From 002fca5df168922103a2bb52748f9984e6de80b2 Mon Sep 17 00:00:00 2001 From: Axel Lin Date: Fri, 5 Jul 2013 17:13:12 +0800 Subject: genirq: generic chip: Use DIV_ROUND_UP to calculate numchips The number of interrupts in a domain may be not divisible by the number of interrupts each chip handles. Integer division may truncate the result, thus use DIV_ROUND_UP to count numchips. Seems all users of irq_alloc_domain_generic_chips() in current code do not have this issue. I just found the issue while reading the code. Signed-off-by: Axel Lin Cc: Grant Likely Cc: Tony Lindgren Cc: Arnd Bergmann Link: http://lkml.kernel.org/r/1373015592.18252.2.camel@phoenix Signed-off-by: Thomas Gleixner --- kernel/irq/generic-chip.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'kernel/irq') diff --git a/kernel/irq/generic-chip.c b/kernel/irq/generic-chip.c index 1c39eccc1ea..2f274f30b7e 100644 --- a/kernel/irq/generic-chip.c +++ b/kernel/irq/generic-chip.c @@ -278,7 +278,7 @@ int irq_alloc_domain_generic_chips(struct irq_domain *d, int irqs_per_chip, if (d->revmap_type != IRQ_DOMAIN_MAP_LINEAR) return -EINVAL; - numchips = d->revmap_data.linear.size / irqs_per_chip; + numchips = DIV_ROUND_UP(d->revmap_data.linear.size, irqs_per_chip); if (!numchips) return -EINVAL; -- cgit v1.2.3-70-g09d2