dkms uses wrong gcc version

[Pavel Boldin]

DKMS seems to use default (/usr/bin/gcc) GCC binary to build kernel modules, without checking either it pointing to version of gcc used to build kernel or not.

This can be problem when one uses update-alternatives to change default GCC path to another GCC version. This causes modules to be built with wrong gcc version, possibly crashing them and kernel itself (it was a case with bbswitch module on my system).

Not only DKMS uses wrong GCC version, system also allowed to insert modules compiled with wrong version of gcc.

davinchi@nirvana:~$ lsb_release -rd
Description: Ubuntu 12.04 LTS
Release: 12.04
# actually I updated from 11.10 to 12.04
davinchi@nirvana:~$ sudo apt-cache policy dkms
dkms:
  Installed: 2.2.0.3-1ubuntu3
  Candidate: 2.2.0.3-1ubuntu3
  Version table:
 *** 2.2.0.3-1ubuntu3 0
        500 http://ru.archive.ubuntu.com/ubuntu/ precise/main amd64 Packages
        100 /var/lib/dpkg/status

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.