We pre-reserve irq range for hot-added ioapic, and later only some are used via realloc. So during hot-remove, we need to clear bits in allocated_irqs for both case. Check if the irq_desc is there at first, and bail out early if irq_desc is not allocated yet. So we can use irq_free_descs to clear allocated_irqs bits for preserved irqs. Signed-off-by: Yinghai Lu <yinghai@xxxxxxxxxx> --- kernel/irq/irqdesc.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/kernel/irq/irqdesc.c b/kernel/irq/irqdesc.c index b48f65b..32f099e 100644 --- a/kernel/irq/irqdesc.c +++ b/kernel/irq/irqdesc.c @@ -170,6 +170,9 @@ static void free_desc(unsigned int irq) { struct irq_desc *desc = irq_to_desc(irq); + if (!desc) + return; + unregister_irq_proc(irq, desc); mutex_lock(&sparse_irq_lock); -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html