On Sun, Sep 06, 2020 at 05:14:15AM +0800, kernel test robot wrote:
tree: https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git char-misc-next
head: 99f667352f6c938440d9043d0f66f859d6f3d50d
commit: 99f667352f6c938440d9043d0f66f859d6f3d50d [28/28] /dev/zero: also implement ->read
config: m68k-randconfig-s031-20200904 (attached as .config)
compiler: m68k-linux-gcc (GCC) 9.3.0
Looks like m68 does not have proper __user annotations for clear_user..
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: v0.6.2-191-g10164920-dirty
git checkout 99f667352f6c938440d9043d0f66f859d6f3d50d
# 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=m68k
If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@xxxxxxxxx>
sparse warnings: (new ones prefixed by >>)
drivers/char/mem.c:163:37: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void *to @@ got char [noderef] __user *buf @@
drivers/char/mem.c:163:37: sparse: expected void *to
drivers/char/mem.c:163:37: sparse: got char [noderef] __user *buf
drivers/char/mem.c:737:21: sparse: sparse: incorrect type in argument 1 (different address spaces) @@ expected void *to @@ got char [noderef] __user * @@
drivers/char/mem.c:737:21: sparse: expected void *to
drivers/char/mem.c:737:21: sparse: got char [noderef] __user *
# https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git/commit/?id=99f667352f6c938440d9043d0f66f859d6f3d50d
git remote add char-misc https://git.kernel.org/pub/scm/linux/kernel/git/gregkh/char-misc.git
git fetch --no-tags char-misc char-misc-next
git checkout 99f667352f6c938440d9043d0f66f859d6f3d50d
vim +737 drivers/char/mem.c
728
729 static ssize_t read_zero(struct file *file, char __user *buf,
730 size_t count, loff_t *ppos)
731 {
732 size_t cleared = 0;
733
734 while (count) {
735 size_t chunk = min_t(size_t, count, PAGE_SIZE);
736
> 737 if (clear_user(buf + cleared, chunk))
738 return cleared ? cleared : -EFAULT;
739 cleared += chunk;
740 count -= chunk;
741
742 if (signal_pending(current))
743 return cleared ? cleared : -ERESTARTSYS;
744 cond_resched();
745 }
746
747 return cleared;
748 }
749
---
0-DAY CI Kernel Test Service, Intel Corporation
https://lists.01.org/hyperkitty/list/kbuild-all@xxxxxxxxxxxx
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