It is not a bug in the graphics driver, but in the acpi backlight driver. It seems that Windows no longer uses the acpi backlight controller, and as a result all the firmware seems to be broken.
** Summary changed: - A potential fix for Intel HD 4000 graphics + [snb] more acpi backlight woes -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1189696 Title: [snb] more acpi backlight woes To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-video-intel/+bug/1189696/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp
