On Tue, Nov 27, 2018 at 10:13 AM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote: > Have you tried building a newer kernel with your config and seeing if > that still has it missing? I don't use Ubuntu. Looks like I forgot to hit "reply all" so a couple messages won't appear on the list (silly me)! But, TL;DR I found the problem with a bit of bisection and a bit of reading commits. It came down to this commit on Ubuntu Xenial's HWE 4.13 branch: commit 4ecc04d14ee2f9b46d3e252215a7622d7d47e974 Author: Colin Ian King <colin.king@xxxxxxxxxxxxx> Date: Sat Jan 6 10:26:31 2018 +0000 UBUNTU: SAUCE: BODGE: temporarily disable some kprobe trace points which are cratering Most of the interrupt related trace points are cratering when enabled. Simply turn them off temporarily while we are investigating this. CVE-2017-5754 Based on work by Colin King <colin.king@xxxxxxxxxxxxx> Signed-off-by: Andy Whitcroft <apw@xxxxxxxxxxxxx> Signed-off-by: Kleber Sacilotto de Souza <kleber.souza@xxxxxxxxxxxxx> These tracepoints are still removed as of the latest Ubuntu 4.13 HWE kernel. I tried putting them back, and sure enough cratering ensued, so it looks like my best bet is to try moving forward to a newer kernel. Thanks for the help, Steve! - Trip