Hi brookxu, Thank you for the patch! Perhaps something to improve: [auto build test WARNING on linus/master] [also build test WARNING on v5.12-rc7 next-20210412] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch] url: https://github.com/0day-ci/linux/commits/brookxu/delayacct-refactor-the-c... base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git 89698becf06d341a700913c3d89ce2a914af69a2 config: x86_64-randconfig-s021-20210413 (attached as .config) compiler: gcc-9 (Debian 9.3.0-22) 9.3.0 reproduce: # apt-get install sparse # sparse version: v0.6.3-280-g2cd6d34e-dirty # https://github.com/0day-ci/linux/commit/7023a409dec95195a0e3360a36e8cb663... git remote add linux-review https://github.com/0day-ci/linux git fetch --no-tags linux-review brookxu/delayacct-refactor-the-code-to-simplify-the-implementation/20210413-093934 git checkout 7023a409dec95195a0e3360a36e8cb66363a9457 # save the attached .config to linux build tree make W=1 C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' ARCH=x86_64 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 >>) Please review and possibly fold the followup patch. --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org