From 68e188911263adb06e28fa2c9dc9e017774de68d Mon Sep 17 00:00:00 2001
From: Andi Kleen <ak@suse.de>
Date: Mon, 12 Dec 2005 22:17:07 -0800
Subject: [PATCH] [PATCH] x86_64: Make sure hpet_address is 0 when any part of
HPET initialization fails
Otherwise TSC->HPET fallback could see incorrect state and crash later.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
---
arch/x86_64/kernel/time.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
diff --git a/arch/x86_64/kernel/time.c b/arch/x86_64/kernel/time.c
index fdaddc4e5284..4434e154f596 100644
--- a/arch/x86_64/kernel/time.c
+++ b/arch/x86_64/kernel/time.c
@@ -59,7 +59,7 @@ static int notsc __initdata = 0;
unsigned int cpu_khz; /* TSC clocks / usec, not used here */
static unsigned long hpet_period; /* fsecs / HPET clock */
unsigned long hpet_tick; /* HPET clocks / interrupt */
-static int hpet_use_timer;
+static int hpet_use_timer; /* Use counter of hpet for time keeping, otherwise PIT */
unsigned long vxtime_hz = PIT_TICK_RATE;
int report_lost_ticks; /* command line option */
unsigned long long monotonic_base;
@@ -908,6 +908,8 @@ void __init time_init(void)
if (!hpet_init())
vxtime_hz = (1000000000000000L + hpet_period / 2) /
hpet_period;
+ else
+ vxtime.hpet_address = 0;
if (hpet_use_timer) {
cpu_khz = hpet_calibrate_tsc();
--
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