tree: https://github.com/0day-ci/linux/commits/UPDATE-20200221-182711/Peter-Zij... head: f4dfc8a95f29bf28eda9253734e8f6ffdc0c3d97 commit: 6d6e966e8cdfa647eb598e266414c176f6749010 [1/22] hardirq/nmi: Allow nested nmi_enter() config: powerpc-mpc8313_rdb_defconfig (attached as .config) compiler: powerpc-linux-gcc (GCC) 7.5.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross git checkout 6d6e966e8cdfa647eb598e266414c176f6749010 # save the attached .config to linux build tree GCC_VERSION=7.5.0 make.cross ARCH=powerpc If you fix the issue, kindly add following tag Reported-by: kbuild test robot <lkp(a)intel.com&gt; All errors (new ones prefixed by >>): arch/powerpc/kernel/traps.c: In function 'machine_check_exception': if (!nested) ^~~~~~ net arch/powerpc/kernel/traps.c:846:7: note: each undeclared identifier is reported only once for each function it appears in vim +846 arch/powerpc/kernel/traps.c 75918a4b5998c9 Olof Johansson 2007-09-21 815 75918a4b5998c9 Olof Johansson 2007-09-21 816 void machine_check_exception(struct pt_regs *regs) 75918a4b5998c9 Olof Johansson 2007-09-21 817 { 75918a4b5998c9 Olof Johansson 2007-09-21 818 int recover = 0; 6d6e966e8cdfa6 Peter Zijlstra 2020-02-19 819 b96672dd840f22 Nicholas Piggin 2017-07-19 820 nmi_enter(); 75918a4b5998c9 Olof Johansson 2007-09-21 821 69111bac42f5ce Christoph Lameter 2014-10-21 822 __this_cpu_inc(irq_stat.mce_exceptions); 89713ed1081540 Anton Blanchard 2010-01-31 823 d93b0ac01a9ce2 Mahesh Salgaonkar 2017-04-18 824 add_taint(TAINT_MACHINE_CHECK, LOCKDEP_NOW_UNRELIABLE); d93b0ac01a9ce2 Mahesh Salgaonkar 2017-04-18 825 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 826 /* See if any machine dependent calls. In theory, we would want 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 827 * to call the CPU first, and call the ppc_md. one if the CPU 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 828 * one returns a positive number. However there is existing code 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 829 * that assumes the board gets a first chance, so let's keep it 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 830 * that way for now and fix things later. --BenH. 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 831 */ 75918a4b5998c9 Olof Johansson 2007-09-21 832 if (ppc_md.machine_check_exception) 75918a4b5998c9 Olof Johansson 2007-09-21 833 recover = ppc_md.machine_check_exception(regs); 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 834 else if (cur_cpu_spec->machine_check) 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 835 recover = cur_cpu_spec->machine_check(regs); 75918a4b5998c9 Olof Johansson 2007-09-21 836 47c0bd1ae24c34 Benjamin Herrenschmidt 2007-12-21 837 if (recover > 0) ba12eedee321ee Li Zhong 2013-05-13 838 goto bail; 75918a4b5998c9 Olof Johansson 2007-09-21 839 a443506b8598bb Anton Blanchard 2011-01-11 840 if (debugger_fault_handler(regs)) ba12eedee321ee Li Zhong 2013-05-13 841 goto bail; 75918a4b5998c9 Olof Johansson 2007-09-21 842 75918a4b5998c9 Olof Johansson 2007-09-21 843 if (check_io_access(regs)) ba12eedee321ee Li Zhong 2013-05-13 844 goto bail; 75918a4b5998c9 Olof Johansson 2007-09-21 845 daf00ae71dad8a Christophe Leroy 2018-10-13 @846 if (!nested) daf00ae71dad8a Christophe Leroy 2018-10-13 847 nmi_exit(); daf00ae71dad8a Christophe Leroy 2018-10-13 848 daf00ae71dad8a Christophe Leroy 2018-10-13 849 die("Machine check", regs, SIGBUS); daf00ae71dad8a Christophe Leroy 2018-10-13 850 0bbea75c476b77 Christophe Leroy 2019-01-22 851 /* Must die if the interrupt is not recoverable */ 0bbea75c476b77 Christophe Leroy 2019-01-22 852 if (!(regs->msr & MSR_RI)) 0bbea75c476b77 Christophe Leroy 2019-01-22 853 nmi_panic(regs, "Unrecoverable Machine check"); 0bbea75c476b77 Christophe Leroy 2019-01-22 854 daf00ae71dad8a Christophe Leroy 2018-10-13 855 return; daf00ae71dad8a Christophe Leroy 2018-10-13 856 ba12eedee321ee Li Zhong 2013-05-13 857 bail: b96672dd840f22 Nicholas Piggin 2017-07-19 858 nmi_exit(); 14cf11af6cf608 Paul Mackerras 2005-09-26 859 } 14cf11af6cf608 Paul Mackerras 2005-09-26 860 :::::: The code at line 846 was first introduced by commit :::::: daf00ae71dad8aa05965713c62558aeebf2df48e powerpc/traps: restore recoverability of machine_check interrupts :::::: TO: Christophe Leroy <christophe.leroy(a)c-s.fr&gt; :::::: CC: Michael Ellerman <mpe(a)ellerman.id.au&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org