Commit b884e257 authored Mar 07, 2006 by GOTO Masanori Committed by Linus Torvalds Mar 08, 2006

[PATCH] x86: Fix i386 nmi_watchdog that does not trigger die_nmi



Fix i386 nmi_watchdog that does not meet watchdog timeout condition.  It
does not hit die_nmi when it should be triggered, because the current
nmi_watchdog_tick in arch/i386/kernel/nmi.c never count up alert_counter
like this:

	void nmi_watchdog_tick (struct pt_regs * regs) {
	if (last_irq_sums[cpu] == sum) {
		alert_counter[cpu]++;		<- count up alert_counter, but
		if (alert_counter[cpu] == 5*nmi_hz)
			die_nmi(regs, "NMI Watchdog detected LOCKUP");
		alert_counter[cpu] = 0;		<- reset alert_counter

This patch changes it back to the previous and working version.

This was found and originally written by Kohta NAKASHIMA.

(akpm: also uninline write_watchdog_counter(), saving 184 byets)

Signed-off-by: GOTO Masanori <gotom@sanori.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

parent 707ced0d

arch/i386/kernel/nmi.c

+2 −2

Original line number	Diff line number	Diff line
		@@ -357,7 +357,7 @@ static void clear_msr_range(unsigned int base, unsigned int n)
		wrmsr(base+i, 0, 0);
		}

		static inline void write_watchdog_counter(const char *descr)
		static void write_watchdog_counter(const char *descr)
		{
		u64 count = (u64)cpu_khz * 1000;

		@@ -544,7 +544,7 @@ void nmi_watchdog_tick (struct pt_regs * regs)
		* die_nmi will return ONLY if NOTIFY_STOP happens..
		*/
		die_nmi(regs, "NMI Watchdog detected LOCKUP");

		} else {
		last_irq_sums[cpu] = sum;
		alert_counter[cpu] = 0;
		}