trace_printk schedules work via irq_work_queue(), but doesn't wait until it was processed. The kprobe_module.tc testcase does: :;: "Load module again, which means the event1 should be recorded";: modprobe trace-printk grep "event1:" trace so the grep which checks the trace file might run before the irq work was processed. Fix this by adding a irq_work_sync(). Signed-off-by: Sven Schnelle <svens@xxxxxxxxxxxxx> --- samples/trace_printk/trace-printk.c | 1 + 1 file changed, 1 insertion(+) diff --git a/samples/trace_printk/trace-printk.c b/samples/trace_printk/trace-printk.c index 7affc3b50b61..cfc159580263 100644 --- a/samples/trace_printk/trace-printk.c +++ b/samples/trace_printk/trace-printk.c @@ -36,6 +36,7 @@ static int __init trace_printk_init(void) /* Kick off printing in irq context */ irq_work_queue(&irqwork); + irq_work_sync(&irqwork); trace_printk("This is a %s that will use trace_bprintk()\n", "static string"); -- 2.17.1