The [user space] interface does not filter out offline cpus. It merily guarantees 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 (is valid due to online mask 0xd) cpumask_first will pick core 1, which is offline Signed-off-by: Thomas Gleixner Cc: "James E.J. Bottomley" Cc: Helge Deller Cc: linux-parisc@vger.kernel.org --- arch/parisc/kernel/irq.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) Index: tip/arch/parisc/kernel/irq.c =================================================================== --- tip.orig/arch/parisc/kernel/irq.c +++ tip/arch/parisc/kernel/irq.c @@ -117,7 +117,7 @@ int cpu_check_affinity(struct irq_data * return -EINVAL; /* whatever mask they set, we just allow one CPU */ - cpu_dest = first_cpu(*dest); + cpu_dest = cpumask_first_and(dest, cpu_online_mask); return cpu_dest; } -- 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/