Re: [PATCH 2/2] btrfs: handle bio split errors for append

[kernel test robot <lkp@intel.com>]

Hi Keith,

kernel test robot noticed the following build warnings:

[auto build test WARNING on xfs-linux/for-next]
[also build test WARNING on kdave/for-next linus/master v6.18-rc2 next-20251021]
[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/Keith-Busch/btrfs-handle-bio-split-errors-for-append/20251020-224536
base:   https://git.kernel.org/pub/scm/fs/xfs/xfs-linux.git for-next
patch link:    https://lore.kernel.org/r/20251020144356.693288-2-kbusch%40meta.com
patch subject: [PATCH 2/2] btrfs: handle bio split errors for append
config: i386-buildonly-randconfig-005-20251021 (https://download.01.org/0day-ci/archive/20251022/202510220421.KBMIIY8p-lkp@intel.com/config)
compiler: gcc-14 (Debian 14.2.0-19) 14.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20251022/202510220421.KBMIIY8p-lkp@intel.com/reproduce)

If you fix the issue in a separate patch/commit (i.e. not just a new version of
the same patch/commit), kindly add following tags
| Reported-by: kernel test robot <lkp@intel.com>
| Closes: https://lore.kernel.org/oe-kbuild-all/202510220421.KBMIIY8p-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/build_bug.h:5,
                    from arch/x86/include/asm/current.h:5,
                    from include/linux/sched.h:12,
                    from include/linux/mempool.h:8,
                    from include/linux/bio.h:8,
                    from fs/btrfs/bio.c:7:
   fs/btrfs/bio.c: In function 'btrfs_submit_chunk':
>> include/linux/err.h:28:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
      28 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
         |                                                 ^
   include/linux/compiler.h:32:55: note: in definition of macro '__branch_check__'
      32 |                         ______r = __builtin_expect(!!(x), expect);      \
         |                                                       ^
   include/linux/err.h:28:25: note: in expansion of macro 'unlikely'
      28 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
         |                         ^~~~~~~~
   fs/btrfs/bio.c:692:21: note: in expansion of macro 'IS_ERR_VALUE'
     692 |                 if (IS_ERR_VALUE(map_length)) {
         |                     ^~~~~~~~~~~~
>> include/linux/err.h:28:49: warning: cast to pointer from integer of different size [-Wint-to-pointer-cast]
      28 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
         |                                                 ^
   include/linux/compiler.h:34:54: note: in definition of macro '__branch_check__'
      34 |                                              expect, is_constant);      \
         |                                                      ^~~~~~~~~~~
   include/linux/err.h:28:25: note: in expansion of macro 'unlikely'
      28 | #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
         |                         ^~~~~~~~
   fs/btrfs/bio.c:692:21: note: in expansion of macro 'IS_ERR_VALUE'
     692 |                 if (IS_ERR_VALUE(map_length)) {
         |                     ^~~~~~~~~~~~


vim +28 include/linux/err.h

ebba5f9fcb88230 Randy Dunlap   2006-09-27  21  
4d744ce9d5d7cf0 James Seo      2023-05-09  22  /**
4d744ce9d5d7cf0 James Seo      2023-05-09  23   * IS_ERR_VALUE - Detect an error pointer.
4d744ce9d5d7cf0 James Seo      2023-05-09  24   * @x: The pointer to check.
4d744ce9d5d7cf0 James Seo      2023-05-09  25   *
4d744ce9d5d7cf0 James Seo      2023-05-09  26   * Like IS_ERR(), but does not generate a compiler warning if result is unused.
4d744ce9d5d7cf0 James Seo      2023-05-09  27   */
aa00edc1287a693 Linus Torvalds 2016-05-27 @28  #define IS_ERR_VALUE(x) unlikely((unsigned long)(void *)(x) >= (unsigned long)-MAX_ERRNO)
07ab67c8d0d7c10 Linus Torvalds 2005-05-19  29  

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