Comment # 96 on bug 1175599 from Takashi Iwai

(In reply to Luiz Cantarino from comment #95)
> Restart the machine, and send the kernel module to the blacklist:
> sudo echo blacklist = intel_vbtn >> /etc/modprobe.d/50-blacklist.conf &&
> mkinitrd && reboot

It's better to create a new file.  Also don't put '=' at the line.

  % su
  % echo blacklist intel_vbtn > /etc/modprobe.d/90-keyboard-workaround.conf
  % mkinitrd
  % reboot