--- linux/arch/i386/kernel/irq.c.org	Thu Feb 28 14:05:56 2002
+++ linux/arch/i386/kernel/irq.c	Fri Mar  1 12:40:37 2002
@@ -577,7 +577,17 @@
 	irq_desc_t *desc = irq_desc + irq;
 	struct irqaction * action;
 	unsigned int status;
+	long esp;
 
+	/* Debugging check for stack overflow: is there less than 2KB free? */
+	__asm__ __volatile__("andl %%esp,%0" : "=r" (esp) : "0" (8191));
+	if (esp < (sizeof(struct task_struct) + 2048)) {
+		printk("do_IRQ: stack overflow: %ld\n",
+			esp - sizeof(struct task_struct));
+		__asm__ __volatile__("movl %%esp,%0" : "=r" (esp));
+		show_stack((void *)esp);
+	}
+	
 	kstat.irqs[cpu][irq]++;
 	spin_lock(&desc->lock);
 	desc->handler->ack(irq);