On Fri, Aug 7, 2026 at 2:57 PM Paul Menzel <[email protected]> wrote:
>
> Dear Rafael,
>
>
> Thank you for the patch.
>
> Am 07.08.26 um 12:22 schrieb Rafael J. Wysocki:
> > From: "Rafael J. Wysocki" <[email protected]>
> >
> > 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].
>
> Reading the diff, it might be useful to paste the log warning already here:
>
> tpm_crb_acpi MSFT0101:00: [Firmware Bug]: Bad ACPI memory layout
It's there in the message pointed to by the Closes: tag though.
> > 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 <[email protected]>
> > Closes:
> > https://lore.kernel.org/linux-integrity/cajogg3z6ljpdsdpnbxajgy8_wqxfhybrxe4eiurzf3kpu5a...@mail.gmail.com/
> > [1]
> > Cc: All applicable <[email protected]>
> > Signed-off-by: Rafael J. Wysocki <[email protected]>
> > ---
> >
> > v2 -> v3:
> > * Use resource_union() and adjust code and comment (Andy)
> > * Include ioport.h directly
> >
> > v1 -> v2:
> > * Add the expanded resource instead of and not in addition to the other
> > overlapping one (Sashiko)
> >
> > ---
> > drivers/acpi/acpi_platform.c | 39
> > +++++++++++++++++++++++++++++++++++++--
> > 1 file changed, 37 insertions(+), 2 deletions(-)
> >
> > --- a/drivers/acpi/acpi_platform.c
> > +++ b/drivers/acpi/acpi_platform.c
> > @@ -12,6 +12,7 @@
> > #include <linux/bits.h>
> > #include <linux/device.h>
> > #include <linux/err.h>
> > +#include <linux/ioport.h>
> > #include <linux/kernel.h>
> > #include <linux/module.h>
> > #include <linux/dma-mapping.h>
> > @@ -71,6 +72,36 @@ static struct notifier_block acpi_platfo
> > .notifier_call = acpi_platform_device_remove_notify,
> > };
> >
> > +static unsigned int acpi_platform_adjust_resources(struct acpi_device
> > *adev,
> > + struct resource *new_res,
> > + struct resource *resources,
> > + unsigned int count)
> > +{
> > + unsigned int i;
> > +
> > + if (!(new_res->flags & (IORESOURCE_IO | IORESOURCE_MEM)))
> > + return count;
> > +
> > + for (i = 0; i < count; ) {
> > + struct resource *res = &resources[i];
> > +
> > + if (resource_type(new_res) != resource_type(res) ||
> > + !resource_union(new_res, res, new_res)) {
> > + i++;
> > + continue;
> > + }
> > +
> > + dev_info(&adev->dev, "%pR expanded to avoid overlap\n",
> > new_res);
>
> Maybe more normal user understandable:
>
> %pR expanded to fit all resources to avoid overlap
What about "expanded due to overlap"? I'd prefer it to be shorter
because the resource printout takes up some message space already.
> For the record, Julian reported that now the lines below are logged:
>
> MSFT0101:00: [mem 0xfed40000-0xfed4103f] expanded to avoid overlap
> tpm_crb_acpi MSFT0101:00: [Firmware Bug]: Bad ACPI memory layout
Right, and the second one comes from the driver binding to the device.
> > + /*
> > + * Eliminate the previously processed resource that overlapped
> > + * with the new one because it is not necessary any more.
> > + */
> > + memmove(res, res + 1, (--count - i) * sizeof(*res));
> > + }
> > +
> > + return count;
> > +}
> > +
> > static void acpi_platform_fill_resource(struct acpi_device *adev,
> > const struct resource *src, struct resource *dest)
> > {
> > @@ -151,10 +182,14 @@ struct platform_device *acpi_create_plat
> > return ERR_PTR(-ENOMEM);
> > }
> > count = 0;
> > - list_for_each_entry(rentry, &resource_list, node)
> > + list_for_each_entry(rentry, &resource_list, node) {
> > + count = acpi_platform_adjust_resources(adev,
> > +
> > rentry->res,
> > +
> > resources,
> > + count);
> > acpi_platform_fill_resource(adev, rentry->res,
> >
> > &resources[count++]);
> > -
> > + }
> > acpi_dev_free_resource_list(&resource_list);
> > }
> > }
>
> Reviewed-by: Paul Menzel <[email protected]>
Thank you!
