On Wed, 2007-02-21 at 20:23 +0100, Thomas Gleixner wrote: > On Wed, 2007-02-21 at 10:23 -0800, Daniel Walker wrote: > > Right, but eventually there isn't a regular timer interrupt through the > > io-apic. I don't think in the past IRQ0 stops without the system > > crashing, so check_timer() could assume the timer (IRQ0) is _always_ > > regular. > > > > do you know what the requirement are for routing the NMI through the > > io-apic? > > Sorry. I checked. switching PIT off really breaks nmi_watchdog=1, as > this just mirrors IRQ#0 to the NMI. No IRQ#0 from PIT, no NMI
That's what I suspected .. > We could keep PIT running with an empty interrupt handler when > nmi_watchdog=1 is set, but this interferes nicely with broadcasting. > > Does nmi_watchdog=2 work ? We might switch to that, when a local APIC is > available. Oddly, nmi_watchdog=2 doesn't work in 2.6.21-rc1, but it works in 2.6.20-rt8 however I'm not sure of the config could have been PREEMPT_RT was on. Daniel - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/