Hi Krzysztof, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: b791d1bdf9212d944d749a5c7ff6febdba241771 commit: 88eaaecc44461f9fb147bf7ee6ccc6d4e9fc23e0 usb: host: Enable compile testing for some of drivers date: 6 months ago config: h8300-randconfig-r024-20200612 (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 git checkout 88eaaecc44461f9fb147bf7ee6ccc6d4e9fc23e0 # 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 >>, old ones prefixed by <<): In file included from arch/h8300/include/asm/bug.h:8, from include/linux/bug.h:5, from include/linux/thread_info.h:12, from include/asm-generic/current.h:5, from ./arch/h8300/include/generated/asm/current.h:1, from include/linux/mutex.h:14, from include/linux/notifier.h:14, from include/linux/clk.h:14, from drivers/usb/host/ohci-at91.c:16: 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/asm-generic/bug.h:139:27: note: in definition of macro 'WARN_ON_ONCE' 139 | int __ret_warn_once = !!(condition); | ^~~~~~~~~ include/linux/dma-mapping.h:352:19: note: in expansion of macro 'pfn_valid' 352 | if (WARN_ON_ONCE(pfn_valid(PHYS_PFN(phys_addr)))) | ^~~~~~~~~ drivers/usb/host/ohci-at91.c: In function 'ohci_at91_hub_control': 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ 347 | if (valid_port(wIndex)) { | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:356:8: note: in expansion of macro 'valid_port' 356 | if (valid_port(wIndex) && ohci_at91->sfr_regmap) { | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:371:8: note: in expansion of macro 'valid_port' 371 | if (valid_port(wIndex)) { | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:382:8: note: in expansion of macro 'valid_port' 382 | if (valid_port(wIndex)) | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:391:8: note: in expansion of macro 'valid_port' 391 | if (valid_port(wIndex)) { | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:399:8: note: in expansion of macro 'valid_port' 399 | if (valid_port(wIndex) && ohci_at91->sfr_regmap) { | ^~~~~~~~~~ 33 | #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) | ^~ drivers/usb/host/ohci-at91.c:447:7: note: in expansion of macro 'valid_port' 447 | if (valid_port(wIndex)) { | ^~~~~~~~~~ In file included from drivers/usb/host/ohci-at91.c:31: At top level: drivers/usb/host/ohci.h:165:18: warning: 'cc_to_error' defined but not used [-Wunused-const-variable=] 165 | static const int cc_to_error [16] = { | ^~~~~~~~~~~ vim +33 drivers/usb/host/ohci-at91.c 39a269c09f854d Andrew Victor 2006-01-22 32 0ee6d1eeef7bf4 Nicolas Ferre 2012-03-21 @33 #define valid_port(index) ((index) >= 0 && (index) < AT91_MAX_USBH_PORTS) 0ee6d1eeef7bf4 Nicolas Ferre 2012-03-21 34 #define at91_for_each_port(index) \ 0ee6d1eeef7bf4 Nicolas Ferre 2012-03-21 35 for ((index) = 0; (index) < AT91_MAX_USBH_PORTS; (index)++) 0ee6d1eeef7bf4 Nicolas Ferre 2012-03-21 36 :::::: The code at line 33 was first introduced by commit :::::: 0ee6d1eeef7bf4e08aba37bf1da377b25e8d853a USB: ohci-at91: change maximum number of ports :::::: TO: Nicolas Ferre <nicolas.ferre(a)atmel.com&gt; :::::: CC: Nicolas Ferre <nicolas.ferre(a)atmel.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org