Re: Latest tip kernel(3.2-rc1-tip_cf6b3899) fails to boot on x3850x5 machine

[Thomas Gleixner <tglx@linutronix.de>]

On Wed, 14 Dec 2011, Nikunj A Dadhania wrote:

> Hi,
> 
> I was trying the latest tip kernel and I am seeing the following
> message. After some more logs the machine does not proceed.
> 
> ------------[ cut here ]------------
> WARNING: at kernel/time/clockevents.c:47 clockevent_delta2ns+0x79/0x90()

Ok, that's caused by stupidity in the apic timer code. Fix
below. Note, that patch wont fix the boot problem. It just prevents
the warning.

> Hardware name: System x3850 X5 -[71455RQ]-
> Modules linked in:
> Pid: 1, comm: swapper/0 Not tainted 3.2.0-rc4-tip #3
> Call Trace:
>  [<ffffffff8104d3af>] warn_slowpath_common+0x7f/0xc0
>  [<ffffffff8104d40a>] warn_slowpath_null+0x1a/0x20
>  [<ffffffff81097ab9>] clockevent_delta2ns+0x79/0x90
>  [<ffffffff81e49109>] calibrate_APIC_clock+0x16e/0x377
>  [<ffffffff81e4942c>] setup_boot_APIC_clock+0x59/0x7e
>  [<ffffffff81e472d1>] native_smp_prepare_cpus+0x1f1/0x205
>  [<ffffffff81e38767>] kernel_init+0x1b6/0x29a
>  [<ffffffff815f9ca4>] kernel_thread_helper+0x4/0x10
>  [<ffffffff81e385b1>] ? parse_early_options+0x20/0x20
>  [<ffffffff815f9ca0>] ? gs_change+0x13/0x13
> ---[ end trace a7919e7f17c0a725 ]---
> APIC frequency too slow, disabling apic timer

Ouch. This is really bad.

> Performance Events: PEBS fmt1+, Nehalem events, Intel PMU driver.
> CPU erratum AAJ80 worked around
> CPUID marked event: 'bus cycles' unavailable
> ... version:                3
> ... bit width:              48
> ... generic registers:      4
> ... value mask:             0000ffffffffffff
> ... max period:             000000007fffffff
> ... fixed-purpose events:   3
> ... event mask:             000000070000000f
> NMI watchdog enabled, takes one hw-pmu counter.
> Booting Node   0, Processors  #1
> APIC never delivered???
> APIC delivery error (ef).
>  #2

And probably caused by non working APIC. From your log:
 
 weird, boot CPU (#255) not listed by the BIOS.
 LAPIC pending interrupts after 512 EOI

Can you please provide a full boot log up to the point of

Booting Node   0, Processors  #1

Your log is missing the head of the boot process. Can you also add
"apic=verbose" to the kernel command line please ?

Thanks,

	tglx

---------->
diff --git a/arch/x86/kernel/apic/apic.c b/arch/x86/kernel/apic/apic.c
index 39e3eaa..35a5b31 100644
--- a/arch/x86/kernel/apic/apic.c
+++ b/arch/x86/kernel/apic/apic.c
@@ -696,6 +696,18 @@ static int __init calibrate_APIC_clock(void)
 	pm_referenced = !calibrate_by_pmtimer(lapic_cal_pm2 - lapic_cal_pm1,
 					&delta, &deltatsc);
 
+
+	lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
+
+	/*
+	 * Do a sanity check on the APIC calibration result
+	 */
+	if (lapic_timer_frequency < (1000000 / HZ)) {
+		local_irq_enable();
+		pr_warning("APIC frequency too slow, disabling apic timer\n");
+		return -1;
+	}
+
 	/* Calculate the scaled math multiplication factor */
 	lapic_clockevent.mult = div_sc(delta, TICK_NSEC * LAPIC_CAL_LOOPS,
 				       lapic_clockevent.shift);
@@ -704,8 +716,6 @@ static int __init calibrate_APIC_clock(void)
 	lapic_clockevent.min_delta_ns =
 		clockevent_delta2ns(0xF, &lapic_clockevent);
 
-	lapic_timer_frequency = (delta * APIC_DIVISOR) / LAPIC_CAL_LOOPS;
-
 	apic_printk(APIC_VERBOSE, "..... delta %ld\n", delta);
 	apic_printk(APIC_VERBOSE, "..... mult: %u\n", lapic_clockevent.mult);
 	apic_printk(APIC_VERBOSE, "..... calibration result: %u\n",
@@ -723,15 +733,6 @@ static int __init calibrate_APIC_clock(void)
 		    lapic_timer_frequency / (1000000 / HZ),
 		    lapic_timer_frequency % (1000000 / HZ));
 
-	/*
-	 * Do a sanity check on the APIC calibration result
-	 */
-	if (lapic_timer_frequency < (1000000 / HZ)) {
-		local_irq_enable();
-		pr_warning("APIC frequency too slow, disabling apic timer\n");
-		return -1;
-	}
-
 	levt->features &= ~CLOCK_EVT_FEAT_DUMMY;
 
 	/*