The user space interface does not filter out offline cpus. It merily verifies that the mask contains at least one online cpu. So the selector in the irq chip implementation needs to make sure to pick only an online cpu because otherwise: Offline Core 1 Set affinity to 0xe Selector will pick first set bit, i.e. core 1 Signed-off-by: Thomas Gleixner Cc: David Vrabel Cc: Peter Zijlstra Cc: Konrad Rzeszutek Wilk Cc: Xen --- drivers/xen/events/events_base.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: tip/drivers/xen/events/events_base.c =================================================================== --- tip.orig/drivers/xen/events/events_base.c +++ tip/drivers/xen/events/events_base.c @@ -1324,7 +1324,7 @@ static int rebind_irq_to_cpu(unsigned ir static int set_affinity_irq(struct irq_data *data, const struct cpumask *dest, bool force) { - unsigned tcpu = cpumask_first(dest); + unsigned tcpu = cpumask_first_and(dest, cpu_online_mask); return rebind_irq_to_cpu(data->irq, tcpu); } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/