drivers/net/ethernet/sfc/siena/selftest.c:46:15: warning: field ip within 'struct efx_loopback_payload' is less aligned than 'struct iphdr' and is usually due to 'struct efx_loopback_payload' being packed, which can lead to unaligned accesses

[kernel test robot <lkp@intel.com>]

Hi Martin,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   e35e5b6f695d241ffb1d223207da58a1fbcdff4b
commit: c5a13c319e10e795850b61bc7e3447b08024be2e sfc: Add a basic Siena module
date:   8 weeks ago
config: arm-randconfig-r004-20220706 (https://download.01.org/0day-ci/archive/20220706/202207062332.BG1QJUUo-lkp@intel.com/config)
compiler: clang version 15.0.0 (https://github.com/llvm/llvm-project f553287b588916de09c66e3e32bf75e5060f967f)
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
        # install arm cross compiling tool for clang build
        # apt-get install binutils-arm-linux-gnueabi
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=c5a13c319e10e795850b61bc7e3447b08024be2e
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout c5a13c319e10e795850b61bc7e3447b08024be2e
        # save the config file
        mkdir build_dir && cp config build_dir/.config
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm SHELL=/bin/bash drivers/net/ethernet/sfc/siena/

If you fix the issue, kindly add following tag where applicable
Reported-by: kernel test robot <lkp@intel.com>

All warnings (new ones prefixed by >>):

>> drivers/net/ethernet/sfc/siena/selftest.c:46:15: warning: field ip within 'struct efx_loopback_payload' is less aligned than 'struct iphdr' and is usually due to 'struct efx_loopback_payload' being packed, which can lead to unaligned accesses [-Wunaligned-access]
           struct iphdr ip;
                        ^
   1 warning generated.


vim +46 drivers/net/ethernet/sfc/siena/selftest.c

d48523cb88e0703 Martin Habets 2022-05-09  37  
d48523cb88e0703 Martin Habets 2022-05-09  38  /*
d48523cb88e0703 Martin Habets 2022-05-09  39   * Loopback test packet structure
d48523cb88e0703 Martin Habets 2022-05-09  40   *
d48523cb88e0703 Martin Habets 2022-05-09  41   * The self-test should stress every RSS vector, and unfortunately
d48523cb88e0703 Martin Habets 2022-05-09  42   * Falcon only performs RSS on TCP/UDP packets.
d48523cb88e0703 Martin Habets 2022-05-09  43   */
d48523cb88e0703 Martin Habets 2022-05-09  44  struct efx_loopback_payload {
d48523cb88e0703 Martin Habets 2022-05-09  45  	struct ethhdr header;
d48523cb88e0703 Martin Habets 2022-05-09 @46  	struct iphdr ip;
d48523cb88e0703 Martin Habets 2022-05-09  47  	struct udphdr udp;
d48523cb88e0703 Martin Habets 2022-05-09  48  	__be16 iteration;
d48523cb88e0703 Martin Habets 2022-05-09  49  	char msg[64];
d48523cb88e0703 Martin Habets 2022-05-09  50  } __packed;
d48523cb88e0703 Martin Habets 2022-05-09  51  

:::::: The code at line 46 was first introduced by commit
:::::: d48523cb88e0703055c1b33e61eb644a7976f92b sfc: Copy shared files needed for Siena (part 2)

:::::: TO: Martin Habets <martinh@xilinx.com>
:::::: CC: Jakub Kicinski <kuba@kernel.org>

-- 
0-DAY CI Kernel Test Service
https://01.org/lkp