diff -uNrp linux-2.6.31.1-xeno-perso/arch/x86/kernel/apic/io_apic.c linux-2.6.31.1-xeno-perso-x86_64-local/arch/x86/kernel/apic/io_apic.c
--- linux-2.6.31.1-xeno-perso/arch/x86/kernel/apic/io_apic.c	2009-10-16 15:39:55.000000000 +0200
+++ linux-2.6.31.1-xeno-perso-x86_64-local/arch/x86/kernel/apic/io_apic.c	2009-11-29 23:34:40.000000000 +0100
@@ -1357,6 +1357,11 @@ static inline int IO_APIC_irq_trigger(in
 static void ioapic_register_intr(int irq, struct irq_desc *desc, unsigned long trigger)
 {
 
+#if 1 /* debug */
+	printk("ioapic_register_intr: irq = %d, trig = %lu, apic_trig = %d, remap = %d\n",
+	       irq, trigger, IO_APIC_irq_trigger(irq), irq_remapped(irq));
+#endif /* debug */
+
 	if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
 	    trigger == IOAPIC_LEVEL)
 		desc->status |= IRQ_LEVEL;