mce_timer must be passed to setup_timer() in all cases, no matter whether it is going to be actually used. Otherwise, when the CPU gets brought down, its call to del_timer_sync() will never return, as the timer won't have a base associated, and hence lock_timer_base() will loop infinitely. Signed-off-by: Jan Beulich Cc: --- arch/x86/kernel/cpu/mcheck/mce.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/arch/x86/kernel/cpu/mcheck/mce.c +++ b/arch/x86/kernel/cpu/mcheck/mce.c @@ -1388,13 +1388,14 @@ static void __mcheck_cpu_init_timer( struct timer_list *t = &__get_cpu_var(mce_timer); int *n = &__get_cpu_var(mce_next_interval); + setup_timer(t, mce_start_timer, smp_processor_id()); + if (mce_ignore_ce) return; *n = check_interval * HZ; if (!*n) return; - setup_timer(t, mce_start_timer, smp_processor_id()); t->expires = round_jiffies(jiffies + *n); add_timer_on(t, smp_processor_id()); }