Re: [PATCH 23/32] iov_iter: copy_folio_from_iter_atomic()

From: kernel test robot
Date: Wed May 10 2023 - 22:08:59 EST


Hi Kent,

kernel test robot noticed the following build warnings:

[auto build test WARNING on tip/locking/core]
[cannot apply to axboe-block/for-next akpm-mm/mm-everything kdave/for-next linus/master v6.4-rc1 next-20230510]
[If your patch is applied to the wrong git tree, kindly drop us a note.
And when submitting patch, we suggest to use '--base' as documented in
https://git-scm.com/docs/git-format-patch#_base_tree_information]

url: https://github.com/intel-lab-lkp/linux/commits/Kent-Overstreet/Compiler-Attributes-add-__flatten/20230510-010302
base: tip/locking/core
patch link: https://lore.kernel.org/r/20230509165657.1735798-24-kent.overstreet%40linux.dev
patch subject: [PATCH 23/32] iov_iter: copy_folio_from_iter_atomic()
config: powerpc-randconfig-s042-20230509 (https://download.01.org/0day-ci/archive/20230511/202305110949.RCcHYzkJ-lkp@xxxxxxxxx/config)
compiler: powerpc-linux-gcc (GCC) 12.1.0
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: v0.6.4-39-gce1a6720-dirty
# https://github.com/intel-lab-lkp/linux/commit/0e5d4229f5e7671dabba56ea36583b1ca20a9a18
git remote add linux-review https://github.com/intel-lab-lkp/linux
git fetch --no-tags linux-review Kent-Overstreet/Compiler-Attributes-add-__flatten/20230510-010302
git checkout 0e5d4229f5e7671dabba56ea36583b1ca20a9a18
# save the config file
mkdir build_dir && cp config build_dir/.config
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=powerpc olddefconfig
COMPILER_INSTALL_PATH=$HOME/0day COMPILER=gcc-12.1.0 make.cross C=1 CF='-fdiagnostic-prefix -D__CHECK_ENDIAN__' O=build_dir ARCH=powerpc SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@xxxxxxxxx>
| Link: https://lore.kernel.org/oe-kbuild-all/202305110949.RCcHYzkJ-lkp@xxxxxxxxx/

sparse warnings: (new ones prefixed by >>)
>> lib/iov_iter.c:839:30: sparse: sparse: incompatible types in comparison expression (different type sizes):
>> lib/iov_iter.c:839:30: sparse: unsigned int *
>> lib/iov_iter.c:839:30: sparse: unsigned long *

vim +839 lib/iov_iter.c

825
826 size_t copy_folio_from_iter_atomic(struct folio *folio, size_t offset,
827 size_t bytes, struct iov_iter *i)
828 {
829 size_t ret = 0;
830
831 if (WARN_ON(offset + bytes > folio_size(folio)))
832 return 0;
833 if (WARN_ON_ONCE(!i->data_source))
834 return 0;
835
836 #ifdef CONFIG_HIGHMEM
837 while (bytes) {
838 struct page *page = folio_page(folio, offset >> PAGE_SHIFT);
> 839 unsigned b = min(bytes, PAGE_SIZE - (offset & PAGE_MASK));
840 unsigned r = __copy_page_from_iter_atomic(page, offset, b, i);
841
842 offset += r;
843 bytes -= r;
844 ret += r;
845
846 if (r != b)
847 break;
848 }
849 #else
850 ret = __copy_page_from_iter_atomic(&folio->page, offset, bytes, i);
851 #endif
852
853 return ret;
854 }
855 EXPORT_SYMBOL(copy_folio_from_iter_atomic);
856

--
0-DAY CI Kernel Test Service
https://github.com/intel/lkp-tests