Hi, Thank you for the patch! Yet something to improve: [auto build test ERROR on mmotm/master] [also build test ERROR on linus/master v5.5-rc6 next-20200110] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system. BTW, we also suggest to use '--base' option to specify the base tree in git format-patch, please see https://stackoverflow.com/a/37406982] url: https://github.com/0day-ci/linux/commits/buddy-zhang-aliyun-com/mm-cma-c-find-a-named-CMA-area-by-name/20200114-155334 base: git://git.cmpxchg.org/linux-mmotm.git master config: i386-randconfig-a002-20200115 (attached as .config) compiler: gcc-7 (Debian 7.5.0-3) 7.5.0 reproduce: # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag Reported-by: kbuild test robot All errors (new ones prefixed by >>): mm/cma.c:55:1: error: expected ';' before 'phys_addr_t' phys_addr_t cma_get_base(const struct cma *cma) ^~~~~~~~~~~ mm/cma.c: In function 'cma_alloc': mm/cma.c:449:9: error: implicit declaration of function 'cma_bitmap_aligned_mask'; did you mean 'cma_bitmap_maxno'? [-Werror=implicit-function-declaration] mask = cma_bitmap_aligned_mask(cma, align); ^~~~~~~~~~~~~~~~~~~~~~~ cma_bitmap_maxno mm/cma.c:450:11: error: implicit declaration of function 'cma_bitmap_aligned_offset'; did you mean 'cma_bitmap_maxno'? [-Werror=implicit-function-declaration] offset = cma_bitmap_aligned_offset(cma, align); ^~~~~~~~~~~~~~~~~~~~~~~~~ cma_bitmap_maxno mm/cma.c:452:17: error: implicit declaration of function 'cma_bitmap_pages_to_bits'; did you mean 'cma_bitmap_maxno'? [-Werror=implicit-function-declaration] bitmap_count = cma_bitmap_pages_to_bits(cma, count); ^~~~~~~~~~~~~~~~~~~~~~~~ cma_bitmap_maxno >> mm/cma.c:484:3: error: implicit declaration of function 'cma_clear_bitmap'; did you mean 'cr4_clear_bits'? [-Werror=implicit-function-declaration] cma_clear_bitmap(cma, pfn, count); ^~~~~~~~~~~~~~~~ cr4_clear_bits cc1: some warnings being treated as errors vim +484 mm/cma.c dbe43d4d2837da Jaewon Kim 2017-02-24 418 a254129e8686bf Joonsoo Kim 2014-08-06 419 /** a254129e8686bf Joonsoo Kim 2014-08-06 420 * cma_alloc() - allocate pages from contiguous area a254129e8686bf Joonsoo Kim 2014-08-06 421 * @cma: Contiguous memory region for which the allocation is performed. a254129e8686bf Joonsoo Kim 2014-08-06 422 * @count: Requested number of pages. a254129e8686bf Joonsoo Kim 2014-08-06 423 * @align: Requested alignment of pages (in PAGE_SIZE order). 6518202970c105 Marek Szyprowski 2018-08-17 424 * @no_warn: Avoid printing message about failed allocation a254129e8686bf Joonsoo Kim 2014-08-06 425 * a254129e8686bf Joonsoo Kim 2014-08-06 426 * This function allocates part of contiguous memory on specific a254129e8686bf Joonsoo Kim 2014-08-06 427 * contiguous memory area. a254129e8686bf Joonsoo Kim 2014-08-06 428 */ e2f466e32f56c8 Lucas Stach 2017-02-24 429 struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align, 6518202970c105 Marek Szyprowski 2018-08-17 430 bool no_warn) a254129e8686bf