tree: https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git x86/fpu head: d52a4cb09008bb5ef97de5d64ab960063365c3b7 commit: 22553a4cfe428edf5b399552abc2ffd22918c4a9 [26/82] x86/fpu: Remove internal.h dependency from fpu/signal.h config: i386-buildonly-randconfig-r002-20211014 (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/tglx/devel.git/commit/?id=22553a4cfe428edf5b399552abc2ffd22918c4a9 git remote add tglx-devel https://git.kernel.org/pub/scm/linux/kernel/git/tglx/devel.git git fetch --no-tags tglx-devel x86/fpu git checkout 22553a4cfe428edf5b399552abc2ffd22918c4a9 # save the attached .config to linux build tree make W=1 ARCH=i386 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot All errors (new ones prefixed by >>): >> arch/x86/kernel/ptrace.c:1311:13: error: no previous prototype for 'update_regset_xstate_info' [-Werror=missing-prototypes] 1311 | void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) | ^~~~~~~~~~~~~~~~~~~~~~~~~ cc1: all warnings being treated as errors vim +/update_regset_xstate_info +1311 arch/x86/kernel/ptrace.c 5b3efd500854d4 Suresh Siddha 2010-02-11 1310 404f6aac9b3ef5 Kees Cook 2016-08-08 @1311 void __init update_regset_xstate_info(unsigned int size, u64 xstate_mask) 5b3efd500854d4 Suresh Siddha 2010-02-11 1312 { 5b3efd500854d4 Suresh Siddha 2010-02-11 1313 #ifdef CONFIG_X86_64 5b3efd500854d4 Suresh Siddha 2010-02-11 1314 x86_64_regsets[REGSET_XSTATE].n = size / sizeof(u64); 5b3efd500854d4 Suresh Siddha 2010-02-11 1315 #endif 5b3efd500854d4 Suresh Siddha 2010-02-11 1316 #if defined CONFIG_X86_32 || defined CONFIG_IA32_EMULATION 5b3efd500854d4 Suresh Siddha 2010-02-11 1317 x86_32_regsets[REGSET_XSTATE].n = size / sizeof(u64); 5b3efd500854d4 Suresh Siddha 2010-02-11 1318 #endif 5b3efd500854d4 Suresh Siddha 2010-02-11 1319 xstate_fx_sw_bytes[USER_XSTATE_XCR0_WORD] = xstate_mask; 5b3efd500854d4 Suresh Siddha 2010-02-11 1320 } 5b3efd500854d4 Suresh Siddha 2010-02-11 1321 :::::: The code at line 1311 was first introduced by commit :::::: 404f6aac9b3ef595735feca99979db084ea48315 x86: Apply more __ro_after_init and const :::::: TO: Kees Cook :::::: CC: Ingo Molnar --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org