Hi Christian,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on linus/master]
[also build test WARNING on v4.20-rc3]
[cannot apply to next-20181119]
[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/Christian-Brauner/proc-allow-signaling-processes-via-file-descriptors/20181120-063836
config: riscv-tinyconfig (attached as .config)
compiler: riscv64-linux-gcc (GCC) 8.1.0
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
        GCC_VERSION=8.1.0 make.cross ARCH=riscv 

All warnings (new ones prefixed by >>):

>> <stdin>:1338:2: warning: #warning syscall procfd_signal not implemented [-Wcpp]

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0-DAY kernel test infrastructure                Open Source Technology Center
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