[kbuild-all] Re: [linux-next:master 1797/8629] drivers/tty/ipwireless/hardware.c:872:43: sparse: sparse: incorrect type in initializer (different base types)

On Thu, Sep 17, 2020 at 11:10 PM kernel test robot <lkp(a)intel.com&gt; wrote: > > tree: https://git.kernel.org/pub/scm/linux/kernel/git/next/linux-next.git master > head: 860461e4fcaa76200d2d1a53523e0ff7be92e6e8 > commit: 98c2922ec8f0601321428be8c59ae1df255478d1 [1797/8629] ARM: s3c24xx: simplify mach/io.h > config: arm-randconfig-s031-20200917 (attached as .config) > compiler: arm-linux-gnueabi-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: v0.6.2-201-g24bdaac6-dirty > git checkout 98c2922ec8f0601321428be8c59ae1df255478d1 > # 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=arm > > 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 >>) > > drivers/tty/ipwireless/hardware.c:431:25: sparse: sparse: cast from restricted __le16 > drivers/tty/ipwireless/hardware.c:445:25: sparse: sparse: cast from restricted __le16 > >> drivers/tty/ipwireless/hardware.c:872:43: sparse: sparse: incorrect type in initializer (different base types) @@ expected restricted __le16 [usertype] raw_data @@ got unsigned short [usertype] __v @@ > drivers/tty/ipwireless/hardware.c:872:43: sparse: expected restricted __le16 [usertype] raw_data > >> drivers/tty/ipwireless/hardware.c:872:43: sparse: got unsigned short [usertype] __v > drivers/tty/ipwireless/hardware.c:889:43: sparse: sparse: incorrect type in initializer (different base types) @@ expected restricted __le16 [usertype] raw_data @@ got unsigned short [usertype] __v @@ > drivers/tty/ipwireless/hardware.c:889:43: sparse: expected restricted __le16 [usertype] raw_data > drivers/tty/ipwireless/hardware.c:889:43: sparse: got unsigned short [usertype] __v I think it's a preexisting bug that we already get a warning for in other configurations, now the same warning also appears on s3c24xx. The bug was already in the original merge of the driver: + for (i = 0; i < len; i += 2) { + __le16 raw_data = inw(hw->base_port + IODMADPR); + unsigned short data = le16_to_cpu(raw_data); + + pkt[i] = (unsigned char) data; + pkt[i + 1] = (unsigned char) (data >> 8); + } This reimplements the insw() function with a total of three byte swaps on big-endian machines. I assume an even number of byte swaps (as done by inw) would have been needed to make it work on big-endian, but this depends on the actual hardware implementation. It seems unlikely that there are any big-endian machines with pc-card slots that would want to use this hardware.