The hang was caused by the use of disable_irq() from the interrupt handler
itself. Fixed by the use of disable_irq_nosync(). The issue was
triggered by:
commit 3aa551c9b4c40018f0e261a178e3d25478dc04a9
Author: Thomas Gleixner <tglx@linutronix.de>
Date: Mon Mar 23 18:28:15 2009 +0100
genirq: add threaded interrupt handler support
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>