Re: [PATCH v3] ACPI: scan: Avoid registering platform devices with resource overlaps

[Rafael J. Wysocki (Intel)]

On Wed, Aug 19, 2026 at 9:46 AM Andy Shevchenko
<andriy.shevchenko@xxxxxxxxxxxxxxx> wrote:
>
> On Tue, Aug 18, 2026 at 05:37:52PM -0700, Nathan Chancellor wrote:
> > On Fri, Aug 07, 2026 at 12:22:37PM +0200, Rafael J. Wysocki wrote:
> > >
> > > If acpi_dev_get_resources() returns overlapping I/O or memory resources,
> > > the subsequent registration of a platform device will fail with -EBUSY
> > > due to a resource conflict.  This is reported to happen on Acer Aspire
> > > ES1-572 [1].
> > >
> > > Avoid that by adjusting resources returned by acpi_dev_get_resources()
> > > to eliminate partial overlaps between them.
> > >
> > > This has not been regarded as necessary before because putting
> > > overlapping resources into the _CRS of one device is really pointless,
> > > but now that the issue has been reported to actually happen in the
> > > field, it needs to be done.
> > >
> > > Fixes: ab06eb920401 ("ACPI: scan: Register platform devices for fixed event buttons")
> > > Reported-by: Julien <julien82453@xxxxxxxxx>
> > > Closes: https://lore.kernel.org/linux-integrity/CAJOGg3z6LJPDsdPNBxajgy8_wQxfhYBRxe4EiurZf3kPU5A5Bw@xxxxxxxxxxxxxx/ [1]
> >
> > I bisected the following kernel message that I see on one of my aarch64
> > test machines to this change in -next as commit f234fdaae1ca ("ACPI:
> > scan: Avoid registering platform devices with resource overlaps"):
> >
> >   arm-cmn ARMHC600:00: probe with driver arm-cmn failed with error -22
> >
> > Is this expected? If not, what information would be helpful for debugging this?
>
> Looks like a mess in _CRS. You can share dsdt.dsl to see if the resource
> conflict is visible from there.

Well, so long as the device is defined in the DSDT.

>
> Does anything stop working?

Apparently, a driver is not probing any more ...