tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master head: 44a2f39e611ac0bc1f17c288a583d7f2e5684aa7 commit: b0bb08b2d5f399369a906eff0287e64b531881d8 [7459/8237] mm/shmem: turn shmem_alloc_page() into shmem_alloc_folio() config: x86_64-randconfig-a001 (https://download.01.org/0day-ci/archive/20220504/202205040121.S0ILU2a8-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project 363b3a645a1e30011cc8da624f13dac5fd915628) 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://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=b0bb08b2d5f399369a906eff0287e64b531881d8 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 b0bb08b2d5f399369a906eff0287e64b531881d8 # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=x86_64 SHELL=/bin/bash If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): >> mm/shmem.c:2354:8: warning: variable 'page' is uninitialized when used here [-Wuninitialized] if (!page) ^~~~ mm/shmem.c:2335:19: note: initialize the variable 'page' to silence this warning struct page *page; ^ = NULL 1 warning generated. vim +/page +2354 mm/shmem.c ^1da177e4c3f41 Linus Torvalds 2005-04-16 2318 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2319 #ifdef CONFIG_USERFAULTFD 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2320 int shmem_mfill_atomic_pte(struct mm_struct *dst_mm, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2321 pmd_t *dst_pmd, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2322 struct vm_area_struct *dst_vma, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2323 unsigned long dst_addr, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2324 unsigned long src_addr, 0b51a78cb242cd Peter Xu 2022-04-29 2325 bool zeropage, bool wp_copy, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2326 struct page **pagep) 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2327 { 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2328 struct inode *inode = file_inode(dst_vma->vm_file); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2329 struct shmem_inode_info *info = SHMEM_I(inode); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2330 struct address_space *mapping = inode->i_mapping; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2331 gfp_t gfp = mapping_gfp_mask(mapping); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2332 pgoff_t pgoff = linear_page_index(dst_vma, dst_addr); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2333 void *page_kaddr; 9a44f3462edc49 Matthew Wilcox (Oracle 2022-04-29 2334) struct folio *folio; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2335 struct page *page; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2336 int ret; 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2337 pgoff_t max_off; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2338 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2339 if (!shmem_inode_acct_block(inode, 1)) { 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2340 /* 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2341 * We may have got a page, returned -ENOENT triggering a retry, 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2342 * and now we find ourselves with -ENOMEM. Release the page, to 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2343 * avoid a BUG_ON in our caller. 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2344 */ 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2345 if (unlikely(*pagep)) { 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2346 put_page(*pagep); 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2347 *pagep = NULL; 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2348 } 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2349 return -ENOMEM; 7ed9d238c7dbb1 Axel Rasmussen 2021-05-14 2350 } 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2351 cb658a453b9327 Andrea Arcangeli 2017-02-22 2352 if (!*pagep) { 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2353 ret = -ENOMEM; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 @2354 if (!page) 0f0796945614b7 Mike Rapoport 2017-09-06 2355 goto out_unacct_blocks; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2356 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2357 if (!zeropage) { /* COPY */ 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2358 page_kaddr = kmap_atomic(page); 8d10396342063c Mike Rapoport 2017-09-06 2359 ret = copy_from_user(page_kaddr, 8d10396342063c Mike Rapoport 2017-09-06 2360 (const void __user *)src_addr, 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2361 PAGE_SIZE); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2362 