Hi Christian, I love your patch! Perhaps something to improve: [auto build test WARNING on drm-misc/drm-misc-next] [also build test WARNING on media-tree/master drm-tip/drm-tip linus/master v6.2-rc5] [cannot apply to next-20230123] [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#_base_tree_information] url: https://github.com/intel-lab-lkp/linux/commits/Christian-K-nig/media-uvcvideo-expose-dma-heap-hint-to-userspace/20230123-213836 base: git://anongit.freedesktop.org/drm/drm-misc drm-misc-next patch link: https://lore.kernel.org/r/20230123123756.401692-3-christian.koenig%40amd.com patch subject: [PATCH 2/2] media: uvcvideo: expose dma-heap hint to userspace config: i386-randconfig-a002-20230123 (https://download.01.org/0day-ci/archive/20230124/202301241137.qT2rnQ5T-lkp@xxxxxxxxx/config) compiler: gcc-11 (Debian 11.3.0-8) 11.3.0 reproduce (this is a W=1 build): # https://github.com/intel-lab-lkp/linux/commit/adc04dccd892eec7f84c6ec112b48df376172e48 git remote add linux-review https://github.com/intel-lab-lkp/linux git fetch --no-tags linux-review Christian-K-nig/media-uvcvideo-expose-dma-heap-hint-to-userspace/20230123-213836 git checkout adc04dccd892eec7f84c6ec112b48df376172e48 # save the config file mkdir build_dir && cp config build_dir/.config make W=1 O=build_dir ARCH=i386 olddefconfig make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash drivers/media/usb/uvc/ If you fix the issue, kindly add following tag where applicable | Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): In file included from drivers/media/usb/uvc/uvc_driver.c:10: >> include/linux/dma-heap.h:92:5: warning: no previous prototype for 'dma_heap_create_device_link' [-Wmissing-prototypes] 92 | int dma_heap_create_device_link(struct device *dev, const char *heap) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ >> include/linux/dma-heap.h:97:6: warning: no previous prototype for 'dma_heap_remove_device_link' [-Wmissing-prototypes] 97 | void dma_heap_remove_device_link(struct device *dev) | ^~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +/dma_heap_create_device_link +92 include/linux/dma-heap.h 4ce5c5c0cf31f4 Christian König 2023-01-23 91 4ce5c5c0cf31f4 Christian König 2023-01-23 @92 int dma_heap_create_device_link(struct device *dev, const char *heap) 4ce5c5c0cf31f4 Christian König 2023-01-23 93 { 4ce5c5c0cf31f4 Christian König 2023-01-23 94 return 0; 4ce5c5c0cf31f4 Christian König 2023-01-23 95 } 4ce5c5c0cf31f4 Christian König 2023-01-23 96 4ce5c5c0cf31f4 Christian König 2023-01-23 @97 void dma_heap_remove_device_link(struct device *dev) 4ce5c5c0cf31f4 Christian König 2023-01-23 98 { 4ce5c5c0cf31f4 Christian König 2023-01-23 99 } 4ce5c5c0cf31f4 Christian König 2023-01-23 100 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests