tree: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux-stable-rc.git queue/5.7 head: 3bd920b35b8792c429a8d03bc264c16313f3bbd7 commit: 0974f9670e535cb9e66f3653c45d73607392b334 [181/371] riscv/atomic: Fix sign extension for RV64I config: riscv-randconfig-s032-20200707 (attached as .config) compiler: riscv32-linux-gcc (GCC) 9.3.0 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: v0.6.2-31-gabbfd661-dirty git checkout 0974f9670e535cb9e66f3653c45d73607392b334 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-9.3.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=riscv 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 >>) vim +40 net/mptcp/mib.c fc518953bc9c8d Florian Westphal 2020-03-27 27 fc518953bc9c8d Florian Westphal 2020-03-27 28 /* mptcp_mib_alloc - allocate percpu mib counters fc518953bc9c8d Florian Westphal 2020-03-27 29 * fc518953bc9c8d Florian Westphal 2020-03-27 30 * These are allocated when the first mptcp socket is created so fc518953bc9c8d Florian Westphal 2020-03-27 31 * we do not waste percpu memory if mptcp isn't in use. fc518953bc9c8d Florian Westphal 2020-03-27 32 */ fc518953bc9c8d Florian Westphal 2020-03-27 33 bool mptcp_mib_alloc(struct net *net) fc518953bc9c8d Florian Westphal 2020-03-27 34 { fc518953bc9c8d Florian Westphal 2020-03-27 35 struct mptcp_mib __percpu *mib = alloc_percpu(struct mptcp_mib); fc518953bc9c8d Florian Westphal 2020-03-27 36 fc518953bc9c8d Florian Westphal 2020-03-27 37 if (!mib) fc518953bc9c8d Florian Westphal 2020-03-27 38 return false; fc518953bc9c8d Florian Westphal 2020-03-27 39 fc518953bc9c8d Florian Westphal 2020-03-27 @40 if (cmpxchg(&net->mib.mptcp_statistics, NULL, mib)) fc518953bc9c8d Florian Westphal 2020-03-27 41 free_percpu(mib); fc518953bc9c8d Florian Westphal 2020-03-27 42 fc518953bc9c8d Florian Westphal 2020-03-27 43 return true; fc518953bc9c8d Florian Westphal 2020-03-27 44 } fc518953bc9c8d Florian Westphal 2020-03-27 45 :::::: The code at line 40 was first introduced by commit :::::: fc518953bc9c8d7d33c6ab261995f5038f3c87f9 mptcp: add and use MIB counter infrastructure :::::: TO: Florian Westphal <fw(a)strlen.de&gt; :::::: CC: David S. Miller <davem(a)davemloft.net&gt; --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org