Hi Arnd, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git ixp4 head: e0bf0c1bc94b9100d85ace594fd1f0fb0024dbf2 commit: f98dec27333d7a6d39cfafb90e3305b491bf7c4a [7/14] watchdog: ixp4xx: move mmio access to timer driver config: mips-allyesconfig (attached as .config) compiler: mips-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://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git/... git remote add nomadik https://git.kernel.org/pub/scm/linux/kernel/git/linusw/linux-nomadik.git git fetch --no-tags nomadik ixp4 git checkout f98dec27333d7a6d39cfafb90e3305b491bf7c4a # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross W=1 ARCH=mips If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): drivers/watchdog/ixp4xx_wdt.c: In function 'ixp4xx_wdt_init': 175 | if (!(read_cpuid_id() & 0xf) && !cpu_is_ixp46x()) { | ^~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +/read_cpuid_id +175 drivers/watchdog/ixp4xx_wdt.c ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 164 ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 165 static int __init ixp4xx_wdt_init(void) ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 166 { ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 167 int ret; ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 168 f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 169 ret = ixp4xx_boot_status(); f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 170 if (ret < 0) f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 171 return ret; f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 172 f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 173 boot_status = ret ? WDIOF_CARDRESET : 0; f98dec27333d7a drivers/watchdog/ixp4xx_wdt.c Arnd Bergmann 2019-08-26 174 0ba8b9b273c45d drivers/watchdog/ixp4xx_wdt.c Russell King 2008-08-10 @175 if (!(read_cpuid_id() & 0xf) && !cpu_is_ixp46x()) { 27c766aaacb265 drivers/watchdog/ixp4xx_wdt.c Joe Perches 2012-02-15 176 pr_err("Rev. A0 IXP42x CPU detected - watchdog disabled\n"); ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 177 ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 178 return -ENODEV; ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 179 } ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 180 ret = misc_register(&ixp4xx_wdt_miscdev); ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 181 if (ret == 0) 27c766aaacb265 drivers/watchdog/ixp4xx_wdt.c Joe Perches 2012-02-15 182 pr_info("timer heartbeat %d sec\n", heartbeat); ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 183 return ret; ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 184 } ^1da177e4c3f41 drivers/char/watchdog/ixp4xx_wdt.c Linus Torvalds 2005-04-16 185 :::::: The code at line 175 was first introduced by commit :::::: 0ba8b9b273c45dd23f60ff700e265a0069b33758 [ARM] cputype: separate definitions, use them :::::: TO: Russell King <rmk(a)dyn-67.arm.linux.org.uk&gt; :::::: CC: Russell King <rmk+kernel(a)arm.linux.org.uk&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org