tree: https://github.com/zen-kernel/zen-kernel 5.6/zen-sauce head: 28b9700a330bb5957c6ad7263095d148d5c35242 commit: 651fb09094936c829a4d430908c7e523e357cfbd [4/26] ZEN: Unrestrict CONFIG_OPTIMIZE_FOR_PERFORMANCE_O3 config: i386-randconfig-a005-20200521 (attached as .config) compiler: gcc-7 (Ubuntu 7.5.0-6ubuntu2) 7.5.0 reproduce: git checkout 651fb09094936c829a4d430908c7e523e357cfbd # save the attached .config to linux build tree make ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kbuild test robot <lkp(a)intel.com&gt; Note: it may well be a FALSE warning. FWIW you are at least aware of it now. All error/warnings (new ones prefixed by >>, old ones prefixed by <<): arch/x86/kvm/mmu/mmu.c: In function 'mmu_zap_unsync_children': struct kvm_mmu_page *sp = pvec->page[n].sp; ~~~~~~~~~~^~~ arch/x86/kvm/mmu/mmu.c:2383:28: error: array subscript is above array bounds [-Werror=array-bounds] unsigned idx = pvec->page[n].idx; ~~~~~~~~~~^~~ arch/x86/kvm/mmu/mmu.c: In function 'mmu_sync_children': struct kvm_mmu_page *sp = pvec->page[n].sp; ~~~~~~~~~~^~~ arch/x86/kvm/mmu/mmu.c:2383:28: error: array subscript is above array bounds [-Werror=array-bounds] unsigned idx = pvec->page[n].idx; ~~~~~~~~~~^~~ struct kvm_mmu_page *sp = pvec->page[n].sp; ~~~~~~~~~~^~~ arch/x86/kvm/mmu/mmu.c:2383:28: error: array subscript is above array bounds [-Werror=array-bounds] unsigned idx = pvec->page[n].idx; ~~~~~~~~~~^~~ cc1: all warnings being treated as errors -- drivers/base/devcon.c: In function 'device_connection_find': dev = bus_find_device_by_name(bus, NULL, con->endpoint[ep]); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ dev = bus_find_device_by_name(bus, NULL, con->endpoint[ep]); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ vim +2382 arch/x86/kvm/mmu/mmu.c 4731d4c7a07769c arch/x86/kvm/mmu.c Marcelo Tosatti 2008-09-23 2369 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2370 #define for_each_sp(pvec, sp, parents, i) \ 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2371 for (i = mmu_pages_first(&pvec, &parents); \ 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2372 i < pvec.nr && ({ sp = pvec.page[i].sp; 1;}); \ 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2373 i = mmu_pages_next(&pvec, &parents, i)) 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2374 cded19f396bc3c9 arch/x86/kvm/mmu.c Hannes Eder 2009-02-21 2375 static int mmu_pages_next(struct kvm_mmu_pages *pvec, cded19f396bc3c9 arch/x86/kvm/mmu.c Hannes Eder 2009-02-21 2376 struct mmu_page_path *parents, 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2377 int i) 4731d4c7a07769c arch/x86/kvm/mmu.c Marcelo Tosatti 2008-09-23 2378 { 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2379 int n; 4731d4c7a07769c arch/x86/kvm/mmu.c Marcelo Tosatti 2008-09-23 2380 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2381 for (n = i+1; n < pvec->nr; n++) { 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 @2382 struct kvm_mmu_page *sp = pvec->page[n].sp; 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2383 unsigned idx = pvec->page[n].idx; 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2384 int level = sp->role.level; 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2385 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2386 parents->idx[level-1] = idx; 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2387 if (level == PT_PAGE_TABLE_LEVEL) 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2388 break; 4731d4c7a07769c arch/x86/kvm/mmu.c Marcelo Tosatti 2008-09-23 2389 0a47cd85833e565 arch/x86/kvm/mmu.c Paolo Bonzini 2016-02-23 2390 parents->parent[level-2] = sp; 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2391 } 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2392 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2393 return n; 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2394 } 60c8aec6e2c9923 arch/x86/kvm/mmu.c Marcelo Tosatti 2008-12-01 2395 :::::: The code at line 2382 was first introduced by commit :::::: 60c8aec6e2c9923492dabbd6b67e34692bd26c20 KVM: MMU: use page array in unsync walk :::::: TO: Marcelo Tosatti <mtosatti(a)redhat.com&gt; :::::: CC: Avi Kivity <avi(a)redhat.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org