[Wily] nvidia-libopencl1-* not installable

[Thomas Karl Pietrowski]

I just noticed that installing the OpenCL doesn't work. When trying to install any of these packages APT wants to remove all packages related to ocl-icd-libopencl1. Well, while looking at the nvidia packages I noticed that all nvidia-libopencl1-* packages want to replace and provide libopencl1, but this might be the old name of the generic library.
Currently it is called ocl-icd-libopencl1, so correcting this should be very easy!

ProblemType: Bug
DistroRelease: Ubuntu 15.10
Package: nvidia-libopencl1-352 (not installed)
ProcVersionSignature: Ubuntu 4.2.0-11.13-generic 4.2.1
Uname: Linux 4.2.0-11-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 2.19-0ubuntu1
Architecture: amd64
CurrentDesktop: KDE
Date: Sat Sep 26 12:23:03 2015
SourcePackage: nvidia-graphics-drivers-352
UpgradeStatus: No upgrade log present (probably fresh install)

[Graham Inggs (ginggs)]

> while looking at the nvidia packages I noticed that all
> nvidia-libopencl1-* packages want to replace and provide libopencl1,

That is correct, you can only have one libopencl1 (OpenCL ICD Loader) package installed.
In most circumstances you would have ocl-icd-libopencl1, but if you manually installed nvidia-libopencl1-352, it should remove any other OpenCL ICD Loader.

You can however, have multiple OpenCL ICDs installed, and nvidia-opencl-icd-352 is one of these.

Please tell me what OpenCL packages you had installed, what you were trying to install, and what apt wanted to remove.

[Thomas Karl Pietrowski (thopiekar)]

So far there are not much applications and libraries using opencl, but I fall into this when just trying to install clinfo (Just a simple testing application like vainfo or vdpauinfo) with nvidia-libopencl1-*.

As you can see it also affects wine1.6.

thopiekar@home:~$ LANG=C sudo apt-get install nvidia-libopencl1-352
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following packages were automatically installed and are no longer required:
  libcublas6.5 libcudart6.5 libcufft6.5 libcufftw6.5 libcuinj64-6.5 libcurand6.5 libcusparse6.5 libnppc6.5 libnppi6.5 libnpps6.5 libnvblas6.5 libnvtoolsext1 libnvvm2 libthrust-dev
  libvdpau-dev nvidia-cuda-dev nvidia-cuda-doc nvidia-cuda-gdb nvidia-profiler nvidia-visual-profiler opencl-headers
Use 'apt-get autoremove' to remove them.
The following packages will be REMOVED:
  clinfo libhwloc-plugins nvidia-cuda-toolkit nvidia-opencl-dev ocl-icd-libopencl1 ocl-icd-libopencl1:i386 wine1.6 wine1.6-amd64 wine1.6-i386:i386
The following NEW packages will be installed:
  nvidia-libopencl1-352
0 upgraded, 1 newly installed, 9 to remove and 5 not upgraded.
Need to get 18,9 kB of archives.
After this operation, 296 MB disk space will be freed.
Do you want to continue? [Y/n] n
Abort.

[Thomas Karl Pietrowski (thopiekar)]

Btw. this problem might also be present in Vivid, I guess.

[Graham Inggs (ginggs)]

> thopiekar@home:~$ LANG=C sudo apt-get install nvidia-libopencl1-352

There is your problem. Everything in the archive that uses OpenCL was compiled against ocl-icd-libopencl1, so you need that.
You shouldn't ever need to install nvidia-libopencl1-352.

The ocl-icd-libopencl1 OpenCL ICD Loader is capable of loading nvidia-opencl-icd-352 (and any other OpenCL ICD in the archive).

[Thomas Karl Pietrowski (thopiekar)]

So, why does clinfo say that there are no devices?
If you are right I would expect there some output about my GPU.

Is ocl-icd-libopencl1 not properly finding the ICD?

[Graham Inggs (ginggs)]

> So, why does clinfo say that there are no devices?

Try:
$ sudo apt-get install nvidia-modprobe
$ clinfo

[Thomas Karl Pietrowski (thopiekar)]

Works! So, wouldn't it be a good idea making nvidia-opencl-icd-* at least recommend to install nvidia-modprobe? Other people won't get confused like me trying to install the nvidia-libopencl1-*, too.

thopiekar@home:~$ clinfo
Number of platforms 1
  Platform Name NVIDIA CUDA
  Platform Vendor NVIDIA Corporation
  Platform Version OpenCL 1.2 CUDA 7.5.18
  Platform Profile FULL_PROFILE
  Platform Extensions cl_khr_byte_addressable_store cl_khr_icd cl_khr_gl_sharing cl_nv_compiler_options cl_nv_device_attribute_query cl_nv_pragma_unroll cl_nv_copy_opts
  Platform Extensions function suffix NV

  Platform Name NVIDIA CUDA
Number of devices 1
  Device Name GeForce GT 720
  Device Vendor NVIDIA Corporation
  Device Vendor ID 0x10de
  Device Version OpenCL 1.2 CUDA
  Driver Version 352.41
  Device OpenCL C Version OpenCL C 1.2
  Device Type GPU
  Device Profile FULL_PROFILE
  Device Topology (NV) PCI-E, 02:00.0
  Max compute units 1
  Max clock frequency 797MHz
  Compute Capability (NV) 3.5
  Device Partition (core)
    Max number of sub-devices 1
    Supported partition types None
  Max work item dimensions 3
  Max work item sizes 1024x1024x64
  Max work group size 1024
  Preferred work group size multiple 32
  Warp size (NV) 32
  Preferred / native vector sizes
    char 1 / 1
    short 1 / 1
    int 1 / 1
    long 1 / 1
    half 0 / 0 (n/a)
    float 1 / 1
    double 1 / 1 (cl_khr_fp64)
  Half-precision Floating-point support (n/a)
  Single-precision Floating-point support (core)
    Denormals Yes ...

[Graham Inggs (ginggs)]

> Works!

Glad to hear it!

> So, wouldn't it be a good idea making nvidia-opencl-icd-* at least
> recommend to install nvidia-modprobe? Other people won't get
> confused like me trying to install the nvidia-libopencl1-*, too.

We would like to have nvidia-graphics-drivers-* recommend nvidia-modprobe, or provide some way of automatically loading the kernel modules and creating the device nodes. The nvidia-modprobe package is currently in 'universe' and would need to be included in 'main' before a package in 'restricted' can depend on or recommend it.

I'm going to mark this as a duplicate of the bug where we are tracking that.