Hi Badhri, kernel test robot noticed the following build warnings: [auto build test WARNING on d37537a1f7cf09e304fe7993cb5e732534a0fb22] url: https://github.com/intel-lab-lkp/linux/commits/Badhri-Jagan-Sridharan/usb-gadget-udc-core-Prevent-soft_connect_store-race/20230609-044555 base: d37537a1f7cf09e304fe7993cb5e732534a0fb22 patch link: https://lore.kernel.org/r/20230608204517.105396-2-badhri%40google.com patch subject: [PATCH v7 2/2] usb: gadget: udc: core: Prevent soft_connect_store() race config: hexagon-randconfig-r015-20230608 (https://download.01.org/0day-ci/archive/20230609/202306090722.opxFRfOO-lkp@xxxxxxxxx/config) compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project.git 4a5ac14ee968ff0ad5d2cc1ffa0299048db4c88a) reproduce (this is a W=1 build): mkdir -p ~/bin wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout d37537a1f7cf09e304fe7993cb5e732534a0fb22 b4 shazam https://lore.kernel.org/r/20230608204517.105396-2-badhri@xxxxxxxxxx # save the config file mkdir build_dir && cp config build_dir/.config COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=hexagon olddefconfig COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang ~/bin/make.cross W=1 O=build_dir ARCH=hexagon SHELL=/bin/bash drivers/usb/gadget/udc/ If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot <lkp@xxxxxxxxx> | Closes: https://lore.kernel.org/oe-kbuild-all/202306090722.opxFRfOO-lkp@xxxxxxxxx/ All warnings (new ones prefixed by >>): In file included from drivers/usb/gadget/udc/core.c:17: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:547:31: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 547 | val = __raw_readb(PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:560:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 560 | val = __le16_to_cpu((__le16 __force)__raw_readw(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:37:51: note: expanded from macro '__le16_to_cpu' 37 | #define __le16_to_cpu(x) ((__force __u16)(__le16)(x)) | ^ In file included from drivers/usb/gadget/udc/core.c:17: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:573:61: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 573 | val = __le32_to_cpu((__le32 __force)__raw_readl(PCI_IOBASE + addr)); | ~~~~~~~~~~ ^ include/uapi/linux/byteorder/little_endian.h:35:51: note: expanded from macro '__le32_to_cpu' 35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x)) | ^ In file included from drivers/usb/gadget/udc/core.c:17: In file included from include/linux/dma-mapping.h:10: In file included from include/linux/scatterlist.h:9: In file included from arch/hexagon/include/asm/io.h:334: include/asm-generic/io.h:584:33: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 584 | __raw_writeb(value, PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:594:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 594 | __raw_writew((u16 __force)cpu_to_le16(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ include/asm-generic/io.h:604:59: warning: performing pointer arithmetic on a null pointer has undefined behavior [-Wnull-pointer-arithmetic] 604 | __raw_writel((u32 __force)cpu_to_le32(value), PCI_IOBASE + addr); | ~~~~~~~~~~ ^ >> drivers/usb/gadget/udc/core.c:850:1: warning: unused label 'out' [-Wunused-label] 850 | out: | ^~~~ 851 | trace_usb_gadget_deactivate(gadget, ret); drivers/usb/gadget/udc/core.c:886:1: warning: unused label 'out' [-Wunused-label] 886 | out: | ^~~~ 887 | trace_usb_gadget_activate(gadget, ret); 8 warnings generated. vim +/out +850 drivers/usb/gadget/udc/core.c 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 815 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 816 /** 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 817 * usb_gadget_deactivate - deactivate function which is not ready to work 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 818 * @gadget: the peripheral being deactivated 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 819 * 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 820 * This routine may be used during the gadget driver bind() call to prevent 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 821 * the peripheral from ever being visible to the USB host, unless later 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 822 * usb_gadget_activate() is called. For example, user mode components may 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 823 * need to be activated before the system can talk to hosts. 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 824 * 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 825 * Returns zero on success, else negative errno. 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 826 */ 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 827 int usb_gadget_deactivate(struct usb_gadget *gadget) 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 828 { 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 829 int ret = 0; 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 830 bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 831 mutex_lock(&gadget->udc->connect_lock); 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 832 if (gadget->deactivated) bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 833 goto unlock; 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 834 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 835 if (gadget->connected) { bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 836 ret = usb_gadget_disconnect_locked(gadget); 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 837 if (ret) bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 838 goto unlock; 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 839 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 840 /* 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 841 * If gadget was being connected before deactivation, we want 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 842 * to reconnect it in usb_gadget_activate(). 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 843 */ 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 844 gadget->connected = true; 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 845 } 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 846 gadget->deactivated = true; 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 847 bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 848 unlock: bfc8a68e3289a9 drivers/usb/gadget/udc/core.c Badhri Jagan Sridharan 2023-06-08 849 mutex_unlock(&gadget->udc->connect_lock); 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 @850 out: 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 851 trace_usb_gadget_deactivate(gadget, ret); 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 852 5e42d710a108c2 drivers/usb/gadget/udc/core.c Felipe Balbi 2016-05-31 853 return ret; 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 854 } 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 855 EXPORT_SYMBOL_GPL(usb_gadget_deactivate); 5a8d651a2bde01 drivers/usb/gadget/udc/udc-core.c Felipe Balbi 2016-05-31 856 -- 0-DAY CI Kernel Test Service https://github.com/intel/lkp-tests/wiki