** Description changed:

+ [SRU Justification]
+ 
+ Impact: The attempt to properly fix the warnings caused by the module in
+ 0.12.3-1ubuntu0.1 caused any other application than Chromium to no
+ longer detect available loopback devices. The tested capability was only
+ set in the capabilities set, but not in the device_caps set.
+ 
+ Fix: The patch was modified to change the IOCTL code as it was done in
+ v4l2loopback 0.12.5-1. This, probably contrary to what the kernel
+ developers tried to achieve, works around the restrictions by
+ additionally modifying the video device capabilities which the tests do
+ check against.
+ 
+ Testcase: Now tested with OBS v4l2sink connected (and exclusive_caps
+ set) against Chromium and Firefox. With 0.12.3-1ubuntu0.1 only Chromium
+ would find the loopback camera but with the proposed update both
+ Chromium and Firefox would work for me. And still no warnings.
+ 
+ Regression Potential: Essentially the difference to the released version
+ is that with exclusive_caps set, then device_caps of the video device
+ change. Which could throw off anything checking there and not expecting
+ any change. On the positive side, this is now exactly the behavior that
+ is exposed in 20.10/Groovy.
+ 
+ ---
+ 
  After the upgrade from 0.12.3-1 to 0.12.3-1ubuntu0.1 devices created using 
v4l2loopback are no longer available for use in applications (e.g. MS Teams and 
Zoom). With version 0.12.3-1 the devices would show up, e.g.
  modprobe v4l2loopback video nr=2 card label="test"
  would cause the new device to show up in those UIs as "test". With version 
0.12.3-1ubuntu0.1 device "test" is no longer shown.
  Downgrading to 0.12.3-1 fixes the problem.

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https://bugs.launchpad.net/bugs/1901491

Title:
  Created devices are not available

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