Hi "Yordan, [FYI, it's a private test report for your RFC patch.] [auto build test WARNING on linux/master] [also build test WARNING on hnaz-mm/master linus/master v5.16-rc1 next-20211118] [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/Yordan-Karadzhov-VMware/namespac... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 8ab774587903771821b59471cc723bba6d893942 config: m68k-allyesconfig (attached as .config) compiler: m68k-linux-gcc (GCC) 11.2.0 reproduce (this is a W=1 build): wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # https://github.com/0day-ci/linux/commit/750c3589ff76d96017d8473ca8f0c6a03... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Yordan-Karadzhov-VMware/namespacefs-Proof-of-Concept/20211119-021813 git checkout 750c3589ff76d96017d8473ca8f0c6a03f3ef715 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): fs/namespacefs/inode.c:164:1: warning: no previous prototype for 'namespacefs_create_file' [-Wmissing-prototypes] 164 | namespacefs_create_file(const char *name, struct dentry *parent, | ^~~~~~~~~~~~~~~~~~~~~~~ fs/namespacefs/inode.c:173:1: warning: no previous prototype for 'namespacefs_create_dir' [-Wmissing-prototypes] 173 | namespacefs_create_dir(const char *name, struct dentry *parent, | ^~~~~~~~~~~~~~~~~~~~~~ fs/namespacefs/inode.c:184:6: warning: no previous prototype for 'namespacefs_remove_dir' [-Wmissing-prototypes] 184 | void namespacefs_remove_dir(struct dentry *dentry) | ^~~~~~~~~~~~~~~~~~~~~~ fs/namespacefs/inode.c:289:5: warning: no previous prototype for 'namespacefs_create_pid_ns_dir' [-Wmissing-prototypes] 289 | int namespacefs_create_pid_ns_dir(struct pid_namespace *ns) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ fs/namespacefs/inode.c:308:6: warning: no previous prototype for 'namespacefs_remove_pid_ns_dir' [-Wmissing-prototypes] 308 | void namespacefs_remove_pid_ns_dir(struct pid_namespace *ns) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 341 | int namespacefs_create_uts_ns_dir(struct uts_namespace *ns) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 360 | void namespacefs_remove_uts_ns_dir(struct uts_namespace *ns) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/namespacefs_create_uts_ns_dir +341 fs/namespacefs/inode.c 340 342 { 343 struct dentry *dentry; 344 int err; 345 346 err = create_inode_dir(&ns->ns, init_uts_ns.ns.dentry, ns->user_ns); 347 if (err) 348 return err; 349 350 dentry = namespacefs_create_file("uname", ns->ns.dentry, ns->user_ns, 351 &uts_fops, &ns->name); 352 if (IS_ERR(dentry)) { 353 dput(ns->ns.dentry); 354 return PTR_ERR(dentry); 355 } 356 357 return 0; 358 } 359 361 { 362 namespacefs_remove_dir(ns->ns.dentry); 363 } 364 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org