Hi Thomas, I love your patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.10-rc4] [cannot apply to next-20201113] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/Thomas-Zimmermann/drm-Build-fixe... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git f8394f232b1eab649ce2df5c5f15b0e528c92091 config: arm64-allyesconfig (attached as .config) compiler: aarch64-linux-gcc (GCC) 9.3.0 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://github.com/0day-ci/linux/commit/1e81f225d3ffc9e951faab8deb96ef620... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Thomas-Zimmermann/drm-Build-fixes-for-msm-and-mediatek/20201109-183736 git checkout 1e81f225d3ffc9e951faab8deb96ef6209db7742 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=arm64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): In file included from drivers/gpu/drm/mediatek/mtk_drm_gem.c:14: drivers/gpu/drm/mediatek/mtk_drm_gem.h:48:63: warning: 'struct dma_buf_map' declared inside parameter list will not be visible outside of this definition or declaration 48 | int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map); | ^~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.h:49:66: warning: 'struct dma_buf_map' declared inside parameter list will not be visible outside of this definition or declaration 49 | void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map); | ^~~~~~~~~~~ 232 | int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map) | ^~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.c:232:5: error: conflicting types for 'mtk_drm_gem_prime_vmap' 232 | int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map) | ^~~~~~~~~~~~~~~~~~~~~~ In file included from drivers/gpu/drm/mediatek/mtk_drm_gem.c:14: drivers/gpu/drm/mediatek/mtk_drm_gem.h:48:5: note: previous declaration of 'mtk_drm_gem_prime_vmap' was here 48 | int mtk_drm_gem_prime_vmap(struct drm_gem_object *obj, struct dma_buf_map *map); | ^~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.c: In function 'mtk_drm_gem_prime_vmap': drivers/gpu/drm/mediatek/mtk_drm_gem.c:259:2: error: implicit declaration of function 'dma_buf_map_set_vaddr' [-Werror=implicit-function-declaration] 259 | dma_buf_map_set_vaddr(map, mtk_gem->kvaddr); | ^~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.c: At top level: drivers/gpu/drm/mediatek/mtk_drm_gem.c:264:66: warning: 'struct dma_buf_map' declared inside parameter list will not be visible outside of this definition or declaration 264 | void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map) | ^~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.c:264:6: error: conflicting types for 'mtk_drm_gem_prime_vunmap' 264 | void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map) | ^~~~~~~~~~~~~~~~~~~~~~~~ In file included from drivers/gpu/drm/mediatek/mtk_drm_gem.c:14: drivers/gpu/drm/mediatek/mtk_drm_gem.h:49:6: note: previous declaration of 'mtk_drm_gem_prime_vunmap' was here 49 | void mtk_drm_gem_prime_vunmap(struct drm_gem_object *obj, struct dma_buf_map *map); | ^~~~~~~~~~~~~~~~~~~~~~~~ drivers/gpu/drm/mediatek/mtk_drm_gem.c: In function 'mtk_drm_gem_prime_vunmap': drivers/gpu/drm/mediatek/mtk_drm_gem.c:267:19: error: dereferencing pointer to incomplete type 'struct dma_buf_map' 267 | void *vaddr = map->vaddr; | ^~ cc1: some warnings being treated as errors vim +232 drivers/gpu/drm/mediatek/mtk_drm_gem.c 231 233 { 234 struct mtk_drm_gem_obj *mtk_gem = to_mtk_gem_obj(obj); 235 struct sg_table *sgt = NULL; 236 unsigned int npages; 237 238 if (mtk_gem->kvaddr) 239 goto out; 240 241 sgt = mtk_gem_prime_get_sg_table(obj); 242 if (IS_ERR(sgt)) 243 return PTR_ERR(sgt); 244 245 npages = obj->size >> PAGE_SHIFT; 246 mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL); 247 if (!mtk_gem->pages) { 248 kfree(sgt); 249 return -ENOMEM; 250 } 251 252 drm_prime_sg_to_page_addr_arrays(sgt, mtk_gem->pages, NULL, npages); 253 254 mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP, 255 pgprot_writecombine(PAGE_KERNEL)); 256 257 out: 258 kfree(sgt); 259 dma_buf_map_set_vaddr(map, mtk_gem->kvaddr); 260 261 return 0; 262 } 263 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org