On Wed, Jun 25, 2014 at 04:40:31PM +0800, Jiang Liu wrote:
> This patch set enhances IOAPIC core and ACPI drivers to support IOAPIC
> hotplug on x86 platforms. It's based on tip/x86/apic.
> 
> You may pull it from 
> https://github.com/jiangliu/linux.git ioapic/hotplug_v3

With this patchset (on top of 3.16-rc5) my USB driver gets notified
it has interrupts but it thinks it does not have to acknowledge any.
I can only reproduce this under a 32-bit arch so far.

Please see the good.log and the bad.log