Patch "bus: arm-ccn: Fix irq affinity setting on CPU migration" has been added to the 4.2-stable tree

Patch "bus: arm-ccn: Fix irq affinity setting on CPU migration" has been added to the 4.2-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    bus: arm-ccn: Fix irq affinity setting on CPU migration

to the 4.2-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     bus-arm-ccn-fix-irq-affinity-setting-on-cpu-migration.patch
and it can be found in the queue-4.2 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From a0bcbe969f564d1ec08658170dda72a1b7e9053a Mon Sep 17 00:00:00 2001
From: Pawel Moll <pawel.moll@arm.com>
Date: Thu, 15 Oct 2015 14:32:46 +0100
Subject: bus: arm-ccn: Fix irq affinity setting on CPU migration

From: Pawel Moll <pawel.moll@arm.com>

commit a0bcbe969f564d1ec08658170dda72a1b7e9053a upstream.

When PMU context is migrating between CPUs, interrupt affinity is set as
well. Only this should not happen when the CCN interrupt is not being
used at all (the driver is using a hrtimer tick instead).

Fixed now.

Signed-off-by: Pawel Moll <pawel.moll@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 drivers/bus/arm-ccn.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/drivers/bus/arm-ccn.c
+++ b/drivers/bus/arm-ccn.c
@@ -1188,7 +1188,8 @@ static int arm_ccn_pmu_cpu_notifier(stru
 			break;
 		perf_pmu_migrate_context(&dt->pmu, cpu, target);
 		cpumask_set_cpu(target, &dt->cpu);
-		WARN_ON(irq_set_affinity(ccn->irq, &dt->cpu) != 0);
+		if (ccn->irq)
+			WARN_ON(irq_set_affinity(ccn->irq, &dt->cpu) != 0);
 	default:
 		break;
 	}


Patches currently in stable-queue which might be from pawel.moll@arm.com are

queue-4.2/bus-arm-ccn-fix-irq-affinity-setting-on-cpu-migration.patch