Re: [PATCH v11 1/6] drm: Add arch arm64 for drm_clflush_virt_range

[kernel test robot <lkp@intel.com>]

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@intel.com/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@intel.com>

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
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