Reinstalling the nvidia-331 package appears to have solved it. Still not sure what caused the first build to fail, though.
-- You received this bug notification because you are a member of Desktop Packages, which is subscribed to nvidia-graphics-drivers-331 in Ubuntu. https://bugs.launchpad.net/bugs/1325426 Title: nvidia-331 331.38-0ubuntu7: nvidia-331 kernel module failed to build Status in “nvidia-graphics-drivers-331” package in Ubuntu: New Bug description: driver failed to build when installing linux-image-3.13.0-29-generic (3.13.0-29.52) and friends from the trusty-proposed source ERROR: Kernel configuration is invalid."; \ echo >&2 " include/generated/autoconf.h or include/config/auto.conf are missing.";\ I'll attach the build log in case apport didn't do it automatically. ProblemType: Package DistroRelease: Ubuntu 14.04 Package: nvidia-331 331.38-0ubuntu7 ProcVersionSignature: Ubuntu 3.13.0-27.50-generic 3.13.11 Uname: Linux 3.13.0-27-generic x86_64 ApportVersion: 2.14.1-0ubuntu3.2 Architecture: amd64 DKMSKernelVersion: 3.13.0-29-generic Date: Sun Jun 1 16:46:37 2014 PackageVersion: 331.38-0ubuntu7 SourcePackage: nvidia-graphics-drivers-331 Title: nvidia-331 331.38-0ubuntu7: nvidia-331 kernel module failed to build UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/nvidia-graphics-drivers-331/+bug/1325426/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : desktop-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp