void ist_begin_non_atomic(struct pt_regs *regs)
{
	BUG_ON(!user_mode(regs));

	/*
	 * Sanity check: we need to be on the normal thread stack.  This
	 * will catch asm bugs and any attempt to use ist_preempt_enable
	 * from double_fault.
	 */
	BUG_ON(!on_thread_stack());

	preempt_enable_no_resched();
}
void ist_begin_non_atomic(struct pt_regs *regs)
{
	BUG_ON(!user_mode(regs));

	 
	BUG_ON(!on_thread_stack());

	preempt_enable_no_resched();
}