make: Warning: File `Makefile' has modification time 1.7e+04 s in the future
make -C /lib/modules/4.4.0-142-generic/build M=/home/user/kernrk modules
make[1]: Entering directory `/usr/src/linux-headers-4.4.0-142-generic'
./scripts/Makefile.build:290: target `/home/user/kernrk/kernrk.c' doesn't match the target pattern
make[2]: Warning: File `/home/user/kernrk/Makefile' has modification time 1.7e+04 s in the future
make[2]: warning:  Clock skew detected.  Your build may be incomplete.
  Building modules, stage 2.
make[2]: Warning: File `/home/user/kernrk/Makefile' has modification time 1.7e+04 s in the future
  MODPOST 0 modules
make[2]: warning:  Clock skew detected.  Your build may be incomplete.
make[1]: Leaving directory `/usr/src/linux-headers-4.4.0-142-generic'
make: warning:  Clock skew detected.  Your build may be incomplete.