Hi bo, FYI, the error/warning still remains. tree: https://github.com/intel/linux-intel-lts.git 4.19/android_q head: 4701bbfe016302fc3a965c193f9dea53bd96dbb9 commit: ab2f796a9d1298c6e238cd2a770cbf3666393c02 [9364/16908] ion: fix the tons of warning from PAT config: m68k-allmodconfig (attached as .config) compiler: m68k-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 git checkout ab2f796a9d1298c6e238cd2a770cbf3666393c02 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=m68k If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): In file included from arch/m68k/include/asm/io_mm.h:25, from arch/m68k/include/asm/io.h:8, from include/linux/scatterlist.h:9, from include/linux/dma-mapping.h:11, from drivers/staging/android/ion/ion_system_heap.c:9: arch/m68k/include/asm/raw_io.h: In function 'raw_rom_outsb': arch/m68k/include/asm/raw_io.h:83:7: warning: variable '__w' set but not used [-Wunused-but-set-variable] 83 | ({u8 __w, __v = (b); u32 _addr = ((u32) (addr)); \ | ^~~ arch/m68k/include/asm/raw_io.h:399:3: note: in expansion of macro 'rom_out_8' 399 | rom_out_8(port, *buf++); | ^~~~~~~~~ arch/m68k/include/asm/raw_io.h: In function 'raw_rom_outsw': arch/m68k/include/asm/raw_io.h:86:8: warning: variable '__w' set but not used [-Wunused-but-set-variable] 86 | ({u16 __w, __v = (w); u32 _addr = ((u32) (addr)); \ | ^~~ arch/m68k/include/asm/raw_io.h:417:3: note: in expansion of macro 'rom_out_be16' 417 | rom_out_be16(port, *buf++); | ^~~~~~~~~~~~ arch/m68k/include/asm/raw_io.h: In function 'raw_rom_outsw_swapw': arch/m68k/include/asm/raw_io.h:90:8: warning: variable '__w' set but not used [-Wunused-but-set-variable] 90 | ({u16 __w, __v = (w); u32 _addr = ((u32) (addr)); \ | ^~~ arch/m68k/include/asm/raw_io.h:435:3: note: in expansion of macro 'rom_out_le16' 435 | rom_out_le16(port, *buf++); | ^~~~~~~~~~~~ In file included from arch/m68k/include/asm/page_mm.h:7, from arch/m68k/include/asm/page.h:47, from drivers/staging/android/ion/ion_system_heap.c:8: include/linux/scatterlist.h: In function 'sg_set_buf': arch/m68k/include/asm/page_mm.h:169:49: warning: ordered comparison of pointer with null pointer [-Wextra] 169 | #define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory) | ^~ include/linux/compiler.h:77:42: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/scatterlist.h:143:2: note: in expansion of macro 'BUG_ON' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~ include/linux/scatterlist.h:143:10: note: in expansion of macro 'virt_addr_valid' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~~~~~~~~~~ include/linux/dma-mapping.h: In function 'dma_map_resource': arch/m68k/include/asm/page_mm.h:169:49: warning: ordered comparison of pointer with null pointer [-Wextra] 169 | #define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && (void *)(kaddr) < high_memory) | ^~ include/linux/compiler.h:77:42: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/dma-mapping.h:329:2: note: in expansion of macro 'BUG_ON' 329 | BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); | ^~~~~~ arch/m68k/include/asm/page_mm.h:170:25: note: in expansion of macro 'virt_addr_valid' 170 | #define pfn_valid(pfn) virt_addr_valid(pfn_to_virt(pfn)) | ^~~~~~~~~~~~~~~ include/linux/dma-mapping.h:329:9: note: in expansion of macro 'pfn_valid' 329 | BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); | ^~~~~~~~~ drivers/staging/android/ion/ion_system_heap.c: At top level: 17 | #include <asm/set_memory.h> | ^~~~~~~~~~~~~~~~~~ compilation terminated. vim +17 drivers/staging/android/ion/ion_system_heap.c 18 #include "ion.h" 19 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org