Re: [PATCH 0/6] Support calling functions on dedicated physical cpu

From: One Thousand Gnomes
Date: Fri Mar 11 2016 - 08:17:32 EST


On Fri, 11 Mar 2016 13:25:14 +0100
Peter Zijlstra <peterz@xxxxxxxxxxxxx> wrote:

> On Fri, Mar 11, 2016 at 12:59:28PM +0100, Juergen Gross wrote:
> > Some hardware (e.g. Dell Studio laptops) require special functions to
> > be called on physical cpu 0 in order to avoid occasional hangs. When
> > running as dom0 under Xen this could be achieved only via special boot
> > parameters (vcpu pinning) limiting the hypervisor in it's scheduling
> > decisions.
>
> So instead of telling Dell to get their act together and fix their damn
> firmware, we're going to add the most horrid gunk to the kernel? How
> does that make sense?

It's been normal forever. The convention with a lot of older BIOS crap
was always that it should be called on the boot CPU (APM. PnPBIOS etc).

It's a stretch pre-EFI to even call it a "bug"

Alan