[tip:irq/urgent] genirq: Don't allow per cpu interrupts to be suspended

From: tip-bot for Marc Zyngier
Date: Fri Nov 18 2011 - 18:48:46 EST


Commit-ID: 2ed0e645f358c26f4f4a7aed56a9488db0020ad1
Gitweb: http://git.kernel.org/tip/2ed0e645f358c26f4f4a7aed56a9488db0020ad1
Author: Marc Zyngier <marc.zyngier@xxxxxxx>
AuthorDate: Wed, 16 Nov 2011 12:27:39 +0000
Committer: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
CommitDate: Thu, 17 Nov 2011 17:44:04 +0100

genirq: Don't allow per cpu interrupts to be suspended

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>
Tested-by: Santosh Shilimkar <santosh.shilimkar@xxxxxx>
Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/1321446459-31409-1-git-send-email-marc.zyngier@xxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
---
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;

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/