Package: linux-image-4.9.0-9-amd64 Version: 4.9.168-1
After updating the kernel from linux-image-4.9.0-8-amd64 to linux-image-4.9.0-9-amd64, the screen backlight on the Asus EeePC 1215b laptop stops working. I tried to install Debian 9.8 and perform an apt-get upgrade, it did not cause any problems. But then I tried apt-get dist-upgrade and the backlight stopped working. Now, if I load the old kernel, the backlight works correctly again. But with the new kernel it does not work. From here I conclude that the problem is in the kernel, but I am not sure (how can I check this?). When I try to change the backlight brightness using the keyboard, I see that the indicator in XFCE shows changes, but the backlight still does not turn on. I tried the clean install Debian 9.9, there the backlight didn't work initially (but in the installer it worked). I also encountered a similar problem in LMDE 3 "Cindy".