tree: https://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git xfs-5.4-fixes head: 6350744c66a41ac4d044bd083852a5cc20bd5b93 commit: b4d5a0a3dc269e8127f89060cb690a19221fd433 [4/7] xfs: assure zeroed memory buffers for certain kmem allocations reproduce: # apt-get install sparse # sparse version: v0.6.1-rc1-42-g38eda53-dirty git checkout b4d5a0a3dc269e8127f89060cb690a19221fd433 make ARCH=x86_64 allmodconfig make C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp@xxxxxxxxx> sparse warnings: (new ones prefixed by >>) >> fs/xfs/xfs_buf.c:354:29: sparse: sparse: invalid assignment: |= >> fs/xfs/xfs_buf.c:354:29: sparse: left side has type unsigned int >> fs/xfs/xfs_buf.c:354:29: sparse: right side has type restricted xfs_km_flags_t >> fs/xfs/xfs_buf.c:367:44: sparse: sparse: restricted xfs_km_flags_t degrades to integer >> fs/xfs/xfs_buf.c:367:52: sparse: sparse: incorrect type in argument 3 (different base types) @@ expected restricted xfs_km_flags_t [usertype] flags @@ got [usertype] flags @@ >> fs/xfs/xfs_buf.c:367:52: sparse: expected restricted xfs_km_flags_t [usertype] flags >> fs/xfs/xfs_buf.c:367:52: sparse: got unsigned int vim +354 fs/xfs/xfs_buf.c 333 334 /* 335 * Allocates all the pages for buffer in question and builds it's page list. 336 */ 337 STATIC int 338 xfs_buf_allocate_memory( 339 xfs_buf_t *bp, 340 uint flags) 341 { 342 size_t size; 343 size_t nbytes, offset; 344 gfp_t gfp_mask = xb_to_gfp(flags); 345 unsigned short page_count, i; 346 xfs_off_t start, end; 347 int error; 348 uint kmflag_mask = 0; 349 350 /* 351 * assure zeroed buffer for non-read cases. 352 */ 353 if (!(flags & XBF_READ)) { > 354 kmflag_mask |= KM_ZERO; 355 gfp_mask |= __GFP_ZERO; 356 } 357 358 /* 359 * for buffers that are contained within a single page, just allocate 360 * the memory from the heap - there's no need for the complexity of 361 * page arrays to keep allocation down to order 0. 362 */ 363 size = BBTOB(bp->b_length); 364 if (size < PAGE_SIZE) { 365 int align_mask = xfs_buftarg_dma_alignment(bp->b_target); 366 bp->b_addr = kmem_alloc_io(size, align_mask, > 367 KM_NOFS | kmflag_mask); 368 if (!bp->b_addr) { 369 /* low memory - use alloc_page loop instead */ 370 goto use_alloc_page; 371 } 372 373 if (((unsigned long)(bp->b_addr + size - 1) & PAGE_MASK) != 374 ((unsigned long)bp->b_addr & PAGE_MASK)) { 375 /* b_addr spans two pages - use alloc_page instead */ 376 kmem_free(bp->b_addr); 377 bp->b_addr = NULL; 378 goto use_alloc_page; 379 } 380 bp->b_offset = offset_in_page(bp->b_addr); 381 bp->b_pages = bp->b_page_array; 382 bp->b_pages[0] = kmem_to_page(bp->b_addr); 383 bp->b_page_count = 1; 384 bp->b_flags |= _XBF_KMEM; 385 return 0; 386 } 387 388 use_alloc_page: 389 start = BBTOB(bp->b_maps[0].bm_bn) >> PAGE_SHIFT; 390 end = (BBTOB(bp->b_maps[0].bm_bn + bp->b_length) + PAGE_SIZE - 1) 391 >> PAGE_SHIFT; 392 page_count = end - start; 393 error = _xfs_buf_get_pages(bp, page_count); 394 if (unlikely(error)) 395 return error; 396 397 offset = bp->b_offset; 398 bp->b_flags |= _XBF_PAGES; 399 400 for (i = 0; i < bp->b_page_count; i++) { 401 struct page *page; 402 uint retries = 0; 403 retry: 404 page = alloc_page(gfp_mask); 405 if (unlikely(page == NULL)) { 406 if (flags & XBF_READ_AHEAD) { 407 bp->b_page_count = i; 408 error = -ENOMEM; 409 goto out_free_pages; 410 } 411 412 /* 413 * This could deadlock. 414 * 415 * But until all the XFS lowlevel code is revamped to 416 * handle buffer allocation failures we can't do much. 417 */ 418 if (!(++retries % 100)) 419 xfs_err(NULL, 420 "%s(%u) possible memory allocation deadlock in %s (mode:0x%x)", 421 current->comm, current->pid, 422 __func__, gfp_mask); 423 424 XFS_STATS_INC(bp->b_mount, xb_page_retries); 425 congestion_wait(BLK_RW_ASYNC, HZ/50); 426 goto retry; 427 } 428 429 XFS_STATS_INC(bp->b_mount, xb_page_found); 430 431 nbytes = min_t(size_t, size, PAGE_SIZE - offset); 432 size -= nbytes; 433 bp->b_pages[i] = page; 434 offset = 0; 435 } 436 return 0; 437 438 out_free_pages: 439 for (i = 0; i < bp->b_page_count; i++) 440 __free_page(bp->b_pages[i]); 441 bp->b_flags &= ~_XBF_PAGES; 442 return error; 443 } 444 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
