it seems to be at-least partly related to the intel driver, I now get following again on busy kworker processes:
cat /proc/228/stack [<ffffffff8106a460>] msleep+0x20/0x30 [<ffffffffa00e6120>] intel_dp_aux_native_read_retry+0xd0/0x140 [i915] [<ffffffffa00e6bfd>] intel_dp_get_dpcd+0x1d/0x60 [i915] [<ffffffffa00e6c5d>] intel_dp_detect_dpcd+0x1d/0x100 [i915] [<ffffffffa00e7ac7>] intel_dp_detect+0x77/0x2d0 [i915] [<ffffffffa00a0922>] drm_helper_hpd_irq_event+0xb2/0x140 [drm_kms_helper] [<ffffffffa00b21eb>] i915_hotplug_work_func+0x8b/0xa0 [i915] [<ffffffff8107677c>] process_one_work+0x15c/0x4d0 [<ffffffff81077fde>] worker_thread+0x16e/0x480 [<ffffffff8107d370>] kthread+0xc0/0xd0 [<ffffffff816d39ec>] ret_from_fork+0x7c/0xb0 [<ffffffffffffffff>] 0xffffffffffffffff However, /sys/module/drm_kms_helper/parameters/poll is "N". It really makes the system completely unusable at random intervals for what seems to be random amounts of time. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/887793 Title: Kworker constantly taking about 100% CPU To manage notifications about this bug go to: https://bugs.launchpad.net/linux/+bug/887793/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
