vboxguest fails to build after debian unstable kernel update

[planck_length]

After updating to the latest kernel packages on Debian Unstable this morning, the vboxguest kernel module failed to build:

$ sudo dpkg-reconfigure linux-headers-3.2.0-4-amd64
Examining /etc/kernel/header_postinst.d.
run-parts: executing /etc/kernel/header_postinst.d/dkms 3.2.0-4-amd64
Error! Bad return status for module build on kernel: 3.2.0-4-amd64 (x86_64)
Consult /var/lib/dkms/vboxguest/4.2.10/build/make.log for more information.

Here's the relevant make.log file:

$ cat /var/lib/dkms/vboxguest/4.2.10/build/make.log
DKMS make.log for vboxguest-4.2.10 for kernel 3.2.0-4-amd64 (x86_64)
Sunday 24 March  07:37:39 EST 2013
make: Entering directory `/usr/src/linux-headers-3.2.0-4-amd64'
  LD      /var/lib/dkms/vboxguest/4.2.10/build/built-in.o
  LD      /var/lib/dkms/vboxguest/4.2.10/build/vboxguest/built-in.o
  CC [M]  /var/lib/dkms/vboxguest/4.2.10/build/vboxguest/VBoxGuest-linux.o
cc1: fatal error: /usr/src/linux-headers-3.2.0-4-common/include/linux/kconfig.h: No such file or directory
compilation terminated.
make[4]: *** [/var/lib/dkms/vboxguest/4.2.10/build/vboxguest/VBoxGuest-linux.o] Error 1
make[3]: *** [/var/lib/dkms/vboxguest/4.2.10/build/vboxguest] Error 2
make[2]: *** [_module_/var/lib/dkms/vboxguest/4.2.10/build] Error 2
make[1]: *** [sub-make] Error 2
make: *** [all] Error 2
make: Leaving directory `/usr/src/linux-headers-3.2.0-4-amd64'

[Frank Mehnert]

This is a problem with the Debian kernel because the Debian folks backported some feature from a more recent vanilla kernel to the maintenance version of the older kernel. We need a workaround.

[Frank Mehnert]

Fix is part of VBox 4.2.12. See r84603.