From 7aa117bfc27a15bb2656b34bc6322417065a828d Mon Sep 17 00:00:00 2001 From: Sven Schnelle Date: Wed, 18 Dec 2019 08:44:26 +0100 Subject: [PATCH] samples/trace_printk: Wait for IRQ work to finish commit 01f36a554e3ef32f9fc4b81a4437cf08fd0e4742 upstream. 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(). Link: http://lore.kernel.org/linux-trace-devel/20191218074427.96184-3-svens@linux.ibm.com Cc: stable@vger.kernel.org Fixes: af2a0750f3749 ("selftests/ftrace: Improve kprobe on module testcase to load/unload module") Signed-off-by: Sven Schnelle Signed-off-by: Steven Rostedt (VMware) Signed-off-by: Greg Kroah-Hartman --- 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");