Hi Guennadi, On 11/04/18 10:56, Guennadi Liakhovetski wrote: > Hi Laurent, > > Not sure whether that's a kernel or a user-space problem, but UVC related > anyway. I've got a UVC 1.5 (!) Logitech camera, that used to work fine > with earlier kernels. I now installed "media 4.16" and saw, that the > kernel log was filling with messages like > > uvcvideo: Failed to query (GET_MIN) UVC control 2 on unit 1: -32 (exp. 1). > > The expected /dev/video[01] nodes were not created correctly, and the > hard-drive was getting full very quickly. The latter was happening because > the the /var/log/uvcdynctrl-udev.log file was growing. A truncated sample > is attached. At its bottom you see messages > > [libwebcam] Warning: The driver behind device video0 has a slightly buggy implementation > of the V4L2_CTRL_FLAG_NEXT_CTRL flag. It does not return the next higher > control ID if a control query fails. A workaround has been enabled. > > repeating, which continues even if the camera is unplugged. The kernel is > the head of the master branch of git://linuxtv.org/media_tree.git > > Just figured out this commit > > From: Edgar Thier <info@xxxxxxxxxxxxxx> > Date: Thu, 12 Oct 2017 03:54:17 -0400 > Subject: [PATCH] media: uvcvideo: Apply flags from device to actual properties > > as the culprit. Without it everything is back to normal. I've already investigated and fixed this: Please apply: https://patchwork.kernel.org/patch/10299735/ You stated that this is showing up on a v4.16 kernel ... but as far as I'm aware - this feature shouldn't make it in until v4.17. Are you using linux-next or a media/master or such ? Regards Kieran > Thanks > Guennadi >
