tree: https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git set_fs head: 0a081326831928b0d739bce68b8c0f9138b9c8ba commit: a954036380ae20dbfa0c203bf6cafb21d1f3cedd [6/11] uaccess: generalize access_ok() config: riscv-randconfig-s032-20220213 (https://download.01.org/0day-ci/archive/20220213/202202130419.oJqXwirc-lk...) compiler: riscv32-linux-gcc (GCC) 11.2.0 reproduce: wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # apt-get install sparse # sparse version: v0.6.4-dirty # https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git/commi... git remote add arnd-playground https://git.kernel.org/pub/scm/linux/kernel/git/arnd/playground.git git fetch --no-tags arnd-playground set_fs git checkout a954036380ae20dbfa0c203bf6cafb21d1f3cedd # save the config file to linux build tree mkdir build_dir COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-11.2.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=riscv SHELL=/bin/bash arch/riscv/kernel/ If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; sparse warnings: (new ones prefixed by >>) arch/riscv/kernel/perf_callchain.c:22:14: sparse: expected void const [noderef] __user *ptr arch/riscv/kernel/perf_callchain.c:22:14: sparse: got unsigned long *user_frame_tail arch/riscv/kernel/perf_callchain.c:24:49: sparse: sparse: incorrect type in argument 2 (different address spaces) @@ expected void const [noderef] __user *from @@ got unsigned long *user_frame_tail @@ arch/riscv/kernel/perf_callchain.c:24:49: sparse: expected void const [noderef] __user *from arch/riscv/kernel/perf_callchain.c:24:49: sparse: got unsigned long *user_frame_tail vim +22 arch/riscv/kernel/perf_callchain.c dbeb90b0c1eb86 Mao Han 2019-08-29 8 dbeb90b0c1eb86 Mao Han 2019-08-29 9 /* dbeb90b0c1eb86 Mao Han 2019-08-29 10 * Get the return address for a single stackframe and return a pointer to the dbeb90b0c1eb86 Mao Han 2019-08-29 11 * next frame tail. dbeb90b0c1eb86 Mao Han 2019-08-29 12 */ dbeb90b0c1eb86 Mao Han 2019-08-29 13 static unsigned long user_backtrace(struct perf_callchain_entry_ctx *entry, dbeb90b0c1eb86 Mao Han 2019-08-29 14 unsigned long fp, unsigned long reg_ra) dbeb90b0c1eb86 Mao Han 2019-08-29 15 { dbeb90b0c1eb86 Mao Han 2019-08-29 16 struct stackframe buftail; dbeb90b0c1eb86 Mao Han 2019-08-29 17 unsigned long ra = 0; dbeb90b0c1eb86 Mao Han 2019-08-29 18 unsigned long *user_frame_tail = dbeb90b0c1eb86 Mao Han 2019-08-29 19 (unsigned long *)(fp - sizeof(struct stackframe)); dbeb90b0c1eb86 Mao Han 2019-08-29 20 dbeb90b0c1eb86 Mao Han 2019-08-29 21 /* Check accessibility of one struct frame_tail beyond */ dbeb90b0c1eb86 Mao Han 2019-08-29 @22 if (!access_ok(user_frame_tail, sizeof(buftail))) dbeb90b0c1eb86 Mao Han 2019-08-29 23 return 0; dbeb90b0c1eb86 Mao Han 2019-08-29 24 if (__copy_from_user_inatomic(&buftail, user_frame_tail, dbeb90b0c1eb86 Mao Han 2019-08-29 25 sizeof(buftail))) dbeb90b0c1eb86 Mao Han 2019-08-29 26 return 0; dbeb90b0c1eb86 Mao Han 2019-08-29 27 dbeb90b0c1eb86 Mao Han 2019-08-29 28 if (reg_ra != 0) dbeb90b0c1eb86 Mao Han 2019-08-29 29 ra = reg_ra; dbeb90b0c1eb86 Mao Han 2019-08-29 30 else dbeb90b0c1eb86 Mao Han 2019-08-29 31 ra = buftail.ra; dbeb90b0c1eb86 Mao Han 2019-08-29 32 dbeb90b0c1eb86 Mao Han 2019-08-29 33 fp = buftail.fp; dbeb90b0c1eb86 Mao Han 2019-08-29 34 if (ra != 0) dbeb90b0c1eb86 Mao Han 2019-08-29 35 perf_callchain_store(entry, ra); dbeb90b0c1eb86 Mao Han 2019-08-29 36 else dbeb90b0c1eb86 Mao Han 2019-08-29 37 return 0; dbeb90b0c1eb86 Mao Han 2019-08-29 38 dbeb90b0c1eb86 Mao Han 2019-08-29 39 return fp; dbeb90b0c1eb86 Mao Han 2019-08-29 40 } dbeb90b0c1eb86 Mao Han 2019-08-29 41 :::::: The code at line 22 was first introduced by commit :::::: dbeb90b0c1eb86a9b963b929d3c937afb7dadfa3 riscv: Add perf callchain support :::::: TO: Mao Han <han_mao(a)c-sky.com&gt; :::::: CC: Paul Walmsley <paul.walmsley(a)sifive.com&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org