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

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

[Marc Zyngier]

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@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
---
 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 63c1625..6e04134 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

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

[Thomas Gleixner]

On Wed, 16 Nov 2011, Marc Zyngier wrote:

Queued for 3.2. Thanks for the reminder!

       tglx

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

[tip-bot for Marc Zyngier]

Commit-ID:  2ed0e645f358c26f4f4a7aed56a9488db0020ad1
Gitweb:     http://git.kernel.org/tip/2ed0e645f358c26f4f4a7aed56a9488db0020ad1
Author:     Marc Zyngier <marc.zyngier@arm.com>
AuthorDate: Wed, 16 Nov 2011 12:27:39 +0000
Committer:  Thomas Gleixner <tglx@linutronix.de>
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@ti.com>
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1321446459-31409-1-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
 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;