Temporary fix for ACPI (GPE iinterrupts) failure , disable GPE6f interrupts, probably motherboard faulty ACPI implementation (reflash/update BIOS) [[!!You should take action!!]]. Install this in /usr/lib/systemd/system and run systemctl enable disable_gpe6F

disable_gpe6F.service

[Unit]
Description=Disable GPE6F interrupts

[Service]
Type=oneshot
ExecStart=/bin/bash -c "echo disable > /sys/firmware/acpi/interrupts/gpe6F"

[Install]
WantedBy=multi-user.target

Additional helpful note for potential future readers: if BIOS update does not solve issue, you can either keep this systemd service or add acpi_mask_gpe=0x6F as kernel boot parameter.

In my experience, this issue is reflected in 20-30% of CPU usage for the Linux kworker process or for the System process on a Windows machine.
Also, this approach is useful for any interrupts that might be hogging your CPU, use grep . -r /sys/firmware/acpi/interrupts/ to find out.

After 8 years the problem obviously still persist on some devices.
I've updated the BIOS on my HP ZBook G6 recently and now the Arch Linux installation is running in this trouble with 6F.

I've read somewhere it has something to do with a connected USB device which is missing and the 6F is waiting for it, causing the CPU load

Tried to disable it via GRUB, but that is not working in 50% of the time after reboot. Sometimes works, sometimes not.
Installed it now as a service, let's see how this goes.