> i have no better ideas that what you already tried - but unfortunately > the tracer makes the bug go away and the NMI watchdog crashes your box. > Btw., nmi_watchdog=2 might have a higher chance of surviving (it can > still lock up a T60 but with a lower likelyhood).
Good tip, nmi_watchdog=2 worked. Unlike the previous freezes, after this one it didn't continue after some minutes. Don't know if that's because the NMI oopser changed something, or if this is a slightly different lockup... No serial port on this laptop, so screenshot done with digicam: http://www.kernel.org/pub/linux/kernel/people/mszeredi/freeze/nmioops.jpg Here are the transcribed stack traces: CPU1 process: strace _spin_lock task_rq_lock wait_task_inactive ptrace_check_attach sys_ptrace CPU0 process: fusexmp_fh (this is one of several similar threads being straced) _spin_lock_irq schedule ptrace_stop ptrace_notify syscall_trace syscall_trace_enter tracesys Both these seem to be spinning on rq->lock, but who is holding this lock? Miklos - 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/