[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>

1 files changed, 3 insertions, 1 deletions

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();