The pr_crap() functions generate idiotic output; use printk(). Broken output: [ 3538.718135] NMI watchdog: BUG: soft lockup - CPU#2 stuck for 22s! [perf_fuzzer:2646] [ 3383.233583] NMI watchdog: Watchdog detected hard LOCKUP on cpu 27 Fixed output: [14180.328194] BUG: soft lockup - CPU#2 stuck for 23s! [perf_fuzzer:13650] [ 1064.914925] BUG: NMI Watchdog detected hard LOCKUP on cpu 11 Cc: Don Zickus Signed-off-by: Peter Zijlstra (Intel) --- kernel/watchdog.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) --- a/kernel/watchdog.c +++ b/kernel/watchdog.c @@ -350,7 +350,7 @@ static void watchdog_overflow_callback(s if (__this_cpu_read(hard_watchdog_warn) == true) return; - pr_emerg("Watchdog detected hard LOCKUP on cpu %d", this_cpu); + printk(KERN_EMERG "BUG: NMI detected hard LOCKUP on cpu %d", this_cpu); print_modules(); print_irqtrace_events(current); if (regs) @@ -467,7 +467,7 @@ static enum hrtimer_restart watchdog_tim } } - pr_emerg("BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", + printk(KERN_EMERG "BUG: soft lockup - CPU#%d stuck for %us! [%s:%d]\n", smp_processor_id(), duration, current->comm, task_pid_nr(current)); __this_cpu_write(softlockup_task_ptr_saved, current);