Re: [REGRESSION] PCI/AER: MacBookPro16,1 powers off ~20 s after boot

[Lukas Wunner]

On Tue, Oct 06, 2026 at 12:37:18PM -0400, Alex Deucher wrote:
> On Mon, Oct 5, 2026 at 7:19 PM Bjorn Helgaas <helgaas@xxxxxxxxxx> wrote:
> > Alex reported something similar at
> > https://bugzilla.kernel.org/show_bug.cgi?id=222095.
> 
> Lukas' patches fixes some boards, but unfortunately, I'm still seeing
> failures on others.  Reverting the patch fixes those failures.  I've
> updated the ticket.

I've added an analysis of the dmesg output as well as a patch.
It looks like the BIOS is raising a false alarm in that it signals
a Fatal Error even though the Uncorrectable Error Status register is
blank.  The patch causes such events to be reported, but otherwise
ignored (i.e. no recovery is attempted for a false alarm).

Newly enabled functionality like Advisory Non-Fatal Errors causes
BIOS code paths to be exercised which likely haven't been tested
by firmware validation folks, hence the fallout.  However I believe
ultimately we *want* to see those errors being reported because they
may point to BIOS issues which flew under the radar so far.

Thanks,

Lukas