diff mbox series

[next,resend,5/5] minmax: Relax check to allow comparison between int and small unsigned constants.

Message ID 48c2cd0407f14859919d4fcbe526234a@AcuMS.aculab.com
State New
Headers
Series minmax: Relax type checks in min() and max(). |

Commit Message

David Laight July 25, 2023, 11:54 a.m. UTC 
  Convert constants between 0 and INT_MAX to 'int' prior to comparisons
so that min(signed_var, 20u) and, more commonly, min(signed_var, sizeof())
are both valid.

Signed-off-by: David Laight <david.laight@aculab.com>
---

Resend as reply to 0/5

 include/linux/minmax.h | 35 +++++++++++++++++++++++------------
 1 file changed, 23 insertions(+), 12 deletions(-)

Comments

kernel test robot July 25, 2023, 7:36 p.m. UTC | #1 
Hi David,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master v6.5-rc3 next-20230725]
[cannot apply to next-20230725]
[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/David-Laight/minmax-Allow-min-max-clamp-if-the-arguments-have-the-same-signedness/20230725-204940
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/48c2cd0407f14859919d4fcbe526234a%40AcuMS.aculab.com
patch subject: [PATCH next resend 5/5] minmax: Relax check to allow comparison between int and small unsigned constants.
config: riscv-randconfig-r024-20230725 (https://download.01.org/0day-ci/archive/20230726/202307260303.3ftEpZRU-lkp@intel.com/config)
compiler: riscv32-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230726/202307260303.3ftEpZRU-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/202307260303.3ftEpZRU-lkp@intel.com/

All warnings (new ones prefixed by >>):

