1 files changed, 11 insertions, 0 deletions

diff --git a/kernel/hrtimer.c b/kernel/hrtimer.c
index c2893af9479e..98bee013f71f 100644
--- a/kernel/hrtimer.c
+++ b/kernel/hrtimer.c
@@ -442,6 +442,8 @@ static int hrtimer_reprogram(struct hrtimer *timer,
         ktime_t expires = ktime_sub(timer->expires, base->offset);
         int res;
 
+        WARN_ON_ONCE(timer->expires.tv64 < 0);
+
         /*
          * When the callback is running, we do not reprogram the clock event
          * device. The timer callback is either running on a different CPU or
@@ -452,6 +454,15 @@ static int hrtimer_reprogram(struct hrtimer *timer,
         if (hrtimer_callback_running(timer))
                 return 0;
 
+        /*
+         * CLOCK_REALTIME timer might be requested with an absolute
+         * expiry time which is less than base->offset. Nothing wrong
+         * about that, just avoid to call into the tick code, which
+         * has now objections against negative expiry values.
+         */
+        if (expires.tv64 < 0)
+                return -ETIME;
+
         if (expires.tv64 >= expires_next->tv64)
                 return 0;