CONFIG_EFI_CUSTOM_SSDT_OVERLAYS causes HDMI video capture device to fail [534d:2109] (no /dev/video{0,1})

[Ken Sharp]

Very recently my HDMI-->USB video capture device stopped working. /dev/video{0,1} is no longer created so it can no longer be accessed.

The device in question was bought from eBay:
http://web.archive.org/web/20200906083930/https://www.ebay.co.uk/p/15039374404?iid=313155173737
Photo attached, just in case.

linux-image-5.4.0-42-generic works.
linux-image-5.4.0-45-generic fails.
There appears to be no intermediate kernel releases.

$ lsusb
Bus 002 Device 003: ID 534d:2109

$ lsusb -t
/: Bus 02.Port 1: Dev 1, Class=root_hub, Driver=ehci-pci/2p, 480M
    |__ Port 1: Dev 2, If 0, Class=Hub, Driver=hub/8p, 480M
        |__ Port 2: Dev 3, If 0, Class=Video, Driver=snd-usb-audio, 480M
        |__ Port 2: Dev 3, If 1, Class=Video, Driver=snd-usb-audio, 480M
        |__ Port 2: Dev 3, If 2, Class=Audio, Driver=snd-usb-audio, 480M
        |__ Port 2: Dev 3, If 3, Class=Audio, Driver=snd-usb-audio, 480M
        |__ Port 2: Dev 3, If 4, Class=Human Interface Device, Driver=usbhid, 480M
        |__ Port 3: Dev 4, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M
        |__ Port 4: Dev 5, If 1, Class=Human Interface Device, Driver=usbhid, 1.5M
        |__ Port 4: Dev 5, If 0, Class=Human Interface Device, Driver=usbhid, 1.5M

Summary of kernels tested:

5.4.0-42 - OK
5.4.0-45 - Fails
5.4.0-47 - Fails
5.4.55 (CONFIG_EFI_CUSTOM_SSDT_OVERLAYS=n) - OK
5.9-rc5 - OK

As the upstream kernel works, this suggests there may be a bug in the Ubuntu kernel.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: linux-image-5.4.0-45-generic 5.4.0-45.49~18.04.2
ProcVersionSignature: Ubuntu 5.4.0-45.49~18.04.2-generic 5.4.55
Uname: Linux 5.4.0-45-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.20.9-0ubuntu7.17
Architecture: amd64
CurrentDesktop: MATE
Date: Sun Sep 6 09:36:32 2020
SourcePackage: linux-signed-hwe-5.4
UpgradeStatus: No upgrade log present (probably fresh install)

[Ken Sharp (kennybobs)]

$ diff /boot/config-5.4.0-4{2,5}-generic
(snip)
> CONFIG_EFI_CUSTOM_SSDT_OVERLAYS=y

My machine simply won't boot with acpi=off so I tried acpi_no_static_ssdt out of desperation. It made no difference.

Still an issue in -47.

[Ken Sharp (kennybobs)]

Recompiled -47 with CONFIG_EFI_CUSTOM_SSDT_OVERLAYS=n and the device works correctly as before.

I do not know if this is a kernel or firmware bug. Will try the upstream kernel to see if anything is different.

[Ken Sharp (kennybobs)]

Mainline kernel fails in the same way. Upstream latest works but is unusable for a number of reasons.

Summary:

5.4.0-42 - OK
5.4.0-45 - Fails
5.4.0-47 - Fails
5.4.55 (CONFIG_EFI_CUSTOM_SSDT_OVERLAYS=n) - OK
5.9-rc5 - OK

As the upstream kernel works, this suggests there may be a bug in the Ubuntu kernel.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Simon (b-simon-9)]

I have the same basic problem. Same USB device ID was working "not long ago", but now fails. One (perhaps very significant) difference. My system is Ubuntu 18.04, and the kernel seems to be a 4.15 variant. uname -a gives:

  Linux OptiPlex-9020 4.15.0-118-generic #119-Ubuntu SMP Tue Sep 8 12:30:01 UTC 2020 x86_64 x86_64 x86_64 GNU/Linux

Does this suggest it's a driver or similar supporting piece of code, rather than the kernel? Or perhaps it's a kernel patch that was included in older versions too?