Hi "Eric, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on bpf/master] [also build test WARNING on linus/master v5.9-rc1 next-20200817] [cannot apply to bpf-next/master linux/master] [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/Eric-W-Biederman/exec-Move-unsha... base: https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf.git master config: i386-randconfig-m021-20200818 (attached as .config) compiler: gcc-9 (Debian 9.3.0-15) 9.3.0 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; smatch warnings: kernel/bpf/task_iter.c:162 task_file_seq_get_next() warn: ignoring unreachable code. # https://github.com/0day-ci/linux/commit/66f80aa453b17f8932b42e18265dba5fd... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Eric-W-Biederman/exec-Move-unshare_files-to-fix-posix-file-locking-during-exec/20200818-061552 git checkout 66f80aa453b17f8932b42e18265dba5fdb32490e vim +162 kernel/bpf/task_iter.c 128 129 static struct file * 130 task_file_seq_get_next(struct bpf_iter_seq_task_file_info *info, 131 struct task_struct **task) 132 { 133 struct pid_namespace *ns = info->common.ns; 134 u32 curr_tid = info->tid; 135 struct task_struct *curr_task; 136 unsigned int curr_fd = info->fd; 137 138 /* If this function returns a non-NULL file object, 139 * it held a reference to the task/file. 140 * Otherwise, it does not hold any reference. 141 */ 142 again: 143 if (*task) { 144 curr_task = *task; 145 curr_fd = info->fd; 146 } else { 147 curr_task = task_seq_get_next(ns, &curr_tid); 148 if (!curr_task) 149 return NULL; 150 151 /* set *task and info->tid */ 152 *task = curr_task; 153 if (curr_tid == info->tid) { 154 curr_fd = info->fd; 155 } else { 156 info->tid = curr_tid; 157 curr_fd = 0; 158 } 159 } 160 161 rcu_read_lock(); 163 struct file *f; 164 165 f = fnext_task(curr_task, &curr_fd); 166 if (!f) 167 break; 168 169 /* set info->fd */ 170 info->fd = curr_fd; 171 get_file(f); 172 rcu_read_unlock(); 173 return f; 174 } 175 176 /* the current task is done, go to the next task */ 177 rcu_read_unlock(); 178 put_task_struct(curr_task); 179 *task = NULL; 180 info->fd = 0; 181 curr_tid = ++(info->tid); 182 goto again; 183 } 184 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org