ACPI Warning Argument #4 type mismatch

Question

Output of dmesg: http://paste.ubuntu.com/23381803/ In the dmesg, there is the below error:

ACPI Warning: \_SB_.PCI0.RP01.PXSX._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] (20150930/nsarguments-95)

which seems like BIOS or something related error.

How do I fix this? Is there any case to be related to this bug? https://bugs.launchpad.net/ubuntu/+source/linux/+bug/15884 (I had filed this bug and am just using a new OS on the same machine.

Other details:

 ~  lsb_release -a
No LSB modules are available.
Distributor ID: neon
Description:    KDE neon User Edition 5.8
Release:        16.04
Codename:       xenial
 ~  uname -a
Linux neon 4.4.0-45-generic #66-Ubuntu SMP Wed Oct 19 14:12:37 UTC 2016 x86_64 x86_64 x86_64 GNU/Linux

Solution

The ACPI Warning: ...._DSM: Argument #4 type mismatch - Found [Buffer], ACPI requires [Package] warning could be annoying but is harmless. The message is shown because Nvidia does not conform to the official ACPI specification.

It can also not be "fixed" by using the required "Package" type because it would break many laptops with Nvidia GPUs, resulting in higher power consumption. For a more technical description, see this discussion.

As a user, the best thing you can do is ignoring it. It will only occur when the GPU driver (nvidia, nouveau, bbswitch) is loaded, or when a GPU in a hybrid graphics laptop is powered off.

Comments

[WinEunuuchs2Unix]

I ignore the ACPI warnings unless brightness keys don't work, sound keys don't work, etc.

[stephanmg]

Thanks for providing this answer! @OP: Please accept this answer.