Hi Andrei,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.15-rc7 next-20180111]
[if your patch is applied to the wrong git tree, please drop us a note to help improve the system]

url:    https://github.com/0day-ci/linux/commits/Mike-Rapoport/vm-add-a-syscall-to-map-a-process-memory-into-a-pipe/20180111-220440
config: xtensa-allyesconfig (attached as .config)
compiler: xtensa-linux-gcc (GCC) 7.2.0
reproduce:
        wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
        chmod +x ~/bin/make.cross
        # save the attached .config to linux build tree
        make.cross ARCH=xtensa 

All warnings (new ones prefixed by >>):

quoted

<stdin>:1332:2: warning: #warning syscall process_vmsplice not implemented [-Wcpp]

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0-DAY kernel test infrastructure                Open Source Technology Center
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