tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git linux-4.19.y head: 54354bc5e2a599518c25769b56d76eabe94e67c9 commit: 31ebc2fe02df202566d0e36c1106b4902d6e2f8c [2158/3140] powerpc/64s: flush L1D after user accesses config: powerpc64-randconfig-r032-20210209 (attached as .config) compiler: powerpc64le-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/stable/linux-stable-rc.gi... git remote add linux-stable-rc https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git git fetch --no-tags linux-stable-rc linux-4.19.y git checkout 31ebc2fe02df202566d0e36c1106b4902d6e2f8c # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross ARCH=powerpc64 If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; All error/warnings (new ones prefixed by >>): In file included from arch/powerpc/include/asm/book3s/64/mmu-hash.h:24, from arch/powerpc/include/asm/book3s/64/mmu.h:30, from arch/powerpc/include/asm/mmu.h:313, from arch/powerpc/include/asm/lppaca.h:36, from arch/powerpc/include/asm/paca.h:21, from arch/powerpc/include/asm/hw_irq.h:64, from arch/powerpc/include/asm/irqflags.h:12, from include/linux/irqflags.h:16, from include/linux/spinlock.h:54, from include/linux/seqlock.h:36, from include/linux/time.h:6, from include/linux/stat.h:19, from include/linux/compat.h:12, from arch/powerpc/kernel/asm-offsets.c:16: arch/powerpc/include/asm/book3s/64/pgtable.h:1292:15: warning: type qualifiers ignored on function return type [-Wignored-qualifiers] 1292 | static inline const int pud_pfn(pud_t pud) | ^~~~~ In file included from arch/powerpc/include/asm/kup.h:10, from arch/powerpc/include/asm/uaccess.h:9, from include/linux/uaccess.h:14, from include/linux/compat.h:19, from arch/powerpc/kernel/asm-offsets.c:16: 5 | DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); | ^~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/book3s/64/kup-radix.h: In function 'prevent_user_access': 18 | if (static_branch_unlikely(&uaccess_flush_key)) | ^~~~~~~~~~~~~~~~~~~~~~ 18 | if (static_branch_unlikely(&uaccess_flush_key)) | ^~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/book3s/64/kup-radix.h:18:30: note: each undeclared identifier is reported only once for each function it appears in cc1: some warnings being treated as errors -- In file included from arch/powerpc/include/asm/book3s/64/mmu-hash.h:24, from arch/powerpc/include/asm/book3s/64/mmu.h:30, from arch/powerpc/include/asm/mmu.h:313, from arch/powerpc/include/asm/lppaca.h:36, from arch/powerpc/include/asm/paca.h:21, from arch/powerpc/include/asm/hw_irq.h:64, from arch/powerpc/include/asm/irqflags.h:12, from include/linux/irqflags.h:16, from include/linux/spinlock.h:54, from include/linux/seqlock.h:36, from include/linux/time.h:6, from include/linux/stat.h:19, from include/linux/compat.h:12, from arch/powerpc/kernel/asm-offsets.c:16: arch/powerpc/include/asm/book3s/64/pgtable.h:1292:15: warning: type qualifiers ignored on function return type [-Wignored-qualifiers] 1292 | static inline const int pud_pfn(pud_t pud) | ^~~~~ In file included from arch/powerpc/include/asm/kup.h:10, from arch/powerpc/include/asm/uaccess.h:9, from include/linux/uaccess.h:14, from include/linux/compat.h:19, from arch/powerpc/kernel/asm-offsets.c:16: 5 | DECLARE_STATIC_KEY_FALSE(uaccess_flush_key); | ^~~~~~~~~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/book3s/64/kup-radix.h: In function 'prevent_user_access': 18 | if (static_branch_unlikely(&uaccess_flush_key)) | ^~~~~~~~~~~~~~~~~~~~~~ 18 | if (static_branch_unlikely(&uaccess_flush_key)) | ^~~~~~~~~~~~~~~~~ arch/powerpc/include/asm/book3s/64/kup-radix.h:18:30: note: each undeclared identifier is reported only once for each function it appears in cc1: some warnings being treated as errors make[2]: *** [./Kbuild:56: arch/powerpc/kernel/asm-offsets.s] Error 1 make[2]: Target '__build' not remade because of errors. make[1]: *** [Makefile:1123: prepare0] Error 2 make[1]: Target 'prepare' not remade because of errors. make: *** [Makefile:146: sub-make] Error 2 make: Target 'prepare' not remade because of errors. vim +5 arch/powerpc/include/asm/book3s/64/kup-radix.h 4 6 7 /* Prototype for function defined in exceptions-64s.S */ 8 void do_uaccess_flush(void); 9 10 static __always_inline void allow_user_access(void __user *to, const void __user *from, 11 unsigned long size) 12 { 13 } 14 15 static inline void prevent_user_access(void __user *to, const void __user *from, 16 unsigned long size) 17 { 19 do_uaccess_flush(); 20 } 21 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org