Commit 4960c9df authored by Thomas Gleixner's avatar Thomas Gleixner
Browse files

Revert "x86: fix NMI watchdog & 'stopped time' problem" 

This reverts commit d4d25dec.

It tried to fix long standing bugzilla entries, but the solution was
reported to break other systems. The reporter of

http://bugzilla.kernel.org/show_bug.cgi?id=9791



tracked it down to this commit and confirmed that reverting the patch
restores the correct behaviour. It's too late in the release cycle to
find a better solution than reverting the commit to avoid regressions.

Signed-off-by: default avatarThomas Gleixner <tglx@linutronix.de>
Acked-by: default avatarIngo Molnar <mingo@elte.hu>
parent d384e35a

arch/x86/kernel/io_apic_32.c

+2 −10
Original line number Diff line number Diff line
@@ -2169,14 +2169,10 @@ static inline void __init check_timer(void) 
{

	int apic1, pin1, apic2, pin2;

	int vector;

	unsigned int ver;

	unsigned long flags;



	local_irq_save(flags);



	ver = apic_read(APIC_LVR);

	ver = GET_APIC_VERSION(ver);



	/*

	 * get/set the timer IRQ vector:

	 */
@@ -2189,15 +2185,11 @@ static inline void __init check_timer(void) 
	 * mode for the 8259A whenever interrupts are routed

	 * through I/O APICs.  Also IRQ0 has to be enabled in

	 * the 8259A which implies the virtual wire has to be

	 * disabled in the local APIC.  Finally timer interrupts

	 * need to be acknowledged manually in the 8259A for

	 * timer_interrupt() and for the i82489DX when using

	 * the NMI watchdog.

	 * disabled in the local APIC.

	 */

	apic_write_around(APIC_LVT0, APIC_LVT_MASKED | APIC_DM_EXTINT);

	init_8259A(1);

	timer_ack = !cpu_has_tsc;

	timer_ack |= (nmi_watchdog == NMI_IO_APIC && !APIC_INTEGRATED(ver));

	timer_ack = 1;

	if (timer_over_8254 > 0)

		enable_8259A_irq(0);

arch/x86/kernel/nmi_32.c

+2 −7
Original line number Diff line number Diff line
@@ -25,7 +25,6 @@ 


#include <asm/smp.h>

#include <asm/nmi.h>

#include <asm/timer.h>



#include "mach_traps.h"
@@ -84,7 +83,7 @@ static int __init check_nmi_watchdog(void) 


	prev_nmi_count = kmalloc(NR_CPUS * sizeof(int), GFP_KERNEL);

	if (!prev_nmi_count)

		goto error;

		return -1;



	printk(KERN_INFO "Testing NMI watchdog ... ");
@@ -119,7 +118,7 @@ static int __init check_nmi_watchdog(void) 
	if (!atomic_read(&nmi_active)) {

		kfree(prev_nmi_count);

		atomic_set(&nmi_active, -1);

		goto error;

		return -1;

	}

	printk("OK.\n");
@@ -130,10 +129,6 @@ static int __init check_nmi_watchdog(void) 


	kfree(prev_nmi_count);

	return 0;

error:

	timer_ack = !cpu_has_tsc;



	return -1;

}

/* This needs to happen later in boot so counters are working */

late_initcall(check_nmi_watchdog);

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