on preemption being disabled to be functional. So that code
path was either never tested or never tested with CONFIG_DEBUG_PREEMPT
enabled.

Add the missing preempt_disable/enable() pair around the call.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Chen Gong <gong.chen@linux.intel.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>