For info, I have same symptoms as OP (Aceland Kao) reported (same perf report), on Ubuntu 16.04 with Kernel 4.4.0-59.80 generic. This is on a laptop (HP EliteBook G1 480) on a docking station.
I could apparently fix the problem by undocking and docking back the laptop while still powered. Actually the problem appeared while docking the laptop when sleeping, then waking up. To be exact, here the complete sequence I followed: - Dock the PC, and wake it up. - Notice the CPU usage, and start 'perf' to debug - Undock the PC - Plug many USB devices in all ports. No effect. - Remove the USB devices. - Close the lid (for suspend), then open it again. No effect. - Dock back the PC (when powered up) --> problem when away. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1488426 Title: High CPU usage of kworker/ksoftirqd To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1488426/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