Joonsoo Kim 2014-08-06 431 { 3acaea6804b3a1 Andrew Morton 2015-11-05 432 unsigned long mask, offset; 3acaea6804b3a1 Andrew Morton 2015-11-05 433 unsigned long pfn = -1; 3acaea6804b3a1 Andrew Morton 2015-11-05 434 unsigned long start = 0; a254129e8686bf Joonsoo Kim 2014-08-06 435 unsigned long bitmap_maxno, bitmap_no, bitmap_count; 2813b9c0296259 Andrey Konovalov 2018-12-28 436 size_t i; a254129e8686bf Joonsoo Kim 2014-08-06 437 struct page *page = NULL; dbe43d4d2837da Jaewon Kim 2017-02-24 438 int ret = -ENOMEM; a254129e8686bf Joonsoo Kim 2014-08-06 439 a254129e8686bf Joonsoo Kim 2014-08-06 440 if (!cma || !cma->count) a254129e8686bf Joonsoo Kim 2014-08-06 441 return NULL; a254129e8686bf Joonsoo Kim 2014-08-06 442 67a2e213e7e937 Rohit Vaswani 2015-10-22 443 pr_debug("%s(cma %p, count %zu, align %d)\n", __func__, (void *)cma, a254129e8686bf Joonsoo Kim 2014-08-06 444 count, align); a254129e8686bf Joonsoo Kim 2014-08-06 445 a254129e8686bf Joonsoo Kim 2014-08-06 446 if (!count) a254129e8686bf Joonsoo Kim 2014-08-06 447 return NULL; a254129e8686bf Joonsoo Kim 2014-08-06 448 a254129e8686bf Joonsoo Kim 2014-08-06 449 mask = cma_bitmap_aligned_mask(cma, align); b5be83e308f70e Gregory Fong 2014-12-12 @450 offset = cma_bitmap_aligned_offset(cma, align); a254129e8686bf Joonsoo Kim 2014-08-06 451 bitmap_maxno = cma_bitmap_maxno(cma); a254129e8686bf Joonsoo Kim 2014-08-06 452 bitmap_count = cma_bitmap_pages_to_bits(cma, count); a254129e8686bf Joonsoo Kim 2014-08-06 453 6b36ba599d602d Shiraz Hashim 2016-11-10 454 if (bitmap_count > bitmap_maxno) 6b36ba599d602d Shiraz Hashim 2016-11-10 455 return NULL; 6b36ba599d602d Shiraz Hashim 2016-11-10 456 a254129e8686bf Joonsoo Kim 2014-08-06 457 for (;;) { a254129e8686bf Joonsoo Kim 2014-08-06 458 mutex_lock(&cma->lock); b5be83e308f70e Gregory Fong 2014-12-12 459 bitmap_no = bitmap_find_next_zero_area_off(cma->bitmap, b5be83e308f70e Gregory Fong 2014-12-12 460 bitmap_maxno, start, bitmap_count, mask, b5be83e308f70e Gregory Fong 2014-12-12 461 offset); a254129e8686bf Joonsoo Kim 2014-08-06 462 if (bitmap_no >= bitmap_maxno) { a254129e8686bf Joonsoo Kim 2014-08-06 463 mutex_unlock(&cma->lock); a254129e8686bf Joonsoo Kim 2014-08-06 464 break; a254129e8686bf Joonsoo Kim 2014-08-06 465 } a254129e8686bf Joonsoo Kim 2014-08-06 466 bitmap_set(cma->bitmap, bitmap_no, bitmap_count); a254129e8686bf Joonsoo Kim 2014-08-06 467 /* a254129e8686bf Joonsoo Kim 2014-08-06 468 * It's safe to drop the lock here. We've marked this region for a254129e8686bf Joonsoo Kim 2014-08-06 469 * our exclusive use. If the migration fails we will take the a254129e8686bf Joonsoo Kim 2014-08-06 470 * lock again and unmark it. a254129e8686bf Joonsoo Kim 2014-08-06 471 */ a254129e8686bf Joonsoo Kim 2014-08-06 472 mutex_unlock(&cma->lock); a254129e8686bf Joonsoo Kim 2014-08-06 473 a254129e8686bf Joonsoo Kim 2014-08-06 474 pfn = cma->base_pfn + (bitmap_no << cma->order_per_bit); a254129e8686bf Joonsoo Kim 