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 Kernel Packages, which is subscribed to linux in Ubuntu. https://bugs.launchpad.net/bugs/1488426 Title: High CPU usage of kworker/ksoftirqd Status in HWE Next: New Status in linux package in Ubuntu: In Progress Bug description: kworker consuming 71.5% cpu resource ksoftirqd consuming 28.9% cpu resource It leads to power consumption issue and sometimes leads to BT does not work. To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1488426/+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
