** Also affects: linux (Ubuntu Zesty) Importance: Medium Assignee: dann frazier (dannf) Status: In Progress
** Also affects: linux (Ubuntu Yakkety) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Zesty) Status: In Progress => Fix Released ** Changed in: linux (Ubuntu Yakkety) Status: New => In Progress ** Changed in: linux (Ubuntu Yakkety) Assignee: (unassigned) => dann frazier (dannf) -- You received this bug notification because you are a member of Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1634271 Title: arm64: kprobes disabled Status in linux package in Ubuntu: Fix Released Status in linux source package in Yakkety: In Progress Status in linux source package in Zesty: Fix Released 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_KPROBE_EVENTS. 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_fault_handler() - but only in the case that this newly enabled feature is being used (if kprobe_running()). To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1634271/+subscriptions -- Mailing list: https://launchpad.net/~kernel-packages Post to : kernel-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~kernel-packages More help : https://help.launchpad.net/ListHelp