[PATCH 4.4 329/342] x86/irq: Copy vectormask instead of an AND operation

[Greg Kroah-Hartman]

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

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

From: Thomas Gleixner <tglx@xxxxxxxxxxxxx>

commit 9ac15b7a8af4cf3337a101498c0ed690d23ade75 upstream.

In the case that the new vector mask is a subset of the existing mask there is
no point to do a AND operation of currentmask & newmask. The result is
newmask. So we can simply copy the new mask to the current mask and be done
with it. Preparatory patch for further consolidation.

Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Tested-by: Borislav Petkov <bp@xxxxxxxxx>
Tested-by: Joe Lawrence <joe.lawrence@xxxxxxxxxxx>
Cc: Jiang Liu <jiang.liu@xxxxxxxxxxxxxxx>
Cc: Jeremiah Mahler <jmmahler@xxxxxxxxx>
Cc: andy.shevchenko@xxxxxxxxx
Cc: Guenter Roeck <linux@xxxxxxxxxxxx>
Link: http://lkml.kernel.org/r/20151231160106.640253454@xxxxxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 arch/x86/kernel/apic/vector.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/arch/x86/kernel/apic/vector.c
+++ b/arch/x86/kernel/apic/vector.c
@@ -154,7 +154,7 @@ static int __assign_irq_vector(int irq,
 				       vector_cpumask);
 			d->move_in_progress =
 			   cpumask_intersects(d->old_domain, cpu_online_mask);
-			cpumask_and(d->domain, d->domain, vector_cpumask);
+			cpumask_copy(d->domain, vector_cpumask);
 			goto success;
 		}