Linux Kernel Module Cheat

On ARM, startx hangs at a message:

vgaarb: this pci device is not a vga device

and nothing shows on the screen, and:

grep EE /var/log/Xorg.0.log

says:

(EE) Failed to load module "modesetting" (module does not exist, 0)

A friend told me this but I haven’t tried it yet:

xf86-video-modesetting is likely the missing ingredient, but it does not seem possible to activate it from Buildroot currently without patching things.
xf86-video-fbdev should work as well, but we need to make sure fbdev is enabled, and maybe add some line to the Xorg.conf