Today, after changing the /etc/x11/xorg.conf file, after reboot, Configuring Kernel Parameters: and then hang the situation ...
Nothing, I have to change it back, restart, in the GRUB interface, press 'E', enter the grub editing mode, press E to the kernel, remove its RHGB parameters, and add Runlevel = 1 or 3, Enter, Press B to start, after startup, log in with root, change the original xorg.conf, and solve the problem.
In addition, some graphics cards such as NVIDA, if there is a RHGB parameter, there will be similar problems ...