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

[Nathan Chancellor <nathan@kernel.org>]

Hi Rafael,

On Fri, Aug 07, 2026 at 12:22:37PM +0200, Rafael J. Wysocki wrote:
> From: "Rafael J. Wysocki" <rafael.j.wysocki@intel.com>
> 
> 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@gmail.com>
> Closes: https://lore.kernel.org/linux-integrity/CAJOGg3z6LJPDsdPNBxajgy8_wQxfhYBRxe4EiurZf3kPU5A5Bw@mail.gmail.com/ [1]
> Cc: All applicable <stable@vger.kernel.org>
> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

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?

  # bad: [e6664f2b33db9b6811eb4cec109f06cb2b4f458d] Add linux-next specific files for 20260817
  # good: [8d3ae59288f1e7d58d76558a6ee96d533bc5019f] Linux 7.2
  git bisect start 'e6664f2b33db9b6811eb4cec109f06cb2b4f458d' '8d3ae59288f1e7d58d76558a6ee96d533bc5019f'
  # bad: [86de7a3c48ad4465719822b6bfa176c136302e77] Merge branch 'master' of https://git.kernel.org/pub/scm/linux/kernel/git/herbert/cryptodev-2.6.git
  git bisect bad 86de7a3c48ad4465719822b6bfa176c136302e77
  # good: [984aee09cb35477fd7a27fa151e9f8c5a8cb99f9] Merge branch 'xtensa-for-next' of https://github.com/jcmvbkbc/linux-xtensa.git
  git bisect good 984aee09cb35477fd7a27fa151e9f8c5a8cb99f9
  # bad: [d353ba3f585141b91427fb87023e19c1f9ec85cd] Merge branch 'linux-next' of https://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm.git
  git bisect bad d353ba3f585141b91427fb87023e19c1f9ec85cd
  # good: [8bb759cc24c375a265eb6bf2f7c90eb2be20f535] Merge branch 'next' of https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git
  git bisect good 8bb759cc24c375a265eb6bf2f7c90eb2be20f535
  # good: [cdcbf4b274cf62bb9c9f589309315870ddf7250f] Merge branch 'docs-next' of git://git.lwn.net/linux.git
  git bisect good cdcbf4b274cf62bb9c9f589309315870ddf7250f
  # good: [edd0dd59aca038b7f32cf893170928d4a3b2297e] platform: int3472: discrete: Support multiple HIDs per GPIO map entry
  git bisect good edd0dd59aca038b7f32cf893170928d4a3b2297e
  # bad: [cb0428d1dfe236fe8ac926d120a0eb47cdca532e] Merge branch 'pm' into linux-next
  git bisect bad cb0428d1dfe236fe8ac926d120a0eb47cdca532e
  # good: [0c4067b3ff3c8b46076001449f566c4a4f58ede4] Merge branch 'pm-cpuidle'
  git bisect good 0c4067b3ff3c8b46076001449f566c4a4f58ede4
  # good: [02859a576afde166daceffdfb8eefc540fbfff9b] Merge branch 'acpi-irqchip'
  git bisect good 02859a576afde166daceffdfb8eefc540fbfff9b
  # bad: [79ba234b396b0fdcb3a82dd8aa872348f4069aae] Merge branch 'acpi-video'
  git bisect bad 79ba234b396b0fdcb3a82dd8aa872348f4069aae
  # good: [b0572550d83d84fa4d7e9088164ac528c5d82996] Merge back ACPI video bus driver changes for 7.3
  git bisect good b0572550d83d84fa4d7e9088164ac528c5d82996
  # good: [e61487226b7df39e5f4683b036ee6aa7a5039d7b] ACPI: APEI: Handle repeated SEA error storms
  git bisect good e61487226b7df39e5f4683b036ee6aa7a5039d7b
  # bad: [79a0aabd5d800a428ebd412ac1a996a686b53c34] Merge branches 'acpi-scan', 'acpi-pci', 'acpi-tad' and 'acpi-apei'
  git bisect bad 79a0aabd5d800a428ebd412ac1a996a686b53c34
  # good: [a3df8bbe0a704fa5c1609b9666b594f350558fe0] ACPI: TAD: Add locking around AML evaluations
  git bisect good a3df8bbe0a704fa5c1609b9666b594f350558fe0
  # good: [fa608d2875b57fac792a9e1c11aa1da91737f04a] ACPI: PCI: Avoid misleading _OSC messages for non-PCIe host bridges without _OSC
  git bisect good fa608d2875b57fac792a9e1c11aa1da91737f04a
  # bad: [f234fdaae1cad8c39265e7ca0a14633076ec7154] ACPI: scan: Avoid registering platform devices with resource overlaps
  git bisect bad f234fdaae1cad8c39265e7ca0a14633076ec7154
  # first 'bad' commit: [f234fdaae1cad8c39265e7ca0a14633076ec7154] ACPI: scan: Avoid registering platform devices with resource overlaps

-- 
Cheers,
Nathan