[75/88] genirq: Fix can_request_irq() for IRQs without an action

Steven Rostedt
2013-08-13T16:34:49Z

[-- Attachment #1: 0075-genirq-Fix-can_request_irq-for-IRQs-without-an-actio.patch --]
[-- Type: text/plain, Size: 1684 bytes --]

3.6.11.7-rc1 stable review patch.
If anyone has any objections, please let me know.

------------------

From: Ben Hutchings <ben@decadent.org.uk>

[ Upstream commit 2779db8d37d4b542d9ca2575f5f178dbeaca6c86 ]

Commit 02725e7471b8 ('genirq: Use irq_get/put functions'),
inadvertently changed can_request_irq() to return 0 for IRQs that have
no action. This causes pcibios_lookup_irq() to select only IRQs that
already have an action with IRQF_SHARED set, or to fail if there are
none. Change can_request_irq() to return 1 for IRQs that have no
action (if the first two conditions are met).

Reported-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is>
Tested-by: Bjarni Ingi Gislason <bjarniig@rhi.hi.is> (against 3.2)
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: 709647@bugs.debian.org
Cc: stable@vger.kernel.org # 2.6.39+
Link: http://bugs.debian.org/709647
Link: http://lkml.kernel.org/r/1372383630.23847.40.camel@deadeye.wl.decadent.org.uk
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/irq/manage.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 4c69326..50a0a66 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -554,9 +554,9 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
return 0;

if (irq_settings_can_request(desc)) {
- if (desc->action)
- if (irqflags & desc->action->flags & IRQF_SHARED)
- canrequest =1;
+ if (!desc->action ||
+ irqflags & desc->action->flags & IRQF_SHARED)
+ canrequest = 1;
}
irq_put_desc_unlock(desc, flags);
return canrequest;
--
1.7.10.4