[PATCH] genirq: don't allow per cpu interrupts to be suspended

From: Marc Zyngier
Date: Tue Nov 08 2011 - 09:48:39 EST


The power management functions related to interrupts do not know
(yet) about per-cpu interrupts and end up calling the wrong
low-level methods to enable/disable interrupts.

This leads to all kind of interesting issues (action taken on one
CPU only, updating a refcount which is not used otherwise...).

The workaround for the time being is simply to flag these interrupts
with IRQF_NO_SUSPEND. At least on ARM, these interrupts are actually
dealt with at the architecture level.

Reported-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
kernel/irq/manage.c | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 67ce837..0e2b179 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -1596,7 +1596,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler,
return -ENOMEM;

action->handler = handler;
- action->flags = IRQF_PERCPU;
+ action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND;
action->name = devname;
action->percpu_dev_id = dev_id;

--
1.7.0.4


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