1 files changed, 33 insertions, 17 deletions

diff --git a/arch/i386/kernel/time.c b/arch/i386/kernel/time.c
index 5af802ef00b2..86944acfb647 100644
--- a/arch/i386/kernel/time.c
+++ b/arch/i386/kernel/time.c
@@ -285,16 +285,19 @@ void notify_arch_cmos_timer(void)
         mod_timer(&sync_cmos_timer, jiffies + 1);
 }
 
-static long clock_cmos_diff, sleep_start;
+static long clock_cmos_diff;
+static unsigned long sleep_start;
 
 static int timer_suspend(struct sys_device *dev, pm_message_t state)
 {
         /*
          * Estimate time zone so that set_time can update the clock
          */
-        clock_cmos_diff = -get_cmos_time();
+        unsigned long ctime =  get_cmos_time();
+
+        clock_cmos_diff = -ctime;
         clock_cmos_diff += get_seconds();
-        sleep_start = get_cmos_time();
+        sleep_start = ctime;
         return 0;
 }
 
@@ -302,18 +305,29 @@ static int timer_resume(struct sys_device *dev)
 {
         unsigned long flags;
         unsigned long sec;
-        unsigned long sleep_length;
-
+        unsigned long ctime = get_cmos_time();
+        long sleep_length = (ctime - sleep_start) * HZ;
+        struct timespec ts;
+
+        if (sleep_length < 0) {
+                printk(KERN_WARNING "CMOS clock skew detected in timer resume!\n");
+                /* The time after the resume must not be earlier than the time
+                 * before the suspend or some nasty things will happen
+                 */
+                sleep_length = 0;
+                ctime = sleep_start;
+        }
 #ifdef CONFIG_HPET_TIMER
         if (is_hpet_enabled())
                 hpet_reenable();
 #endif
         setup_pit_timer();
-        sec = get_cmos_time() + clock_cmos_diff;
-        sleep_length = (get_cmos_time() - sleep_start) * HZ;
+
+        sec = ctime + clock_cmos_diff;
+        ts.tv_sec = sec;
+        ts.tv_nsec = 0;
+        do_settimeofday(&ts);
         write_seqlock_irqsave(&xtime_lock, flags);
-        xtime.tv_sec = sec;
-        xtime.tv_nsec = 0;
         jiffies_64 += sleep_length;
         wall_jiffies += sleep_length;
         write_sequnlock_irqrestore(&xtime_lock, flags);
@@ -349,10 +363,11 @@ extern void (*late_time_init)(void);
 /* Duplicate of time_init() below, with hpet_enable part added */
 static void __init hpet_time_init(void)
 {
-        xtime.tv_sec = get_cmos_time();
-        xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
-        set_normalized_timespec(&wall_to_monotonic,
-                -xtime.tv_sec, -xtime.tv_nsec);
+        struct timespec ts;
+        ts.tv_sec = get_cmos_time();
+        ts.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+
+        do_settimeofday(&ts);
 
         if ((hpet_enable() >= 0) && hpet_use_timer) {
                 printk("Using HPET for base-timer\n");
@@ -364,6 +379,7 @@ static void __init hpet_time_init(void)
 
 void __init time_init(void)
 {
+        struct timespec ts;
 #ifdef CONFIG_HPET_TIMER
         if (is_hpet_capable()) {
                 /*
@@ -374,10 +390,10 @@ void __init time_init(void)
                 return;
         }
 #endif
-        xtime.tv_sec = get_cmos_time();
-        xtime.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
-        set_normalized_timespec(&wall_to_monotonic,
-                -xtime.tv_sec, -xtime.tv_nsec);
+        ts.tv_sec = get_cmos_time();
+        ts.tv_nsec = (INITIAL_JIFFIES % HZ) * (NSEC_PER_SEC / HZ);
+
+        do_settimeofday(&ts);
 
         time_init_hook();
 }