2014-08-06 475 mutex_lock(&cma_mutex); ca96b625341027 Lucas Stach 2017-02-24 476 ret = alloc_contig_range(pfn, pfn + count, MIGRATE_CMA, 6518202970c105 Marek Szyprowski 2018-08-17 477 GFP_KERNEL | (no_warn ? __GFP_NOWARN : 0)); a254129e8686bf Joonsoo Kim 2014-08-06 478 mutex_unlock(&cma_mutex); a254129e8686bf Joonsoo Kim 2014-08-06 479 if (ret == 0) { a254129e8686bf Joonsoo Kim 2014-08-06 480 page = pfn_to_page(pfn); a254129e8686bf Joonsoo Kim 2014-08-06 481 break; a254129e8686bf Joonsoo Kim 2014-08-06 482 } b7155e76a702d9 Joonsoo Kim 2014-08-06 483 a254129e8686bf Joonsoo Kim 2014-08-06 @484 cma_clear_bitmap(cma, pfn, count); b7155e76a702d9 Joonsoo Kim 2014-08-06 485 if (ret != -EBUSY) b7155e76a702d9 Joonsoo Kim 2014-08-06 486 break; b7155e76a702d9 Joonsoo Kim 2014-08-06 487 a254129e8686bf Joonsoo Kim 2014-08-06 488 pr_debug("%s(): memory range at %p is busy, retrying\n", a254129e8686bf Joonsoo Kim 2014-08-06 489 __func__, pfn_to_page(pfn)); a254129e8686bf Joonsoo Kim 2014-08-06 490 /* try again with a bit different memory target */ a254129e8686bf Joonsoo Kim 2014-08-06 491 start = bitmap_no + mask + 1; a254129e8686bf Joonsoo Kim 2014-08-06 492 } a254129e8686bf Joonsoo Kim 2014-08-06 493 3acaea6804b3a1 Andrew Morton 2015-11-05 494 trace_cma_alloc(pfn, page, count, align); 99e8ea6cd2210c Stefan Strogin 2015-04-15 495 2813b9c0296259 Andrey Konovalov 2018-12-28 496 /* 2813b9c0296259 Andrey Konovalov 2018-12-28 497 * CMA can allocate multiple page blocks, which results in different 2813b9c0296259 Andrey Konovalov 2018-12-28 498 * blocks being marked with different tags. Reset the tags to ignore 2813b9c0296259 Andrey Konovalov 2018-12-28 499 * those page blocks. 2813b9c0296259 Andrey Konovalov 2018-12-28 500 */ 2813b9c0296259 Andrey Konovalov 2018-12-28 501 if (page) { 2813b9c0296259 Andrey Konovalov 2018-12-28 502 for (i = 0; i < count; i++) 2813b9c0296259 Andrey Konovalov 2018-12-28 503 page_kasan_tag_reset(page + i); 2813b9c0296259 Andrey Konovalov 2018-12-28 504 } 2813b9c0296259 Andrey Konovalov 2018-12-28 505 6518202970c105 Marek Szyprowski 2018-08-17 506 if (ret && !no_warn) { 5984af1082f3b1 Pintu Agarwal 2017-11-15 507 pr_err("%s: alloc failed, req-size: %zu pages, ret: %d\n", dbe43d4d2837da Jaewon Kim 2017-02-24 508 __func__, count, ret); dbe43d4d2837da Jaewon Kim 2017-02-24 509 cma_debug_show_areas(cma); dbe43d4d2837da Jaewon Kim 2017-02-24 510 } dbe43d4d2837da Jaewon Kim 2017-02-24 511 a254129e8686bf Joonsoo Kim 2014-08-06 512 pr_debug("%s(): returned %p\n", __func__, page); a254129e8686bf Joonsoo Kim 2014-08-06 513 return page; a254129e8686bf Joonsoo Kim 2014-08-06 514 } a254129e8686bf Joonsoo Kim 2014-08-06 515 :::::: The code at line 484 was first introduced by commit :::::: a254129e8686bff7a340b58f35241b04927e81c0 CMA: generalize CMA reserved area management functionality :::::: TO: Joonsoo Kim :::::: CC: Linus Torvalds --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org Intel Corporation