[kbuild-all] drivers/gpio/gpio-virtio.c:23:8: warning: Excessive padding in 'struct virtio_gpio_line' (122 padding bytes, where 58 is optimal).

tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master head: 78e709522d2c012cb0daad2e668506637bffb7c2 commit: 3a29355a22c0275fe864100794fee58a73175d93 gpio: Add virtio-gpio driver date: 3 weeks ago :::::: branch date: 19 hours ago :::::: commit date: 3 weeks ago config: x86_64-randconfig-c007-20210911 (attached as .config) compiler: clang version 14.0.0 (https://github.com/llvm/llvm-project 261cbe98c38f8c1ee1a482fe76511110e790f58a) 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/torvalds/linux.git/commit... git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git git fetch --no-tags linus master git checkout 3a29355a22c0275fe864100794fee58a73175d93 # save the attached .config to linux build tree COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross ARCH=x86_64 clang-analyzer If you fix the issue, kindly add following tag as appropriate Reported-by: kernel test robot <lkp(a)intel.com&gt; clang-analyzer warnings: (new ones prefixed by >>) Optimal fields order: res, rxlen, completion, lock, req, consider reordering the fields or adding explicit padding members [clang-analyzer-optin.performance.Padding] vim +23 drivers/gpio/gpio-virtio.c 3a29355a22c027 Viresh Kumar 2021-08-19 22 3a29355a22c027 Viresh Kumar 2021-08-19 @23 struct virtio_gpio_line { 3a29355a22c027 Viresh Kumar 2021-08-19 24 struct mutex lock; /* Protects line operation */ 3a29355a22c027 Viresh Kumar 2021-08-19 25 struct completion completion; 3a29355a22c027 Viresh Kumar 2021-08-19 26 struct virtio_gpio_request req ____cacheline_aligned; 3a29355a22c027 Viresh Kumar 2021-08-19 27 struct virtio_gpio_response res ____cacheline_aligned; 3a29355a22c027 Viresh Kumar 2021-08-19 28 unsigned int rxlen; 3a29355a22c027 Viresh Kumar 2021-08-19 29 }; 3a29355a22c027 Viresh Kumar 2021-08-19 30 --- 0-DAY CI Kernel Test Service, Intel Corporation https://lists.01.org/hyperkitty/list/kbuild-all@lists.01.org