** Description changed: [Impact] Reading /proc/kcore can lead to a crash on arm64 systems. + This was found to cause crashes when, e.g. annotating symbols in a perf top session. [Test Case] # cat /proc/kcore > /dev/null [Regression Risk] + 2 upstream patches need to be cherry-picked to fix this. + + The 1st patch is a simplification to the kcore driver that impacts all + architectures. Instead of re-checking at read time for vmalloc/module + addresses, it just checks for a flag that was set during kcore driver + init. This looks correct to me but could of course have an unnoticed + bug. + + The second patch is arm64-specific, and regression risk has been + mitigated by testing on arm64 hardware.
** Also affects: linux (Ubuntu Zesty) Importance: Undecided Status: New ** Changed in: linux (Ubuntu Zesty) Status: New => In Progress ** Changed in: linux (Ubuntu) Status: Confirmed => In Progress ** Changed in: linux (Ubuntu Zesty) Assignee: (unassigned) => dann frazier (dannf) ** Changed in: linux (Ubuntu) Importance: Undecided => High ** Changed in: linux (Ubuntu Zesty) Importance: Undecided => High -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1702749 Title: arm64: fix crash reading /proc/kcore To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/linux/+bug/1702749/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs