Hi Kim, First bad commit (maybe != root cause): tree: https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git perf/core head: 0b8f94ea282357a79781d10024708c2cf0ff5305 commit: 10684f2b277c733c018c5d07ddb4aa980ba4fcc5 [7/8] perf/amd/uncore: Allow the driver to be built as a module config: i386-tinyconfig (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce (this is a W=1 build): # https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git/commit/?... git remote add peterz-queue https://git.kernel.org/pub/scm/linux/kernel/git/peterz/queue.git git fetch --no-tags peterz-queue perf/core git checkout 10684f2b277c733c018c5d07ddb4aa980ba4fcc5 # save the attached .config to linux build tree mkdir build_dir make W=1 O=build_dir ARCH=i386 SHELL=/bin/bash arch/x86/events/amd/ 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 >>): 829 | u32 get_ibs_caps(void) | ^~~~~~~~~~~~ In file included from include/linux/perf_event.h:25, from arch/x86/events/amd/ibs.c:9: arch/x86/include/asm/perf_event.h:426:19: note: previous definition of 'get_ibs_caps' was here 426 | static inline u32 get_ibs_caps(void) { return 0; } | ^~~~~~~~~~~~ arch/x86/events/amd/ibs.c: In function 'get_eilvt': 838 | return !setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 1); | ^~~~~~~~~~~~~~~~ cc1: some warnings being treated as errors vim +/get_ibs_caps +829 arch/x86/events/amd/ibs.c b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 828 b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 @829 u32 get_ibs_caps(void) b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 830 { b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 831 return ibs_caps; b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 832 } b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 833 b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 834 EXPORT_SYMBOL(get_ibs_caps); b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 835 b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 836 static inline int get_eilvt(int offset) b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 837 { b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 @838 return !setup_APIC_eilvt(offset, 0, APIC_EILVT_MSG_NMI, 1); b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 839 } b716916679e720 arch/x86/kernel/cpu/perf_event_amd_ibs.c Robert Richter 2011-09-21 840 :::::: The code at line 829 was first introduced by commit :::::: b716916679e72054d436afadce2f94dcad71cfad perf, x86: Implement IBS initialization :::::: TO: Robert Richter <robert.richter(a)amd.com&gt; :::::: CC: Ingo Molnar <mingo(a)elte.hu&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org