kunmap_atomic(page_kaddr); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2363 c1e8d7c6a7a682 Michel Lespinasse 2020-06-08 2364 /* fallback to copy_from_user outside mmap_lock */ 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2365 if (unlikely(ret)) { 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2366 *pagep = page; 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2367 ret = -ENOENT; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2368 /* don't free the page */ 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2369 goto out_unacct_blocks; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2370 } 19b482c29b6f38 Muchun Song 2022-03-22 2371 19b482c29b6f38 Muchun Song 2022-03-22 2372 flush_dcache_page(page); 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2373 } else { /* ZEROPAGE */ 19b482c29b6f38 Muchun Song 2022-03-22 2374 clear_user_highpage(page, dst_addr); 8d10396342063c Mike Rapoport 2017-09-06 2375 } 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2376 } else { 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2377 page = *pagep; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2378 *pagep = NULL; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2379 } 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2380 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2381 VM_BUG_ON(PageLocked(page)); 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2382 VM_BUG_ON(PageSwapBacked(page)); 9cc90c664a65f9 Andrea Arcangeli 2017-02-22 2383 __SetPageLocked(page); 9cc90c664a65f9 Andrea Arcangeli 2017-02-22 2384 __SetPageSwapBacked(page); a425d3584e7e69 Andrea Arcangeli 2017-02-22 2385 __SetPageUptodate(page); 9cc90c664a65f9 Andrea Arcangeli 2017-02-22 2386 e2a50c1f64145a Andrea Arcangeli 2018-11-30 2387 ret = -EFAULT; e2a50c1f64145a Andrea Arcangeli 2018-11-30 2388 max_off = DIV_ROUND_UP(i_size_read(inode), PAGE_SIZE); 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2389 if (unlikely(pgoff >= max_off)) e2a50c1f64145a Andrea Arcangeli 2018-11-30 2390 goto out_release; e2a50c1f64145a Andrea Arcangeli 2018-11-30 2391 9a44f3462edc49 Matthew Wilcox (Oracle 2022-04-29 2392) folio = page_folio(page); 9a44f3462edc49 Matthew Wilcox (Oracle 2022-04-29 2393) ret = shmem_add_to_page_cache(folio, mapping, pgoff, NULL, 3fea5a499d57de Johannes Weiner 2020-06-03 2394 gfp & GFP_RECLAIM_MASK, dst_mm); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2395 if (ret) 3fea5a499d57de Johannes Weiner 2020-06-03 2396 goto out_release; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2397 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2398 ret = mfill_atomic_install_pte(dst_mm, dst_pmd, dst_vma, dst_addr, 0b51a78cb242cd Peter Xu 2022-04-29 2399 page, true, wp_copy); 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2400 if (ret) 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2401 goto out_delete_from_cache; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2402 94b7cc01da5a3c Yang Shi 2020-04-20 2403 spin_lock_irq(&info->lock); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2404 info->alloced++; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2405 inode->i_blocks += BLOCKS_PER_PAGE; 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2406 shmem_recalc_inode(inode); 94b7cc01da5a3c Yang Shi 2020-04-20 2407 spin_unlock_irq(&info->lock); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2408 e2a50c1f64145a Andrea Arcangeli 2018-11-30 2409 unlock_page(page); 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2410 return 0; 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2411 out_delete_from_cache: e2a50c1f64145a Andrea Arcangeli 2018-11-30 2412 delete_from_page_cache(page); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2413 out_release: 9cc90c664a65f9 Andrea Arcangeli 2017-02-22 2414 unlock_page(page); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2415 put_page(page); 4c27fe4c4c84f3 Mike Rapoport 2017-02-22 2416 out_unacct_blocks: 0f0796945614b7 Mike Rapoport 2017-09-06 2417 shmem_inode_unacct_blocks(inode, 1); 7d64ae3ab648a9 Axel Rasmussen 2021-06-30 2418 return ret; 8d10396342063c Mike Rapoport 2017-09-06 2419 } 3460f6e5c1ed94 Axel Rasmussen 2021-06-30 2420 #endif /* CONFIG_USERFAULTFD */ 8d10396342063c Mike Rapoport 2017-09-06 2421 :::::: The code at line 2354 was first introduced by commit :::::: 4c27fe4c4c84f3afd504ecff2420cc1ad420d38e userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support :::::: TO: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> :::::: CC: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> -- 0-DAY CI Kernel Test Service https://01.org/lkp
