[linux-next:master 3141/6048] drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:159:37: warning: unused variable 'amdgpu_securedisplay_debugfs_ops'

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master
head:   59fa6a163ffabc1bf25c5e0e33899e268a96d3cc
commit: ecaafb7b5ab6406587341d8727f237b3ee00dedf [3141/6048] drm/amdgpu: Add secure display TA interface
config: s390-randconfig-r011-20210125 (attached as .config)
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project 12d0753aca22896fda2cf76781b0ee0524d55065)
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://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git/commit/?id=ecaafb7b5ab6406587341d8727f237b3ee00dedf
        git remote add linux-next https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git
        git fetch --no-tags linux-next master
        git checkout ecaafb7b5ab6406587341d8727f237b3ee00dedf
        # save the attached .config to linux build tree
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=s390 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <redacted>

All warnings (new ones prefixed by >>):

   include/uapi/linux/swab.h:19:12: note: expanded from macro '___constant_swab32'
           (((__u32)(x) & (__u32)0x000000ffUL) << 24) |            \
                     ^
   In file included from drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:27:
   In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:52:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   In file included from arch/s390/include/asm/io.h:80:
   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:34:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32'
           ___constant_swab32(x) :                 \
                              ^
   include/uapi/linux/swab.h:20:12: note: expanded from macro '___constant_swab32'
           (((__u32)(x) & (__u32)0x0000ff00UL) <<  8) |            \
                     ^
   In file included from drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:27:
   In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:52:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   In file included from arch/s390/include/asm/io.h:80:
   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:34:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32'
           ___constant_swab32(x) :                 \
                              ^
   include/uapi/linux/swab.h:21:12: note: expanded from macro '___constant_swab32'
           (((__u32)(x) & (__u32)0x00ff0000UL) >>  8) |            \
                     ^
   In file included from drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:27:
   In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:52:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   In file included from arch/s390/include/asm/io.h:80:
   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:34:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:119:21: note: expanded from macro '__swab32'
           ___constant_swab32(x) :                 \
                              ^
   include/uapi/linux/swab.h:22:12: note: expanded from macro '___constant_swab32'
           (((__u32)(x) & (__u32)0xff000000UL) >> 24)))
                     ^
   In file included from drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:27:
   In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:52:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   In file included from arch/s390/include/asm/io.h:80:
   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:34:59: note: expanded from macro '__le32_to_cpu'
   #define __le32_to_cpu(x) __swab32((__force __u32)(__le32)(x))
                                                             ^
   include/uapi/linux/swab.h:120:12: note: expanded from macro '__swab32'
           __fswab32(x))
                     ^
   In file included from drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:27:
   In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:52:
   In file included from include/linux/pci.h:39:
   In file included from include/linux/io.h:13:
   In file included from arch/s390/include/asm/io.h:80:
   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);
                   ~~~~~~~~~~ ^

quoted

drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c:159:37: warning: unused variable 'amdgpu_securedisplay_debugfs_ops' [-Wunused-const-variable]

   static const struct file_operations amdgpu_securedisplay_debugfs_ops = {
                                       ^
   21 warnings generated.


vim +/amdgpu_securedisplay_debugfs_ops +159 drivers/gpu/drm/amd/amdgpu/amdgpu_securedisplay.c

   158	
 > 159	static const struct file_operations amdgpu_securedisplay_debugfs_ops = {
   160		.owner = THIS_MODULE,
   161		.read = NULL,
   162		.write = amdgpu_securedisplay_debugfs_write,
   163		.llseek = default_llseek
   164	};
   165	

---
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