Re: [PATCH] x86/acpi: Work around broken XSDT on SEGA AALE board

[Rafael J. Wysocki]

On Tue, Mar 1, 2022 at 8:34 PM Rafael J. Wysocki <rafael@xxxxxxxxxx> wrote:
>
> On Thu, Feb 24, 2022 at 9:41 AM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
> >
> > Hi Mark,
> >
> > On 2/23/22 17:07, Mark Cilissen wrote:
> > > On this board the ACPI RSDP structure points to both a RSDT and an XSDT,
> > > but the XSDT points to a truncated FADT. This causes all sorts of trouble
> > > and usually a complete failure to boot after the following error occurs:
> > >
> > >   ACPI Error: Unsupported address space: 0x20 (*/hwregs-*)
> > >   ACPI Error: AE_SUPPORT, Unable to initialize fixed events (*/evevent-*)
> > >   ACPI: Unable to start ACPI Interpreter
> > >
> > > This leaves the ACPI implementation in such a broken state that subsequent
> > > kernel subsystem initialisations go wrong, resulting in among others
> > > mismapped PCI memory, SATA and USB enumeration failures, and freezes.
> > >
> > > As this is an older embedded platform that will likely never see any BIOS
> > > updates to address this issue and its default shipping OS only complies to
> > > ACPI 1.0, work around this by forcing `acpi=rsdt`. This patch, applied on
> > > top of Linux 5.10.102, was confirmed on real hardware to fix the issue.
> > >
> > > Signed-off-by: Mark Cilissen <mark@xxxxxxxxxx>
> > > Cc: stable@xxxxxxxxxxxxxxx
> >
> > Wow, you got it working, cool!
> >
> > The patch looks good to me:
> >
> > Reviewed-by: Hans de Goede <hdegoede@xxxxxxxxxx>
>
> Applied as 5.18 material, thanks!

And dropped due to a problem introduced by it.

Also please note that the x86 mailing list address originally used in
the CC list was incorrect.