When playing with trace_user_trigger_irq in order to trace IRQ->userspace latencies, I encountered a bug in the latency tracer. If I have wakeup_timing enabled and attempt to stop the trace in my userspace program, the system crashes. This is caused by an unbalanced preempt_enable() which underflows the preempt count.
Signed-off-by: Michal Schmidt <[EMAIL PROTECTED]> diff --git a/kernel/latency_trace.c b/kernel/latency_trace.c index e07bb95..29dfb79 100644 --- a/kernel/latency_trace.c +++ b/kernel/latency_trace.c @@ -2396,7 +2396,6 @@ long user_trace_stop(void) if (current != sch.task) { __raw_spin_unlock(&sch.trace_lock); local_irq_restore(flags); - preempt_enable(); return -EINVAL; } sch.task = NULL; - 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/