Control: tags -1 + moreinfo upstream Hi Benoît,
On Thu, Dec 18, 2025 at 09:37:32PM +0100, Benoît Rouits wrote: > Package: src:linux > Version: 6.17.11-1 > Severity: normal > File: /usr/share/bug/linux-image-6.17.11+deb14-amd64/presubj > X-Debbugs-Cc: [email protected], [email protected] > User: [email protected] > Usertags: amd64 > > Dear Maintainer, > > I am experiencing a regression in linux image 6.17.11 (works with image > 6.17.9) > > * What led up to the situation? > > Trying to use the webcam with e.g. firefox (or qv4l2 for testing purpose) > > * What exactly did you do (or not do) that was effective (or > ineffective)? > > Went to a video chat site (medical in my case). > > * What was the outcome of this action? > > firefox did not ask permissions for integrated webcam video capture, and no > capture was possible. > > * What outcome did you expect instead? > > firefox to display a popup for accepting webcam capture, and use the webcam. > > > When using qv4l2, the capture is a black screen. > > various CLI checks: > > $ lsusb | grep -i uvc > Bus 002 Device 003: ID 13d3:5205 IMC Networks USB2.0 UVC 2M WebCam > > $ sudo dmesg | grep uvcvideo > [ 7.733171] usbcore: registered new interface driver uvcvideo > [ 1027.557731] uvcvideo 2-1.2:1.1: Failed to resubmit video URB (-1). > [ 1027.557798] uvcvideo 2-1.2:1.1: Failed to resubmit video URB (-1). > > $ v4l2-compliance | grep -5 "fail:" > > Control ioctls (Input 0): > test VIDIOC_QUERY_EXT_CTRL/QUERYMENU: OK > test VIDIOC_QUERYCTRL: OK > test VIDIOC_G/S_CTRL: OK > fail: v4l2-test-controls.cpp(980): ret != EINVAL (got 13) > test VIDIOC_G/S/TRY_EXT_CTRLS: FAIL > test VIDIOC_(UN)SUBSCRIBE_EVENT/DQEVENT: OK > test VIDIOC_G/S_JPEGCOMP: OK (Not Supported) > Standard Controls: 12 Private Controls: 0 > > If you need the same CLI output on the working linux image 6.17.9 for > comparison, or other CLI outputs, just ask me. First of all as we will upload soon the last version from the 6.17.y series, 6.17.13 and then move to 6.18.y there is no much point into analyzing if the issue is gone with 6.18.2. Thus, can you please test 6.18.2-1~exp1 as uploaded to experimental and check if the problem persist? If yes, and given you are able to reproduce the behaviour consistently, it would be great if you can bisect the problem between the two good and bad versions. Then we can report the problem upstream (and know it affects still 6.18.2). So that would involve compiling and testing a few kernels: git clone --single-branch -b linux-6.17.y https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable.git cd linux-stable git checkout v6.17.9 cp /boot/config-$(uname -r) .config yes '' | make localmodconfig make savedefconfig mv defconfig arch/x86/configs/my_defconfig # test 6.17.9 to ensure this is "good" make my_defconfig make -j $(nproc) bindeb-pkg ... install the resulting .deb package and confirm problem does not exist # test 6.17.11 to ensure this is "bad" git checkout v6.17.11 make my_defconfig make -j $(nproc) bindeb-pkg ... install the resulting .deb package and confirm problem exists With that confirmed, the bisection can start: git bisect start git bisect good v6.17.9 git bisect bad v6.17.11 In each bisection step git checks out a state between the oldest known-bad and the newest known-good commit. In each step test using: make my_defconfig make -j $(nproc) bindeb-pkg ... install, verify if problem exists and if the problem is hit run: git bisect bad and if the problem doesn't trigger run: git bisect good . Please pay attention to always select the just built kernel for booting, it won't always be the default kernel picked up by grub. Iterate until git announces to have identified the first bad commit. Then provide the output of git bisect log In the course of the bisection you might have to uninstall previous kernels again to not exhaust the disk space in /boot. Also in the end uninstall all self-built kernels again. Let us know on both first 6.18.2 (and then you can actually stop) or if it still present, if you can identify a breaking commit with the bisect procedure. Regards, Salvatore
