arm64: kprobes disabled
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Fix Released
|
Medium
|
dann frazier | ||
Yakkety |
Fix Released
|
Undecided
|
dann frazier | ||
Zesty |
Fix Released
|
Medium
|
dann frazier |
Bug Description
[Impact]
kprobes is currently enabled for all Ubuntu architectures except arm64. This excludes a useful debug feature, which is required by certain userspace provided by Ubuntu, such as perf's probe command. I failed to notice this in my yakkety config review because it is a new feature in v4.8.
[Test Case]
= Failure case =
ubuntu@arm64:~$ sudo perf probe schedule
kprobe_events file does not exist - please rebuild kernel with CONFIG_
Error: Failed to add events.
= Success case =
ubuntu@arm64:~$ sudo perf probe schedule
Added new event:
probe:schedule (on schedule)
You can now use it in all perf tools, such as:
perf record -e probe:schedule -aR sleep 1
ubuntu@arm64:~$ sudo perf record -e probe:schedule -aR sleep 1
[ perf record: Woken up 1 times to write data ]
[ perf record: Captured and wrote 0.185 MB perf.data (61 samples) ]
[Regression Risk]
The proposed fix enables a config for an already-upstream feature, so regressions will have upstream support. The config change mostly results in building new code vs. modifying existing code. The notable exception is that arm64's notify_page_fault() will now get code to call kprobe_
CVE References
description: | updated |
Changed in linux (Ubuntu Zesty): | |
status: | In Progress → Fix Released |
Changed in linux (Ubuntu Yakkety): | |
assignee: | nobody → dann frazier (dannf) |
status: | New → In Progress |
Changed in linux (Ubuntu Yakkety): | |
status: | In Progress → Fix Committed |
tags: |
added: verification-done-yakkety removed: verification-needed-yakkety |
This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification- needed- yakkety' to 'verification- done-yakkety' .
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.
See https:/ /wiki.ubuntu. com/Testing/ EnableProposed for documentation how to enable and use -proposed. Thank you!