Comment 6 for bug 1353214

(synaptic:19848): GLib-CRITICAL **: g_child_watch_add_full: assertion 'pid > 0' failed
(Reading database ... 358139 files and directories currently installed.)
Removing libcuda1-331-updates (331.38-0ubuntu7.1) ...
Removing nvidia-331-updates (331.38-0ubuntu7.1) ...
Removing all DKMS Modules
Done.
update-alternatives: using /usr/lib/nvidia-331-updates-prime/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in auto mode
update-alternatives: using /usr/lib/nvidia-331-updates-prime/alt_ld.so.conf to provide /etc/ld.so.conf.d/x86_64-linux-gnu_GL.conf (x86_64-linux-gnu_gl_conf) in auto mode
update-alternatives: using /usr/lib/i386-linux-gnu/mesa/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in auto mode
INFO:Disable nvidia-331-updates
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/dell_latitude
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/put_your_quirks_here
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/lenovo_thinkpad
stop: Unknown instance:
update-initramfs: deferring update (trigger activated)
dpkg: nvidia-libopencl1-331-updates: dependency problems, but removing anyway as you requested:
 nvidia-opencl-icd-331-updates depends on ocl-icd-libopencl1 | nvidia-libopencl1-331-updates; however:
  Package ocl-icd-libopencl1 is not installed.
  Package nvidia-libopencl1-331-updates is to be removed.

Removing nvidia-libopencl1-331-updates (331.38-0ubuntu7.1) ...
Processing triggers for libc-bin (2.19-0ubuntu6.1) ...
Processing triggers for man-db (2.6.7.1-1) ...
Processing triggers for initramfs-tools (0.103ubuntu4.2) ...
update-initramfs: Generating /boot/initrd.img-3.13.0-34-generic
Selecting previously unselected package ocl-icd-libopencl1:i386.
(Reading database ... 357941 files and directories currently installed.)
Preparing to unpack .../ocl-icd-libopencl1_2.1.3-4_i386.deb ...
Unpacking ocl-icd-libopencl1:i386 (2.1.3-4) ...
Selecting previously unselected package libcuda1-331.
Preparing to unpack .../libcuda1-331_331.38-0ubuntu7.1_i386.deb ...
Unpacking libcuda1-331 (331.38-0ubuntu7.1) ...
Selecting previously unselected package nvidia-331.
Preparing to unpack .../nvidia-331_331.38-0ubuntu7.1_i386.deb ...
Unpacking nvidia-331 (331.38-0ubuntu7.1) ...
Selecting previously unselected package nvidia-opencl-icd-331.
Preparing to unpack .../nvidia-opencl-icd-331_331.38-0ubuntu7.1_i386.deb ...
Unpacking nvidia-opencl-icd-331 (331.38-0ubuntu7.1) ...
dpkg: error processing archive /var/cache/apt/archives/nvidia-opencl-icd-331_331.38-0ubuntu7.1_i386.deb (--unpack):
 trying to overwrite '/usr/lib/i386-linux-gnu/libnvidia-opencl.so.331.38', which is also in package nvidia-opencl-icd-331-updates 331.38-0ubuntu7.1
dpkg-deb: error: subprocess paste was killed by signal (Broken pipe)
Processing triggers for doc-base (0.10.5) ...
Processing 1 added doc-base file...
Registering documents with scrollkeeper...
Processing triggers for man-db (2.6.7.1-1) ...
Processing triggers for ureadahead (0.100.0-16) ...
Errors were encountered while processing:
 /var/cache/apt/archives/nvidia-opencl-icd-331_331.38-0ubuntu7.1_i386.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)
A package failed to install. Trying to recover:
Setting up nvidia-331 (331.38-0ubuntu7.1) ...
update-alternatives: using /usr/lib/nvidia-331/ld.so.conf to provide /etc/ld.so.conf.d/i386-linux-gnu_GL.conf (i386-linux-gnu_gl_conf) in auto mode
update-alternatives: warning: skip creation of /usr/lib32/vdpau/libvdpau_nvidia.so.1 because associated file /usr/lib32/nvidia-331/vdpau/libvdpau_nvidia.so.1 (of link group i386-linux-gnu_gl_conf) doesn't exist
update-alternatives: warning: skip creation of /usr/lib32/libvdpau_nvidia.so because associated file /usr/lib32/nvidia-331/vdpau/libvdpau_nvidia.so (of link group i386-linux-gnu_gl_conf) doesn't exist
update-alternatives: using /usr/lib/nvidia-331/alt_ld.so.conf to provide /etc/ld.so.conf.d/x86_64-linux-gnu_GL.conf (x86_64-linux-gnu_gl_conf) in auto mode
update-alternatives: using /usr/share/nvidia-331/glamor.conf to provide /usr/share/X11/xorg.conf.d/glamoregl.conf (glamor_conf) in auto mode
update-initramfs: deferring update (trigger activated)
INFO:Enable nvidia-331
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/dell_latitude
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/put_your_quirks_here
DEBUG:Parsing /usr/share/ubuntu-drivers-common/quirks/lenovo_thinkpad
Adding system user `nvidia-persistenced' (UID 126) ...
Adding new group `nvidia-persistenced' (GID 135) ...
Adding new user `nvidia-persistenced' (UID 126) with group `nvidia-persistenced' ...
Not creating home directory `/'.
Loading new nvidia-331-331.38 DKMS files...
First Installation: checking all kernels...
Building only for 3.13.0-34-generic
Building for architecture i686
Building initial module for 3.13.0-34-generic
Done.

nvidia_331:
Running module version sanity check.
 - Original module
   - No original module exists within this kernel
 - Installation
   - Installing to /lib/modules/3.13.0-34-generic/updates/dkms/

depmod....

DKMS: install completed.
Setting up ocl-icd-libopencl1:i386 (2.1.3-4) ...
Setting up libcuda1-331 (331.38-0ubuntu7.1) ...
Processing triggers for initramfs-tools (0.103ubuntu4.2) ...
update-initramfs: Generating /boot/initrd.img-3.13.0-34-generic
Processing triggers for libc-bin (2.19-0ubuntu6.1) ...

Hope this may help.