tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 4b358aabb93a2c654cd1dcab1a25a589f6e2b153 commit: 9cf1d7d830f4a586dfa4ddcaf9eae3959e0708ef [5325/7963] ARC: cmpxchg/xchg: rewrite as macros to make type safe config: arc-randconfig-s031-20210813 (attached as .config) compiler: arc-elf-gcc (GCC) 10.3.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.3-348-gf0e6938b-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commi... git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git git fetch --no-tags linux-next master git checkout 9cf1d7d830f4a586dfa4ddcaf9eae3959e0708ef # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-10.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=arc If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) fs/file.c:350:17: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file **old_fds @@ got struct file [noderef] __rcu **fd @@ fs/file.c:350:17: sparse: expected struct file **old_fds fs/file.c:350:17: sparse: got struct file [noderef] __rcu **fd fs/file.c:351:17: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file **new_fds @@ got struct file [noderef] __rcu **fd @@ fs/file.c:351:17: sparse: expected struct file **new_fds fs/file.c:351:17: sparse: got struct file [noderef] __rcu **fd fs/file.c:366:17: sparse: sparse: incompatible types in comparison expression (different address spaces): fs/file.c:366:17: sparse: struct file [noderef] __rcu * fs/file.c:366:17: sparse: struct file * fs/file.c:441:28: sparse: sparse: incorrect type in initializer (different address spaces) @@ expected struct fdtable [noderef] __rcu *fdt @@ got struct fdtable * @@ fs/file.c:608:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file *file @@ got struct file [noderef] __rcu * @@ fs/file.c:762:14: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file *file @@ got struct file [noderef] __rcu * @@ fs/file.c:813:30: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file *file @@ got struct file [noderef] __rcu * @@ fs/file.c:1038:16: sparse: sparse: incorrect type in assignment (different address spaces) @@ expected struct file *tofree @@ got struct file [noderef] __rcu * @@ vim +401 fs/file.c 02afc6267f6d55 Al Viro 2008-05-08 382 ce08b62d18b3f9 Oleg Nesterov 2014-01-11 383 static struct fdtable *close_files(struct files_struct * files) 7cf4dc3c8dbfdf Al Viro 2012-08-15 384 { 7cf4dc3c8dbfdf Al Viro 2012-08-15 385 /* 7cf4dc3c8dbfdf Al Viro 2012-08-15 386 * It is safe to dereference the fd table without RCU or 7cf4dc3c8dbfdf Al Viro 2012-08-15 387 * ->file_lock because this is the last reference to the ce08b62d18b3f9 Oleg Nesterov 2014-01-11 388 * files structure. 7cf4dc3c8dbfdf Al Viro 2012-08-15 389 */ ce08b62d18b3f9 Oleg Nesterov 2014-01-11 390 struct fdtable *fdt = rcu_dereference_raw(files->fdt); 9b80a184eaadc1 Alexey Dobriyan 2016-09-02 391 unsigned int i, j = 0; ce08b62d18b3f9 Oleg Nesterov 2014-01-11 392 7cf4dc3c8dbfdf Al Viro 2012-08-15 393 for (;;) { 7cf4dc3c8dbfdf Al Viro 2012-08-15 394 unsigned long set; 7cf4dc3c8dbfdf Al Viro 2012-08-15 395 i = j * BITS_PER_LONG; 7cf4dc3c8dbfdf Al Viro 2012-08-15 396 if (i >= fdt->max_fds) 7cf4dc3c8dbfdf Al Viro 2012-08-15 397 break; 7cf4dc3c8dbfdf Al Viro 2012-08-15 398 set = fdt->open_fds[j++]; 7cf4dc3c8dbfdf Al Viro 2012-08-15 399 while (set) { 7cf4dc3c8dbfdf Al Viro 2012-08-15 400 if (set & 1) { 7cf4dc3c8dbfdf Al Viro 2012-08-15 @401 struct file * file = xchg(&fdt->fd[i], NULL); 7cf4dc3c8dbfdf Al Viro 2012-08-15 402 if (file) { 7cf4dc3c8dbfdf Al Viro 2012-08-15 403 filp_close(file, files); 388a4c88064e7e Paul E. McKenney 2017-10-24 404 cond_resched(); 7cf4dc3c8dbfdf Al Viro 2012-08-15 405 } 7cf4dc3c8dbfdf Al Viro 2012-08-15 406 } 7cf4dc3c8dbfdf Al Viro 2012-08-15 407 i++; 7cf4dc3c8dbfdf Al Viro 2012-08-15 408 set >>= 1; 7cf4dc3c8dbfdf Al Viro 2012-08-15 409 } 7cf4dc3c8dbfdf Al Viro 2012-08-15 410 } ce08b62d18b3f9 Oleg Nesterov 2014-01-11 411 ce08b62d18b3f9 Oleg Nesterov 2014-01-11 412 return fdt; 7cf4dc3c8dbfdf Al Viro 2012-08-15 413 } 7cf4dc3c8dbfdf Al Viro 2012-08-15 414 :::::: The code at line 401 was first introduced by commit :::::: 7cf4dc3c8dbfdfde163d4636f621cf99a1f63bfb move files_struct-related bits from kernel/exit.c to fs/file.c :::::: TO: Al Viro <viro(a)zeniv.linux.org.uk&gt; :::::: CC: Al Viro <viro(a)zeniv.linux.org.uk&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org