Due to the way ftrace works when modifying the code during startup, the NMI watchdog causes too much noise and ftrace can not find a quiet period to instrument the code. Consequently, machines with more than 512 cpus will encounter issues with the NMI watchdog. Such issues will return error messages similar to "BUG: NMI Watchdog detected LOCKUP" and have either 'ftrace_modify_code' or 'ipi_handler' in the backtrace. To work around this issue, disable nmi_watchdog using the command: