/usr/share/darktable/kernels/ is in darktable 2.0.3-1.
This file is owned by root:root, with mode 0o755.
..
/usr/share/darktable/kernels/atrous.cl
/usr/share/darktable/kernels/basic.cl
/usr/share/darktable/kernels/bilateral.cl
/usr/share/darktable/kernels/blendop.cl
/usr/share/darktable/kernels/bloom.cl
/usr/share/darktable/kernels/colorreconstruction.cl
/usr/share/darktable/kernels/colorspace.cl
/usr/share/darktable/kernels/common.h
/usr/share/darktable/kernels/demosaic_other.cl
/usr/share/darktable/kernels/demosaic_ppg.cl
/usr/share/darktable/kernels/denoiseprofile.cl
/usr/share/darktable/kernels/extended.cl
/usr/share/darktable/kernels/gaussian.cl
/usr/share/darktable/kernels/highpass.cl
/usr/share/darktable/kernels/nlmeans.cl
/usr/share/darktable/kernels/programs.conf
/usr/share/darktable/kernels/sharpen.cl
/usr/share/darktable/kernels/soften.cl