I think this patch can get this issue fixed on Cosmic: https://github.com/torvalds/linux/commit/43a1b0cb4cd6dbfd3cd9c10da663368394d299d8 (found in this thread https://lkml.org/lkml/2018/12/3/1219)
Test kernel: http://people.canonical.com/~phlin/kernel/lp-1826385-ftrace-hang/ Cosmic KVM and bare-metal passed the ftrace test with this test kernel. The commit that fixed by this patch has already landed in Cosmic for a while, for now I can't tell why this was only gets triggered recently and why this is not failing in the last cycle. (The gcc version in the last cycle is already 8, 4:8.3.0-1ubuntu1.1 from -proposed.) ** Also affects: linux (Ubuntu Cosmic) Importance: Undecided Status: New -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1826385 Title: ftrace in ubuntu_kernel_selftests hang with Cosmic kernel To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-kernel-tests/+bug/1826385/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
