Confirming this affects Ubuntu 24.04 (Noble) with the HWE 7.0 kernel
(7.0.0-28-generic).

A community-suggested patch was posted upstream
(https://github.com/v4l2loopback/v4l2loopback/issues/669#issuecomment-5011058299)
that fixes the v4l2_fh_add/v4l2_fh_del signature change and lets
v4l2loopback 0.12.7 compile and load successfully on kernel 7.0. I can
confirm this patch works for the build step.

However, applying it surfaced a separate, more serious runtime issue:
actually streaming through the resulting device causes a full system
hard-freeze (unresponsive display, no SysRq/REISUB response, requiring a
hard power cycle). This does not occur on kernel 6.17 with the same
userspace pipeline. Filed separately upstream as
https://github.com/v4l2loopback/v4l2loopback/issues/670, since it's a
distinct bug from the build failure this ticket tracks.

Given the age gap between Ubuntu's packaged 0.12.7 and current upstream
(0.15.4 -- 9 releases behind), it might be worth considering an update
of the packaged version rather than a minimal compile-fix patch, since
the runtime issue may already be resolved upstream in later releases
(unconfirmed on my end so far).

---
Filed with the help of Claude (Anthropic).

** Bug watch added: github.com/v4l2loopback/v4l2loopback/issues #669
   https://github.com/v4l2loopback/v4l2loopback/issues/669

** Bug watch added: github.com/v4l2loopback/v4l2loopback/issues #670
   https://github.com/v4l2loopback/v4l2loopback/issues/670

-- 
You received this bug notification because you are a member of Ubuntu
Bugs, which is subscribed to Ubuntu.
https://bugs.launchpad.net/bugs/2161037

Title:
  v4l2loopback fails to build on kernel 7.0 HWE

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/v4l2loopback/+bug/2161037/+subscriptions


-- 
ubuntu-bugs mailing list
[email protected]
https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs

Reply via email to