Hi Michael, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on drm-tip/drm-tip] [also build test WARNING on drm/drm-next] [cannot apply to drm-intel/for-linux-next v5.17-rc5 next-20220222] [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/Michael-Cheng/Use-drm_clflush-instead-of-clflush/20220223-140110 base: git://anongit.freedesktop.org/drm/drm-tip drm-tip config: s390-randconfig-r013-20220221 (https://download.01.org/0day-ci/archive/20220223/202202231817.dkY1qGrU-lkp@xxxxxxxxx/config) compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project d271fc04d5b97b12e6b797c6067d3c96a8d7470e) 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 # install s390 cross compiling tool for clang build # apt-get install binutils-s390x-linux-gnu # https://github.com/0day-ci/linux/commit/f4c92ba1f52db578a26ac9944e2cbe52c548e8e9 git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Michael-Cheng/Use-drm_clflush-instead-of-clflush/20220223-140110 git checkout f4c92ba1f52db578a26ac9944e2cbe52c548e8e9 # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=s390 SHELL=/bin/bash drivers/gpu/drm/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp@xxxxxxxxx> All warnings (new ones prefixed by >>): In file included from drivers/gpu/drm/drm_cache.c:31: >> include/linux/cacheflush.h:12:46: warning: declaration of 'struct folio' will not be visible outside of this function [-Wvisibility] static inline void flush_dcache_folio(struct folio *folio) ^ In file included from drivers/gpu/drm/drm_cache.c:35: In file included from include/linux/iosys-map.h:9: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:464:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __raw_readb(PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:477:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:37:59: note: expanded from macro '__le16_to_cpu' #define __le16_to_cpu(x) __swab16((__force __u16)(__le16)(x)) ^ include/uapi/linux/swab.h:102:54: note: expanded from macro '__swab16' #define __swab16(x) (__u16)__builtin_bswap16((__u16)(x)) ^ In file included from drivers/gpu/drm/drm_cache.c:35: In file included from include/linux/iosys-map.h:9: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:490:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); ~~~~~~~~~~ ^ include/uapi/linux/byteorder/big_endian.h:35:59: note: expanded from macro '__le32_to_cpu' #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x)) ^ include/uapi/linux/swab.h:115:54: note: expanded from macro '__swab32' #define __swab32(x) (__u32)__builtin_bswap32((__u32)(x)) ^ In file included from drivers/gpu/drm/drm_cache.c:35: In file included from include/linux/iosys-map.h:9: In file included from include/linux/io.h:13: In file included from arch/s390/include/asm/io.h:75: include/asm-generic/io.h:501:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writeb(value, PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:511:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:521:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); ~~~~~~~~~~ ^ include/asm-generic/io.h:609:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:617:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:625:20: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] readsl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:634:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesb(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:643:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesw(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ include/asm-generic/io.h:652:21: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] writesl(PCI_IOBASE + addr, buffer, count); ~~~~~~~~~~ ^ 13 warnings generated. vim +12 include/linux/cacheflush.h 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 6) 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 7) #if ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 8) #ifndef ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 9) void flush_dcache_folio(struct folio *folio); 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 10) #endif 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 11) #else 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 @12) static inline void flush_dcache_folio(struct folio *folio) 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 13) { 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 14) } 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 15) #define ARCH_IMPLEMENTS_FLUSH_DCACHE_FOLIO 0 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 16) #endif /* ARCH_IMPLEMENTS_FLUSH_DCACHE_PAGE */ 522a0032af0055 Matthew Wilcox (Oracle 2021-11-06 17) --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
