tree: git://git.infradead.org/users/hch/misc.git dma_alloc_pages head: 9321e87b6405e6a6af978c0221fac97faef5a5e3 commit: aadd1578979b47af197cf5acedc2a63d068e357e [/6] dma-mapping: add a new dma_alloc_pages API config: powerpc-allmodconfig (attached as .config) compiler: powerpc64-linux-gcc (GCC) 7.4.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout aadd1578979b47af197cf5acedc2a63d068e357e # save the attached .config to linux build tree GCC_VERSION=7.4.0 make.cross ARCH=powerpc If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp(a)intel.com&gt; Note: the hch-misc/dma_alloc_pages HEAD 9321e87b6405e6a6af978c0221fac97faef5a5e3 builds fine. It only hurts bisectibility. All errors (new ones prefixed by >>): kernel/dma/mapping.c: In function 'dma_alloc_pages': kernel/dma/mapping.c:387:9: error: implicit declaration of function 'dma_alloc_contiguous'; did you mean 'dma_alloc_coherent'? [-Werror=implicit-function-declaration] return dma_alloc_contiguous(dev, size, gfp); ^~~~~~~~~~~~~~~~~~~~ dma_alloc_coherent kernel/dma/mapping.c:387:9: warning: return makes pointer from integer without a cast [-Wint-conversion] return dma_alloc_contiguous(dev, size, gfp); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ kernel/dma/mapping.c: In function 'dma_free_pages': dma_free_contiguous(dev, page, size); ^~~~~~~~~~~~~~~~~~~ set_zone_contiguous cc1: some warnings being treated as errors vim +399 kernel/dma/mapping.c 347 348 /** 349 * dma_alloc_pages - allocate memory that is DMA addressable by a device 350 * @dev: device the memory is allocated for 351 * @size: size of the memory to be allocated 352 * @gfp: GFP_* mask for the memory allocation 353 * 354 * This function allocates memory which is guaranteed to be DMA addressable 355 * by @dev when later mapped for DMA using the dma_map_page(), dma_map_single(), 356 * or dma_map_sg() functions. 357 */ 358 struct page *dma_alloc_pages(struct device *dev, size_t size, gfp_t gfp) 359 { 360 const struct dma_map_ops *ops = get_dma_ops(dev); 361 362 /* let the implementation decide on the zone to allocate from: */ 363 if (WARN_ON_ONCE(gfp & (__GFP_DMA | __GFP_DMA32))) 364 return NULL; 365 366 /* we must zero all memory to avoid information leaks */ 367 gfp |= __GFP_ZERO; 368 369 if (dma_is_direct(ops)) 370 return dma_direct_alloc_pages(dev, size, gfp); 371 372 /* 373 * Must return a page from the page allocator or CMA. 374 */ 375 if (ops->alloc_pages) 376 return ops->alloc_pages(dev, size, gfp); 377 378 /* 379 * Everything that looks remotely like an IOMMU should be able to map 380 * any system memory into at least 32-bit of dma_addr_t. 381 */ 382 if (dev->coherent_dma_mask < 32) { 383 dev_warn(dev, "can't support DMA page allocation for DMA mask < 32-bit\n"); 384 return NULL; 385 } 386 388 } 389 EXPORT_SYMBOL_GPL(dma_alloc_pages); 390 391 /** 392 * dma_free_pages - free memory allocated by dma_alloc_pages() 393 * @dev: device the memory is allocated for 394 * @page: the memory to be freed 395 * @size: size of the memory to be freed 396 */ 397 void dma_free_pages(struct device *dev, struct page *page, size_t size) 398 { 400 } 401 EXPORT_SYMBOL_GPL(dma_free_pages); 402 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation