linux-kernel - Re: [PATCH 23/32] iov_iter: copy_folio_from_iter

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <202305101003.uncpRKqA-lkp@intel.com>
Date:   Wed, 10 May 2023 10:20:11 +0800
From:   kernel test robot <lkp@...el.com>
To:     Kent Overstreet <kmo@...erainc.com>, linux-kernel@...r.kernel.org,
        linux-fsdevel@...r.kernel.org, linux-bcachefs@...r.kernel.org
Cc:     llvm@...ts.linux.dev, oe-kbuild-all@...ts.linux.dev,
        Kent Overstreet <kmo@...erainc.com>,
        Alexander Viro <viro@...iv.linux.org.uk>,
        Matthew Wilcox <willy@...radead.org>
Subject: Re: [PATCH 23/32] iov_iter: copy_folio_from_iter_atomic()

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-20230509]
[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: i386-randconfig-a002 (https://download.01.org/0day-ci/archive/20230510/202305101003.uncpRKqA-lkp@intel.com/config)
compiler: clang version 14.0.6 (https://github.com/llvm/llvm-project f28c006a5895fc0e329fe15fead81e37457cb1d1)
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
        # 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=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 olddefconfig
        COMPILER_INSTALL_PATH=$HOME/0day COMPILER=clang make.cross W=1 O=build_dir ARCH=i386 SHELL=/bin/bash

If you fix the issue, kindly add following tag where applicable
| Reported-by: kernel test robot <lkp@...el.com>
| Link: https://lore.kernel.org/oe-kbuild-all/202305101003.uncpRKqA-lkp@intel.com/

All warnings (new ones prefixed by >>):

>> lib/iov_iter.c:839:16: warning: comparison of distinct pointer types ('typeof (bytes) *' (aka 'unsigned int *') and 'typeof (((1UL) << 12) - (offset & (~(((1UL) << 12) - 1)))) *' (aka 'unsigned long *')) [-Wcompare-distinct-pointer-types]
                   unsigned b = min(bytes, PAGE_SIZE - (offset & PAGE_MASK));
                                ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
   include/linux/minmax.h:67:19: note: expanded from macro 'min'
   #define min(x, y)       __careful_cmp(x, y, <)
                           ^~~~~~~~~~~~~~~~~~~~~~
   include/linux/minmax.h:36:24: note: expanded from macro '__careful_cmp'
           __builtin_choose_expr(__safe_cmp(x, y), \
                                 ^~~~~~~~~~~~~~~~
   include/linux/minmax.h:26:4: note: expanded from macro '__safe_cmp'
                   (__typecheck(x, y) && __no_side_effects(x, y))
                    ^~~~~~~~~~~~~~~~~
   include/linux/minmax.h:20:28: note: expanded from macro '__typecheck'
           (!!(sizeof((typeof(x) *)1 == (typeof(y) *)1)))
                      ~~~~~~~~~~~~~~ ^  ~~~~~~~~~~~~~~
   1 warning generated.


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