i tried to install the mesa driver for amd gpu,and the next time i booted the system,i encountered this:failed to load or save backlight amdgpu_b10,and i can not access to the system now.i have searched the same problem but it seems no one have had the same problem yet.
The system have by default the driver for amd graphics cards. What driver did you install? Did you try to uninstall it? Did you try to boot up with the fallback option, advance options in grub. Did you try to change to a tty with ctrl+alt+f3 when the boot up stuck?
Disable the service as mentioned here