On Wed, Nov 09, 2022 at 04:24:21PM +0100, Christophe Fergeau wrote:
> ср, 9 нояб. 2022 г. в 14:32, Mark Brown <broonie@kernel.org>:
> > On Tue, Nov 08, 2022 at 05:30:01PM +0100, Christophe Fergeau wrote:

> > > I've raised this issue with Apple as there's most likely a bug to fix in their
> > > hypervisor, but I was wondering if this could also be worked around kernel-side?
> > > Before this change, I've had no problems with my linux VMs.

> > It should be *possible* to add quirks for this, but there was some
> > sentiment against adding workarounds where the out of spec system could
> > be fixed (unknown registers in the ID space are supposed to be read as
> > zero).

> I haven't heard back from Apple yet. I've tried macOS 13 though, the
> latest macOS major version, and in this version, unpatched kernels
> boot fine, so they probably fixed this out of spec behaviour. It's
> only with macOS 12 that I'm hitting this read_cpuid() failure.
> macOS 13 was released just a few weeks ago, I'm not sure how fast "my"
> users will upgrade, nor if Apple will be willing to backport the fix
> to macOS 12 :-/ Having a workaround for a while would definitely help.

If it's fixed then I'd expect it'd be a struggle to get anything merged
upstream.