* Maciej W. Rozycki <macro@xxxxxxxxxxxxxx> wrote: > --- a/arch/x86/kernel/io_apic_64.c 2008-06-18 22:53:34.000000000 +0000 > +++ b/arch/x86/kernel/io_apic_64.c 2008-06-18 22:58:45.000000000 +0000 > @@ -1714,6 +1714,7 @@ static inline void __init check_timer(vo > /* replace_pin_at_irq(0, apic1, pin1, apic2, pin2); */ > setup_timer_IRQ0_pin(apic2, pin2, cfg->vector); > unmask_IO_APIC_irq(0); > + clear_IO_APIC_pin(apic2, pin2); > enable_8259A_irq(0); > if (timer_irq_works()) { > apic_printk(APIC_VERBOSE," works.\n"); would it be fine with you if we applied this to tip/x86, as it unbreaks Rafael's box? does PIT programming matter? One detail which might matter and which touches IRQ0 generation is the clockevent driver on nohz/highres. See arch/x86/kernel/i8253.c:init_pit_timer(): case CLOCK_EVT_MODE_SHUTDOWN: case CLOCK_EVT_MODE_UNUSED: if (evt->mode == CLOCK_EVT_MODE_PERIODIC || evt->mode == CLOCK_EVT_MODE_ONESHOT) { outb_pit(0x30, PIT_MODE); outb_pit(0, PIT_CH0); outb_pit(0, PIT_CH0); } pit_disable_clocksource(); break; case CLOCK_EVT_MODE_ONESHOT: /* One shot setup */ pit_disable_clocksource(); outb_pit(0x38, PIT_MODE); break; Ingo -- To unsubscribe from this list: send the line "unsubscribe linux-acpi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html