   In file included from include/linux/kernel.h:27,
                    from include/linux/cpumask.h:10,
                    from include/linux/smp.h:13,
                    from include/linux/lockdep.h:14,
                    from include/linux/mutex.h:17,
                    from include/linux/notifier.h:14,
                    from include/linux/kprobes.h:21,
                    from include/linux/kgdb.h:19,
                    from include/linux/fb.h:6,
                    from drivers/gpu/drm/drm_modes.c:35:
   drivers/gpu/drm/drm_modes.c: In function 'drm_mode_parse_command_line_for_connector':
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:36:27: note: in definition of macro '__cmp'
      36 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
         |                           ^
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:47:27: note: in expansion of macro '__int_const'
      47 |                 __cmp(op, __int_const(x), __int_const(y)),      \
         |                           ^~~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:36:45: note: in definition of macro '__cmp'
      36 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
         |                                             ^
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:47:43: note: in expansion of macro '__int_const'
      47 |                 __cmp(op, __int_const(x), __int_const(y)),      \
         |                                           ^~~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:36:51: note: in definition of macro '__cmp'
      36 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
         |                                                   ^
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:47:27: note: in expansion of macro '__int_const'
      47 |                 __cmp(op, __int_const(x), __int_const(y)),      \
         |                           ^~~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:36:57: note: in definition of macro '__cmp'
      36 | #define __cmp(op, x, y) ((x) __cmp_op_##op (y) ? (x) : (y))
         |                                                         ^
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:47:43: note: in expansion of macro '__int_const'
      47 |                 __cmp(op, __int_const(x), __int_const(y)),      \
         |                                           ^~~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:39:16: note: in expansion of macro '__int_const'
      39 |         typeof(__int_const(x)) unique_x = (x);          \
         |                ^~~~~~~~~~~
   include/linux/minmax.h:48:17: note: in expansion of macro '__cmp_once'
      48 |                 __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
         |                 ^~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/minmax.h:25:47: note: in expansion of macro '__is_noneg_int'
      25 | #define __int_const(x)  __builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
         |                                               ^~~~~~~~~~~~~~
   include/linux/minmax.h:40:16: note: in expansion of macro '__int_const'
      40 |         typeof(__int_const(y)) unique_y = (y);          \
         |                ^~~~~~~~~~~
   include/linux/minmax.h:48:17: note: in expansion of macro '__cmp_once'
      48 |                 __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
         |                 ^~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
   In file included from include/linux/init.h:5,
                    from include/linux/printk.h:6,
                    from include/asm-generic/bug.h:22,
                    from arch/riscv/include/asm/bug.h:83,
                    from include/linux/bug.h:5,
                    from arch/riscv/include/asm/cmpxchg.h:9,
                    from arch/riscv/include/asm/atomic.h:19,
                    from include/linux/atomic.h:7,
                    from include/linux/refcount.h:95,
                    from include/linux/fb.h:5:
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/minmax.h:41:9: note: in expansion of macro 'static_assert'
      41 |         static_assert(__types_ok(x, y),                 \
         |         ^~~~~~~~~~~~~
   include/linux/minmax.h:31:17: note: in expansion of macro '__is_noneg_int'
      31 |                 __is_noneg_int(x) || __is_noneg_int(y))
         |                 ^~~~~~~~~~~~~~
   include/linux/minmax.h:41:23: note: in expansion of macro '__types_ok'
      41 |         static_assert(__types_ok(x, y),                 \
         |                       ^~~~~~~~~~
   include/linux/minmax.h:48:17: note: in expansion of macro '__cmp_once'
      48 |                 __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
         |                 ^~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~
>> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
      23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
         |                      ^~
   include/linux/build_bug.h:78:56: note: in definition of macro '__static_assert'
      78 | #define __static_assert(expr, msg, ...) _Static_assert(expr, msg)
         |                                                        ^~~~
   include/linux/minmax.h:41:9: note: in expansion of macro 'static_assert'
      41 |         static_assert(__types_ok(x, y),                 \
         |         ^~~~~~~~~~~~~
   include/linux/minmax.h:31:38: note: in expansion of macro '__is_noneg_int'
      31 |                 __is_noneg_int(x) || __is_noneg_int(y))
         |                                      ^~~~~~~~~~~~~~
   include/linux/minmax.h:41:23: note: in expansion of macro '__types_ok'
      41 |         static_assert(__types_ok(x, y),                 \
         |                       ^~~~~~~~~~
   include/linux/minmax.h:48:17: note: in expansion of macro '__cmp_once'
      48 |                 __cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
         |                 ^~~~~~~~~~
   include/linux/minmax.h:81:25: note: in expansion of macro '__careful_cmp'
      81 | #define max(x, y)       __careful_cmp(max, x, y)
         |                         ^~~~~~~~~~~~~
   drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
    2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
         |                             ^~~


vim +23 include/linux/minmax.h

     6	
     7	/*
     8	 * min()/max()/clamp() macros must accomplish three things:
     9	 *
    10	 * - Avoid multiple evaluations of the arguments (so side-effects like
    11	 *   "x++" happen only once) when non-constant.
    12	 * - Perform signed v unsigned type-checking (to generate compile
    13	 *   errors instead of nasty runtime surprises).
    14	 *   Constants from 0 to INT_MAX are cast to (int) so can be used
    15	 *   in comparisons with signed types.
    16	 * - Retain result as a constant expressions when called with only
    17	 *   constant expressions (to avoid tripping VLA warnings in stack
    18	 *   allocation usage).
    19	 */
    20	
    21	#define __is_noneg_int(x)					\
    22		__builtin_choose_expr(!__is_constexpr(x), false, 	\
  > 23			((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
    24
David Laight July 26, 2023, 9:29 a.m. UTC | #2 
From: kernel test robot <lkp@intel.com>
> Sent: 25 July 2023 20:37
> 
...
>    drivers/gpu/drm/drm_modes.c: In function 'drm_mode_parse_command_line_for_connector':
> >> include/linux/minmax.h:23:22: warning: ordered comparison of pointer with integer zero [-Wextra]
>       23 |                 ((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
>          |                      ^~
...
>    drivers/gpu/drm/drm_modes.c:2474:29: note: in expansion of macro 'max'
>     2474 |                 extra_ptr = max(bpp_end_ptr, refresh_end_ptr);
>          |                             ^~~

There are a handful of annoying uses of min/max with pointers.
I'll fix this in v2 by adding a cast to the 0.
(I was expecting an error for unsigned types.)

