Hi Kirill,

Thank you for the patch! Perhaps something to improve:

[auto build test WARNING on next-20200729]
[also build test WARNING on v5.8]
[cannot apply to cgroup/for-next tip/timers/core net-next/master sparc-next/master net/master linus/master v5.8-rc7 v5.8-rc6 v5.8-rc5]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch]

url:    https://github.com/0day-ci/linux/commits/Kirill-Tkhai/proc-Introduce-proc-namespaces-directory-to-expose-namespaces-lineary/20200730-200346
base:    04b4571786305a76ad81757bbec78eb16a5de582
config: i386-randconfig-s001-20200805 (attached as .config)
compiler: gcc-9 (Debian 9.3.0-15) 9.3.0
reproduce:
        # apt-get install sparse
        # sparse version: v0.6.2-117-g8c7aee71-dirty
        # save the attached .config to linux build tree
        make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=i386 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>


sparse warnings: (new ones prefixed by >>)

>> fs/proc/namespaces.c:185:32: sparse: sparse: symbol 'namespaces_dentry_operations' was not declared. Should it be static?

Please review and possibly fold the followup patch.

---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org