Fujitsu lifebook A544, after bios update, kacpid using processor

[Colin Law]

On Sun, 26 Jul 2020 at 14:42, Colin Law <clanlaw at gmail.com> wrote:
>
> I booted into Windows on my Fujitsu Lifebook A544 and was notified
> that there was an important BIOS upgrade which would make it less
> likely that my battery would self ignite, so I upgraded it to the
> latest (1.25).  Now, however, in Ubuntu, the system monitor shows that
> something is permanently using about 60% of one of the cores, but the
> process list shows nothing using anything like that amount of
> processor.
> Using htop and hitting K, which I think then shows kernel threads, it
> appears to show that the culprits are kworkers kacpid, kacpi_notify.
> Googling suggests that others with similar problems have solved it by
> various means including installing acpi (no difference) and adding
> kernel parameter noapic (which made it worse).  Has anyone any other
> ideas which might help?

I should have said - this is Ubuntu 20.04 up to date

Colin