Hi Harish, excuse me, but you are using a very old and in between outdated kernel with 4.15.0-29
With bionic/18.04 we are today at 4.15.0.72: linux-generic | 4.15.0.20.23 | bionic | s390x (initial kernel, already superseded) linux-generic | 4.15.0.72.74 | bionic-security | s390x <== linux-generic | 4.15.0.72.74 | bionic-updates | s390x <== linux-generic | 4.15.0.73.75 | bionic-proposed | s390x (and even have 4.15.0.73 in proposed). I also looked up the 3 commit IDs - you've mentioned above - in bionic's git tree, and they are all in since a couple of kernel updates: 1) "Disable preemption after queueing stopper threads" Ubuntu-4.15.0-48.51 Ubuntu-4.15.0-49.52 Ubuntu-4.15.0-49.53 Ubuntu-4.15.0-50.54 Ubuntu-4.15.0-51.55 Ubuntu-4.15.0-52.56 Ubuntu-4.15.0-54.58 Ubuntu-4.15.0-55.60 Ubuntu-4.15.0-56.62 Ubuntu-4.15.0-57.63 Ubuntu-4.15.0-58.64 Ubuntu-4.15.0-59.66 Ubuntu-4.15.0-60.67 Ubuntu-4.15.0-62.69 Ubuntu-4.15.0-64.73 Ubuntu-4.15.0-65.74 Ubuntu-4.15.0-66.75 Ubuntu-4.15.0-67.76 Ubuntu-4.15.0-68.77 Ubuntu-4.15.0-69.78 Ubuntu-4.15.0-70.79 Ubuntu-4.15.0-71.80 Ubuntu-4.15.0-72.81 2) "Disable preemption when waking two stopper threads" Ubuntu-4.15.0-46.49 Ubuntu-4.15.0-47.50 Ubuntu-4.15.0-48.51 Ubuntu-4.15.0-49.52 Ubuntu-4.15.0-49.53 Ubuntu-4.15.0-50.54 Ubuntu-4.15.0-51.55 Ubuntu-4.15.0-52.56 Ubuntu-4.15.0-54.58 Ubuntu-4.15.0-55.60 Ubuntu-4.15.0-56.62 Ubuntu-4.15.0-57.63 Ubuntu-4.15.0-58.64 Ubuntu-4.15.0-59.66 Ubuntu-4.15.0-60.67 Ubuntu-4.15.0-62.69 Ubuntu-4.15.0-64.73 Ubuntu-4.15.0-65.74 Ubuntu-4.15.0-66.75 Ubuntu-4.15.0-67.76 Ubuntu-4.15.0-68.77 Ubuntu-4.15.0-69.78 Ubuntu-4.15.0-70.79 Ubuntu-4.15.0-71.80 Ubuntu-4.15.0-72.81 3) "sched: Fix migrate_swap() vs. active_balance() deadlock" Ubuntu-4.15.0-37.40 Ubuntu-4.15.0-38.41 Ubuntu-4.15.0-39.42 Ubuntu-4.15.0-40.43 Ubuntu-4.15.0-42.45 Ubuntu-4.15.0-43.46 Ubuntu-4.15.0-44.47 Ubuntu-4.15.0-45.48 Ubuntu-4.15.0-46.49 Ubuntu-4.15.0-47.50 Ubuntu-4.15.0-48.51 Ubuntu-4.15.0-49.52 Ubuntu-4.15.0-49.53 Ubuntu-4.15.0-50.54 Ubuntu-4.15.0-51.55 Ubuntu-4.15.0-52.56 Ubuntu-4.15.0-54.58 Ubuntu-4.15.0-55.60 Ubuntu-4.15.0-56.62 Ubuntu-4.15.0-57.63 Ubuntu-4.15.0-58.64 Ubuntu-4.15.0-59.66 Ubuntu-4.15.0-60.67 Ubuntu-4.15.0-62.69 Ubuntu-4.15.0-64.73 Ubuntu-4.15.0-65.74 Ubuntu-4.15.0-66.75 Ubuntu-4.15.0-67.76 Ubuntu-4.15.0-68.77 Ubuntu-4.15.0-69.78 Ubuntu-4.15.0-70.79 Ubuntu-4.15.0-71.80 Ubuntu-4.15.0-72.81 So please update your system to the very latest bionic kernel (as of today: 4.15.0-72) and retest. It's highly likely that the issue you've mentioned is already solved! ** Changed in: linux (Ubuntu) Status: New => Incomplete ** Changed in: ubuntu-power-systems Status: New => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1855679 Title: Rcu stalls and Soft-lockups observed on stressing Ubuntu 18 04 1 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu-power-systems/+bug/1855679/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs