Hi Andy, I love your patch! Yet something to improve: [auto build test ERROR on net-next/master] url: https://github.com/0day-ci/linux/commits/Andy-Shevchenko/ptp_pch-use-mac_... base: https://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next.git b769cf44ed55f4b277b89cf53df6092f0c9082d0 config: powerpc64-randconfig-r034-20210813 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 62df4df41c939205b2dc0a2a3bfb75b8c1ed74fa) 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 powerpc64 cross compiling tool for clang build # apt-get install binutils-powerpc-linux-gnu # https://github.com/0day-ci/linux/commit/6c1fff5c80fe8f1a12c20bac2d28ebfa5... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review Andy-Shevchenko/ptp_pch-use-mac_pton/20210813-203135 git checkout 6c1fff5c80fe8f1a12c20bac2d28ebfa5960bde7 # save the attached .config to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross O=build_dir ARCH=powerpc SHELL=/bin/bash drivers/ptp/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All error/warnings (new ones prefixed by >>): __do_insb ^ arch/powerpc/include/asm/io.h:556:56: note: expanded from macro '__do_insb' #define __do_insb(p, b, n) readsb((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/ptp/ptp_pch.c:13: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:45:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insw, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:174:1: note: expanded from here __do_insw ^ arch/powerpc/include/asm/io.h:557:56: note: expanded from macro '__do_insw' #define __do_insw(p, b, n) readsw((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/ptp/ptp_pch.c:13: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:47:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(insl, (unsigned long p, void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:176:1: note: expanded from here __do_insl ^ arch/powerpc/include/asm/io.h:558:56: note: expanded from macro '__do_insl' #define __do_insl(p, b, n) readsl((PCI_IO_ADDR)_IO_BASE+(p), (b), (n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/ptp/ptp_pch.c:13: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:49:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsb, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:178:1: note: expanded from here __do_outsb ^ arch/powerpc/include/asm/io.h:559:58: note: expanded from macro '__do_outsb' #define __do_outsb(p, b, n) writesb((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/ptp/ptp_pch.c:13: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:51:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsw, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:180:1: note: expanded from here __do_outsw ^ arch/powerpc/include/asm/io.h:560:58: note: expanded from macro '__do_outsw' #define __do_outsw(p, b, n) writesw((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ In file included from drivers/ptp/ptp_pch.c:13: In file included from include/linux/interrupt.h:11: In file included from include/linux/hardirq.h:11: In file included from arch/powerpc/include/asm/hardirq.h:6: In file included from include/linux/irq.h:20: In file included from include/linux/io.h:13: In file included from arch/powerpc/include/asm/io.h:619: arch/powerpc/include/asm/io-defs.h:53:1: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] DEF_PCI_AC_NORET(outsl, (unsigned long p, const void *b, unsigned long c), ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/io.h:616:3: note: expanded from macro 'DEF_PCI_AC_NORET' __do_##name al; \ ^~~~~~~~~~~~~~ <scratch space>:182:1: note: expanded from here __do_outsl ^ arch/powerpc/include/asm/io.h:561:58: note: expanded from macro '__do_outsl' #define __do_outsl(p, b, n) writesl((PCI_IO_ADDR)_IO_BASE+(p),(b),(n)) ~~~~~~~~~~~~~~~~~~~~~^ module_pci_driver(pch_driver); ^ int module_pci_driver(pch_driver); ^ 13 warnings and 1 error generated. vim +604 drivers/ptp/ptp_pch.c 596 597 static struct pci_driver pch_driver = { 598 .name = KBUILD_MODNAME, 599 .id_table = pch_ieee1588_pcidev_id, 600 .probe = pch_probe, 601 .remove = pch_remove, 602 .driver.pm = &pch_pm_ops, 603 }; 605 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org