Hi Jinjiang, kernel test robot noticed the following build warnings: [auto build test WARNING on akpm-mm/mm-everything] url: https://github.com/intel-lab-lkp/linux/commits/Jinjiang-Tu/mm-ksm-fix-ksm-exec-support-for-prctl/20240322-141317 base: https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything patch link: https://lore.kernel.org/r/20240322060947.3254967-2-tujinjiang%40huawei.com patch subject: [PATCH v2 1/2] mm/ksm: fix ksm exec support for prctl config: s390-allnoconfig (https://download.01.org/0day-ci/archive/20240324/202403240716.8B7CiDbr-lkp@xxxxxxxxx/config) compiler: clang version 19.0.0git (https://github.com/llvm/llvm-project 23de3862dce582ce91c1aa914467d982cb1a73b4) reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240324/202403240716.8B7CiDbr-lkp@xxxxxxxxx/reproduce) If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202403240716.8B7CiDbr-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from fs/exec.c:30: In file included from include/linux/mm.h:2211: include/linux/vmstat.h:514:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion] 514 | return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_" | ~~~~~~~~~~~ ^ ~~~ >> fs/exec.c:275:6: warning: variable 'err' is used uninitialized whenever 'if' condition is true [-Wsometimes-uninitialized] 275 | if (ksm_execve(mm)) | ^~~~~~~~~~~~~~ fs/exec.c:305:9: note: uninitialized use occurs here 305 | return err; | ^~~ fs/exec.c:275:2: note: remove the 'if' if its condition is always false 275 | if (ksm_execve(mm)) | ^~~~~~~~~~~~~~~~~~~ 276 | goto err_ksm; | ~~~~~~~~~~~~ fs/exec.c:257:9: note: initialize the variable 'err' to silence this warning 257 | int err; | ^ | = 0 2 warnings generated. vim +275 fs/exec.c 254 255 static int __bprm_mm_init(struct linux_binprm *bprm) 256 { 257 int err; 258 struct vm_area_struct *vma = NULL; 259 struct mm_struct *mm = bprm->mm; 260 261 bprm->vma = vma = vm_area_alloc(mm); 262 if (!vma) 263 return -ENOMEM; 264 vma_set_anonymous(vma); 265 266 if (mmap_write_lock_killable(mm)) { 267 err = -EINTR; 268 goto err_free; 269 } 270 271 /* 272 * Need to be called with mmap write lock 273 * held, to avoid race with ksmd. 274 */ > 275 if (ksm_execve(mm)) 276 goto err_ksm; 277 278 /* 279 * Place the stack at the largest stack address the architecture 280 * supports. Later, we'll move this to an appropriate place. We don't 281 * use STACK_TOP because that can depend on attributes which aren't 282 * configured yet. 283 */ 284 BUILD_BUG_ON(VM_STACK_FLAGS & VM_STACK_INCOMPLETE_SETUP); 285 vma->vm_end = STACK_TOP_MAX; 286 vma->vm_start = vma->vm_end - PAGE_SIZE; 287 vm_flags_init(vma, VM_SOFTDIRTY | VM_STACK_FLAGS | VM_STACK_INCOMPLETE_SETUP); 288 vma->vm_page_prot = vm_get_page_prot(vma->vm_flags); 289 290 err = insert_vm_struct(mm, vma); 291 if (err) 292 goto err; 293 294 mm->stack_vm = mm->total_vm = 1; 295 mmap_write_unlock(mm); 296 bprm->p = vma->vm_end - sizeof(void *); 297 return 0; 298 err: 299 ksm_exit(mm); 300 err_ksm: 301 mmap_write_unlock(mm); 302 err_free: 303 bprm->vma = NULL; 304 vm_area_free(vma); 305 return err; 306 } 307 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki
