Re: [PATCH 10/10] mm, treewide: Redefine MAX_ORDER sanely

[Kirill A. Shutemov]

On Wed, Mar 15, 2023 at 11:26:51PM +0800, kernel test robot wrote:
> Hi Kirill,
> 
> Thank you for the patch! Perhaps something to improve:
> 
> [auto build test WARNING on akpm-mm/mm-everything]
> [also build test WARNING on powerpc/next powerpc/fixes linus/master v6.3-rc2 next-20230315]
> [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/Kirill-A-Shutemov/sparc-mm-Fix-MAX_ORDER-usage-in-tsb_grow/20230315-193254
> base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
> patch link:    https://lore.kernel.org/r/20230315113133.11326-11-kirill.shutemov%40linux.intel.com
> patch subject: [PATCH 10/10] mm, treewide: Redefine MAX_ORDER sanely
> config: arm-randconfig-r033-20230313 (https://download.01.org/0day-ci/archive/20230315/202303152343.D93IbJmn-lkp@xxxxxxxxx/config)
> compiler: clang version 17.0.0 (https://github.com/llvm/llvm-project 67409911353323ca5edf2049ef0df54132fa1ca7)
> 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://github.com/intel-lab-lkp/linux/commit/ccefb5df94c3c6c966f6f583d60c9d9c832b7a34
>         git remote add linux-review https://github.com/intel-lab-lkp/linux
>         git fetch --no-tags linux-review Kirill-A-Shutemov/sparc-mm-Fix-MAX_ORDER-usage-in-tsb_grow/20230315-193254
>         git checkout ccefb5df94c3c6c966f6f583d60c9d9c832b7a34
>         # save the config file
>         mkdir build_dir && cp config build_dir/.config
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm olddefconfig
>         COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=arm 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/202303152343.D93IbJmn-lkp@xxxxxxxxx/
> 
> All warnings (new ones prefixed by >>):
> 
> >> mm/memblock.c:2046:11: warning: comparison of distinct pointer types ('typeof (11) *' (aka 'int *') and 'typeof (__ffs(start)) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types]
>                    order = min(MAX_ORDER, __ffs(start));

The fixup:

diff --git a/mm/memblock.c b/mm/memblock.c
index 338b8cb0793e..7911224b1ed3 100644
--- a/mm/memblock.c
+++ b/mm/memblock.c
@@ -2043,7 +2043,7 @@ static void __init __free_pages_memory(unsigned long start, unsigned long end)
 	int order;
 
 	while (start < end) {
-		order = min(MAX_ORDER, __ffs(start));
+		order = min_t(int, MAX_ORDER, __ffs(start));
 
 		while (start + (1UL << order) > end)
 			order--;
-- 
  Kiryl Shutsemau / Kirill A. Shutemov