Hi Dave, FYI, the error/warning still remains. tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 1e28eed17697bcf343c6743f0028cc3b5dd88bf0 commit: 0c8d22fcae2f9590a07b000e1724f665820b77f7 Merge tag 'amd-drm-next-5.10-2020-09-03' of git://people.freedesktop.org/~agd5f/linux into drm-next date: 6 months ago config: s390-randconfig-r011-20210315 (attached as .config) compiler: clang version 13.0.0 (https://github.com/llvm/llvm-project a28facba1ccdc957f386b7753f4958307f1bfde8) 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/torvalds/linux.git/commit/?id=0c8d22fcae2f9590a07b000e1724f665820b77f7 git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 0c8d22fcae2f9590a07b000e1724f665820b77f7 # 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 All warnings (new ones prefixed by >>): In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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_rap.c:27: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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_rap.c:27: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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_rap.c:27: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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_rap.c:27: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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); ~~~~~~~~~~ ^ >> drivers/gpu/drm/amd/amdgpu/amdgpu_rap.c:109:37: warning: unused variable 'amdgpu_rap_debugfs_ops' [-Wunused-const-variable] static const struct file_operations amdgpu_rap_debugfs_ops = { ^ 21 warnings generated. -- In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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/../pm/amdgpu_pm.c:28: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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/../pm/amdgpu_pm.c:28: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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/../pm/amdgpu_pm.c:28: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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/../pm/amdgpu_pm.c:28: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu.h:69: In file included from drivers/gpu/drm/amd/amdgpu/../amdgpu/amdgpu_mode.h:33: In file included from include/drm/drm_crtc.h:31: In file included from include/linux/fb.h:17: In file included from arch/s390/include/asm/io.h:72: 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); ~~~~~~~~~~ ^ >> drivers/gpu/drm/amd/amdgpu/../pm/amdgpu_pm.c:41:34: warning: unused variable 'clocks' [-Wunused-const-variable] static const struct cg_flag_name clocks[] = { ^ 21 warnings generated. vim +/amdgpu_rap_debugfs_ops +109 drivers/gpu/drm/amd/amdgpu/amdgpu_rap.c a4322e1881bed8 Wenhui Sheng 2020-08-11 108 a4322e1881bed8 Wenhui Sheng 2020-08-11 @109 static const struct file_operations amdgpu_rap_debugfs_ops = { a4322e1881bed8 Wenhui Sheng 2020-08-11 110 .owner = THIS_MODULE, a4322e1881bed8 Wenhui Sheng 2020-08-11 111 .read = NULL, a4322e1881bed8 Wenhui Sheng 2020-08-11 112 .write = amdgpu_rap_debugfs_write, a4322e1881bed8 Wenhui Sheng 2020-08-11 113 .llseek = default_llseek a4322e1881bed8 Wenhui Sheng 2020-08-11 114 }; a4322e1881bed8 Wenhui Sheng 2020-08-11 115 :::::: The code at line 109 was first introduced by commit :::::: a4322e1881bed80ddb904482f0b2e948fa7fd47e drm/amdgpu: add debugfs interface for RAP test :::::: TO: Wenhui Sheng :::::: CC: Alex Deucher --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org