Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull timer updates from Thomas Gleixner:
 "A rather smalish set of updates for timers and timekeeping:

   - Two core fixes to prevent potential undefinded behaviour about
     which gcc is complaining rightfully.

   - A fix to prevent stopping the tick on an (soon) offline CPU so it
     can complete the shutdown procedure.

   - Wait for clocks to stabilize before making decisions, so a not yet
     validated clock is not rejected.

   - The usual pile of fixes to the various clocksource drivers.

   - Core code typo and include fixlets"

* 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  timekeeping: Include the correct header for errno definitions
  clocksource/drivers/ti-32k: Prevent ftrace recursion
  clocksource/mips-gic-timer: Stop checking cpu_has_counter
  clocksource/mips-gic-timer: Print an error if IRQ setup fails
  tick/nohz: Prevent stopping the tick on an offline CPU
  clocksource/drivers/oxnas: Add OX820 compatible
  clocksource/drivers/timer-atmel-pit: Simplify IRQ handler
  clocksource/drivers/timer-atmel-pit: Remove uselesss WARN_ON_ONCE
  clocksource/drivers/timer-atmel-pit: Drop at91sam926x_pit_common_init
  clocksource/drivers/moxart: Replace panic by pr_err
  clocksource/drivers/moxart: Replace setup_irq by request_irq
  clocksource/drivers/moxart: Add Aspeed support
  clocksource/drivers/moxart: Use struct to hold state
  clocksource/drivers/moxart: Refactor enable/disable
  time: Avoid undefined behaviour in ktime_add_safe()
  time: Avoid undefined behaviour in timespec64_add_safe()
  timekeeping: Prints the amounts of time spent during suspend
  clocksource: Defer override invalidation unless clock is unstable
  hrtimer: Spelling fixes

1 files changed, 5 insertions, 2 deletions

diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c
index 2ec7c00228f3..3bcb61b52f6c 100644
--- a/kernel/time/tick-sched.c
+++ b/kernel/time/tick-sched.c
@@ -186,10 +186,13 @@ static bool check_tick_dependency(atomic_t *dep)
         return false;
 }
 
-static bool can_stop_full_tick(struct tick_sched *ts)
+static bool can_stop_full_tick(int cpu, struct tick_sched *ts)
 {
         WARN_ON_ONCE(!irqs_disabled());
 
+        if (unlikely(!cpu_online(cpu)))
+                return false;
+
         if (check_tick_dependency(&tick_dep_mask))
                 return false;
 
@@ -843,7 +846,7 @@ static void tick_nohz_full_update_tick(struct tick_sched *ts)
         if (!ts->tick_stopped && ts->nohz_mode == NOHZ_MODE_INACTIVE)
                 return;
 
-        if (can_stop_full_tick(ts))
+        if (can_stop_full_tick(cpu, ts))
                 tick_nohz_stop_sched_tick(ts, ktime_get(), cpu);
         else if (ts->tick_stopped)
                 tick_nohz_restart_sched_tick(ts, ktime_get());