From: Li Zhong <[email protected]> In tick_nohz_cpu_down_callback() if the cpu is the one handling timekeeping , we must return something that stops the CPU_DOWN_PREPARE notifiers and then start notify CPU_DOWN_FAILED on the already called notifier call backs.
However traditional errno values are not handled by the notifier unless these are encapsulated using errno_to_notifier(). Hence the current -EINVAL is misinterpreted and converted to junk after notifier_to_errno(), leaving the notifier subsystem to random behaviour such as eventually allowing the cpu to go down. Fix this by using the standard NOTIFY_BAD instead. Signed-off-by: Li Zhong <[email protected]> Reviewed-by: Srivatsa S. Bhat <[email protected]> Cc: Steven Rostedt <[email protected]> Cc: Paul E. McKenney <[email protected]> Cc: Ingo Molnar <[email protected]> Cc: Thomas Gleixner <[email protected]> Cc: Peter Zijlstra <[email protected]> Cc: Borislav Petkov <[email protected]> Signed-off-by: Frederic Weisbecker <[email protected]> --- kernel/time/tick-sched.c | 2 +- 1 files changed, 1 insertions(+), 1 deletions(-) diff --git a/kernel/time/tick-sched.c b/kernel/time/tick-sched.c index cfc798b..58d8d4d 100644 --- a/kernel/time/tick-sched.c +++ b/kernel/time/tick-sched.c @@ -311,7 +311,7 @@ static int __cpuinit tick_nohz_cpu_down_callback(struct notifier_block *nfb, * we can't safely shutdown that CPU. */ if (have_nohz_full_mask && tick_do_timer_cpu == cpu) - return -EINVAL; + return NOTIFY_BAD; break; } return NOTIFY_OK; -- 1.7.5.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
