OpenCL installation on Linux

[itanon]

Actually, if you know what the problem of the  K a l i  packages are and how one normally needs to install the drivers/ICDs, then it is quite easy to start hashcat also with The-Distribution-Which-Does-Not-Handle-OpenCL-Well (K a l i):
(as said I tested it, because we got several reports of users that failed to get it to work)

Code:

# sha1sum k a l i-linux-2016.2-amd64.iso
25cc6d53a8bd8886fcb468eb4fbb4cdfac895c65  k a l i-linux-2016.2-amd64.iso
# # start the "Graphical installation" with CD, after that:
# hashcat -b
# # got the "clBuildProgram(): CL_BUILD_PROGRAM_FAILURE" error, only Mesa seems
# # to be loaded
# apt-get update
# apt-get dist-upgrade
# apt-get autoremove
# reboot

# hashcat -b
# # still not working

# # make sure that kernel 4.9.0-k a l i 2-amd64 is loaded because we need the kernel
# # headers!
# # (4.6.0-k a l i1-amd64 (default) is not working)
# # make sure kernel 4.9.0-k a l i 2-amd64 is installed
# # update-grub and make sure that the "correct" kernel is selected with grub!
# # (this is not guaranteed unfortunately)
# reboot

# # after several tries finally the "correct"??? kernel was loaded
# # (uname -r saying "4.9.0-k a l i 2-amd64")

# apt-get install nvidia-driver     # this seems to correctly/automatically
# # install the kernel headers, but it only compiles the modules if the
# # "correct kernel" is running
# apt-get install nvidia-opencl-icd
# reboot # such that the nvidia modules load correctly

# hashcat -b
# # after reboot, I saw hashcat working for the first time! Hurray!
# # (but this was very tedious and time consuming)

My  k a l i kernel's version is 4.6.... You're telling me this is the problem.... I didn't know that version wasn't supported....So I'd better update the K a l i kernel to 4.9...Right?
P.s. why the term "k a l i" is overwritten by the forum??

[itanon]

From the official k a l i driver support page (http://docs.k a l i.org/general-use/install-nvidia-drivers-on-k a l i-linux) I've found a few more things that could be useful in our troubleshooting... 

First of all, in that page, the gpu driver is then checked running hashcat's benchmark, so this is just our case(get hashcat works).
The SW packages that(according to the guide) are installed in order to get gpu works(with hashcat)are:
open ICD driver
Nvidia driver
Cuda toolkit
It's recommended to disable nouveau driver too(the native nvidia open driver in Linux distros) but with the lasts proprietary Nvidia drivers release(during installation)the nouveau is automatically blacklisted and disabled so no worry about that.

Coming to our situation, till now i've tried to run hashcat only with driver and openCL installed and the things went always bad(hashcat doesn't works).
So I'm wondering: how about install prop Nvidia driver+icd without openCL(like the guide said)? 
In fact, at the moment, the openCL is the one who results more problem causing, since it is not supported by k a l i (at least from the version 2016.2 kernel 4.6 that I'm running)and I think this(unsupported openCL) prevents hashcat to work properly.

At the end of the story: if that guide is written correctly, hashcat should properly works only by installing proprietary Nvidia driver+icd+toolkit(this last could be avoided I think).

That's all the infos I got about hashcat+gpu driver installation.
Not tested yet.
Please feel free to share your opinion and correct me in case something is wrong