Project

General

Profile

Actions

Bug #1315

open

Kernel panics after `pkill lttng`; root session daemon has active triggers

Added by Philippe Proulx about 1 year ago. Updated about 1 year ago.

Status:
Feedback
Priority:
Normal
Target version:
-
Start date:
05/07/2021
Due date:
% Done:

0%

Estimated time:

Description

I don't know how to reproduce this bug.

I played with the lttng add-trigger command while writing usage examples for its manual page.

I started the root session daemon as such:

# lttng-sessiond --daemonize --group=eepp

I then ran commands such as:

$ lttng add-trigger --name user --condition=event-rule-matches --domain=user --action=notify
$ lttng add-trigger --condition=event-rule-matches \
                    --domain=user --action=notify \
                    --rate-policy=every:10
$ lttng add-trigger --owner-uid=33 \
                    --condition=event-rule-matches \
                    --domain=kernel --name='sched*' \
                    --action=notify
$ lttng add-trigger --condition=event-rule-matches \
                    --domain=kernel --type=syscall \
                    --filter='fd < 3' \
                    --action=start-session my-session \
                    --rate-policy=once-after:40

Note that I had no tracing session named my-session.

After a few minutes, Xorg froze. I managed to login again in a virtual console. I ran:

# pkill lttng

and got an instant kernel panic.

Attached is a photo of what was on the screen after running pkill.

Using:

  • LTTng-tools 60860e547ce31ea629e846e00b66342425474b8d.
  • LTTng-UST a0f2513af262a19822d46f84cd5e34be0badc484
  • LTTng-modules 51ef453614a6db2b778595b16d93283d25db974a
  • liburcu 5e1b7c840a2b21b8442b322cedbb70a790e49520

Files

IMG-5047.jpg (3.47 MB) IMG-5047.jpg Kernel panic photo Philippe Proulx, 05/07/2021 04:04 PM
Actions

Also available in: Atom PDF