Hello Miquel, A situation noted by the warning below won't cause any problem because the casting is done to a non-dereferenced variable. It is utilized as a pointer bias later in that function. Shall we just ignore the warning or still fix it somehow?
-Sergey On Mon, Nov 02, 2020 at 12:42:57PM +0800, kernel test robot wrote: > tree: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > master > head: 3cea11cd5e3b00d91caf0b4730194039b45c5891 > commit: b3e79e7682e075326df8041b826b03453acacd0a mtd: physmap: Add Baikal-T1 > physically mapped ROM support > date: 4 weeks ago > config: sparc64-randconfig-s032-20201031 (attached as .config) > compiler: sparc64-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: v0.6.3-76-gf680124b-dirty > # > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b3e79e7682e075326df8041b826b03453acacd0a > git remote add linus > https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git > git fetch --no-tags linus master > git checkout b3e79e7682e075326df8041b826b03453acacd0a > # 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=sparc64 > > If you fix the issue, kindly add following tag as appropriate > Reported-by: kernel test robot <l...@intel.com> > > > "sparse warnings: (new ones prefixed by >>)" > >> drivers/mtd/maps/physmap-bt1-rom.c:78:18: sparse: sparse: cast removes > >> address space '__iomem' of expression > > vim +/__iomem +78 drivers/mtd/maps/physmap-bt1-rom.c > > 57 > 58 static void __xipram bt1_rom_map_copy_from(struct map_info *map, > 59 void *to, unsigned > long from, > 60 ssize_t len) > 61 { > 62 void __iomem *src = map->virt + from; > 63 ssize_t shift, chunk; > 64 u32 data; > 65 > 66 if (len <= 0 || from >= map->size) > 67 return; > 68 > 69 /* Make sure we don't go over the map limit. */ > 70 len = min_t(ssize_t, map->size - from, len); > 71 > 72 /* > 73 * Since requested data size can be pretty big we have > to implement > 74 * the copy procedure as optimal as possible. That's > why it's split > 75 * up into the next three stages: unaligned head, > aligned body, > 76 * unaligned tail. > 77 */ > > 78 shift = (ssize_t)src & 0x3; > 79 if (shift) { > 80 chunk = min_t(ssize_t, 4 - shift, len); > 81 data = readl_relaxed(src - shift); > 82 memcpy(to, &data + shift, chunk); > 83 src += chunk; > 84 to += chunk; > 85 len -= chunk; > 86 } > 87 > 88 while (len >= 4) { > 89 data = readl_relaxed(src); > 90 memcpy(to, &data, 4); > 91 src += 4; > 92 to += 4; > 93 len -= 4; > 94 } > 95 > 96 if (len) { > 97 data = readl_relaxed(src); > 98 memcpy(to, &data, len); > 99 } > 100 } > 101 > > --- > 0-DAY CI Kernel Test Service, Intel Corporation > https://lists.01.org/hyperkitty/list/kbuild-...@lists.01.org
