Hi Prabhat, FYI, the error/warning still remains. tree: https://github.com/intel/linux-intel-lts.git 4.19/android_r head: 71dbe8b787e34f3ce300217fc6ca5a2ec4aef447 commit: b88d999a5b9ae9022e12e1a5810b12b21cb77996 [18600/23451] usb: xhci: dbc: make DbC modular, introducing dbc_function structure config: h8300-randconfig-r031-20210622 (attached as .config) compiler: h8300-linux-gcc (GCC) 9.3.0 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 # https://github.com/intel/linux-intel-lts/commit/b88d999a5b9ae9022e12e1a58... git remote add intel-linux-intel-lts https://github.com/intel/linux-intel-lts.git git fetch --no-tags intel-linux-intel-lts 4.19/android_r git checkout b88d999a5b9ae9022e12e1a5810b12b21cb77996 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=h8300 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All warnings (new ones prefixed by >>): In file included from include/linux/string.h:6, from include/linux/dma-mapping.h:6, from drivers/usb/host/xhci-dbgcap.c:9: include/linux/scatterlist.h: In function 'sg_set_buf': include/asm-generic/page.h:93:50: warning: ordered comparison of pointer with null pointer [-Wextra] 93 | #define virt_addr_valid(kaddr) (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \ | ^~ include/linux/compiler.h:77:42: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/scatterlist.h:143:2: note: in expansion of macro 'BUG_ON' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~ include/linux/scatterlist.h:143:10: note: in expansion of macro 'virt_addr_valid' 143 | BUG_ON(!virt_addr_valid(buf)); | ^~~~~~~~~~~~~~~ include/linux/dma-mapping.h: In function 'dma_map_resource': include/asm-generic/page.h:91:32: warning: comparison of unsigned expression >= 0 is always true [-Wtype-limits] 91 | #define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr) | ^~ include/linux/compiler.h:77:42: note: in definition of macro 'unlikely' 77 | # define unlikely(x) __builtin_expect(!!(x), 0) | ^ include/linux/dma-mapping.h:329:2: note: in expansion of macro 'BUG_ON' 329 | BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); | ^~~~~~ include/linux/dma-mapping.h:329:9: note: in expansion of macro 'pfn_valid' 329 | BUG_ON(pfn_valid(PHYS_PFN(phys_addr))); | ^~~~~~~~~ drivers/usb/host/xhci-dbgcap.c: In function 'xhci_dbc_populate_strings': drivers/usb/host/xhci-dbgcap.c:50:36: warning: taking address of packed member of 'struct usb_string_descriptor' may result in an unaligned pointer value [-Waddress-of-packed-member] 50 | UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, | ^~~~~~ drivers/usb/host/xhci-dbgcap.c:61:36: warning: taking address of packed member of 'struct usb_string_descriptor' may result in an unaligned pointer value [-Waddress-of-packed-member] 61 | UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, | ^~~~~~ drivers/usb/host/xhci-dbgcap.c:73:36: warning: taking address of packed member of 'struct usb_string_descriptor' may result in an unaligned pointer value [-Waddress-of-packed-member] 73 | UTF16_LITTLE_ENDIAN, (wchar_t *)s_desc->wData, | ^~~~~~ drivers/usb/host/xhci-dbgcap.c: At top level: 191 | void xhci_dbc_flush_requests(struct xhci_dbc *dbc) | ^~~~~~~~~~~~~~~~~~~~~~~ drivers/usb/host/xhci-dbgcap.c: In function 'xhci_dbc_handle_events': drivers/usb/host/xhci-dbgcap.c:794:8: warning: variable 'ret' set but not used [-Wunused-but-set-variable] 794 | int ret; | ^~~ drivers/usb/host/xhci-dbgcap.c:18: warning: cannot understand function prototype: 'struct dbc_function *dbc_registered_func; ' vim +/xhci_dbc_flush_requests +191 drivers/usb/host/xhci-dbgcap.c 189 190 192 { 193 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_OUT]); 194 xhci_dbc_flush_endpoint_requests(&dbc->eps[BULK_IN]); 195 } 196 EXPORT_SYMBOL_GPL(xhci_dbc_flush_requests); 197 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org