (sigh). That can cause oopsing, but
+ * the behavior is classified as "will not fix" so we need to
+ * start nudging drivers away from using that idiom.
+ */
+ if ((new->flags & (IRQF_SHARED|IRQF_DISABLED)) ==
+ (IRQF_SHARED|IRQF_DISABLED)) {
+ pr_warning(
+ "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
+ irq, new->name);
+ }
+
if (!desc)
return -EINVAL;

@@ -1008,19 +1021,6 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
struct irq_desc *desc;
int retval;

- /*
- * handle_IRQ_event() always ignores IRQF_DISABLED except for
- * the _first_ irqaction (sigh). That can cause oopsing, but
- * the behavior is classified as "will not fix" so we need to
- * start nudging drivers away from using that idiom.
- */
- if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
- (IRQF_SHARED|IRQF_DISABLED)) {
- pr_warning(
- "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
- irq, devname);
- }
-
#ifdef CONFIG_LOCKDEP
/*
* Lockdep wants atomic interrupt handlers:
--
1.6.5.2

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