	David

-
Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK
Registration No: 1397386 (Wales)
kernel test robot July 27, 2023, 5:20 a.m. UTC | #3 
Hi David,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master crng-random/master v6.5-rc3 next-20230726]
[cannot apply to next-20230725]
[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/David-Laight/minmax-Allow-min-max-clamp-if-the-arguments-have-the-same-signedness/20230725-204940
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/48c2cd0407f14859919d4fcbe526234a%40AcuMS.aculab.com
patch subject: [PATCH next resend 5/5] minmax: Relax check to allow comparison between int and small unsigned constants.
config: x86_64-randconfig-r071-20230725 (https://download.01.org/0day-ci/archive/20230727/202307271340.F1VOMz4L-lkp@intel.com/config)
compiler: gcc-12 (Debian 12.2.0-14) 12.2.0
reproduce: (https://download.01.org/0day-ci/archive/20230727/202307271340.F1VOMz4L-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/202307271340.F1VOMz4L-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (>=):
>> mm/percpu.c:3102:24: sparse:    void *ptr
>> mm/percpu.c:3102:24: sparse:    int
>> mm/percpu.c:3102:24: sparse: sparse: bad constant expression type
>> mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (>=):
>> mm/percpu.c:3102:24: sparse:    void *[assigned] ptr
>> mm/percpu.c:3102:24: sparse:    int
>> mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (>=):
>> mm/percpu.c:3102:24: sparse:    void *base
>> mm/percpu.c:3102:24: sparse:    int
>> mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (>=):
>> mm/percpu.c:3102:24: sparse:    void *[assigned] ptr
>> mm/percpu.c:3102:24: sparse:    int
>> mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (>=):
>> mm/percpu.c:3102:24: sparse:    void *base
>> mm/percpu.c:3102:24: sparse:    int
   mm/percpu.c:3102:24: sparse: sparse: incompatible types for operation (<):
   mm/percpu.c:3102:24: sparse:    bad type __UNIQUE_ID___x458
   mm/percpu.c:3102:24: sparse:    bad type __UNIQUE_ID___y459
--
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (>=):
>> fs/ntfs3/lznt.c:157:16: sparse:    unsigned char [usertype] *
>> fs/ntfs3/lznt.c:157:16: sparse:    int
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: bad constant expression type
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (>=):
>> fs/ntfs3/lznt.c:157:16: sparse:    unsigned char [usertype] *
>> fs/ntfs3/lznt.c:157:16: sparse:    int
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (>=):
>> fs/ntfs3/lznt.c:157:16: sparse:    unsigned char [usertype] *cmpr_end
>> fs/ntfs3/lznt.c:157:16: sparse:    int
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (>=):
>> fs/ntfs3/lznt.c:157:16: sparse:    unsigned char [usertype] *
>> fs/ntfs3/lznt.c:157:16: sparse:    int
>> fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (>=):
>> fs/ntfs3/lznt.c:157:16: sparse:    unsigned char [usertype] *cmpr_end
>> fs/ntfs3/lznt.c:157:16: sparse:    int
   fs/ntfs3/lznt.c:157:16: sparse: sparse: incompatible types for operation (<):
   fs/ntfs3/lznt.c:157:16: sparse:    bad type __UNIQUE_ID___x333
   fs/ntfs3/lznt.c:157:16: sparse:    bad type __UNIQUE_ID___y334

vim +3102 mm/percpu.c

3c9a024fde58b0 Tejun Heo       2010-09-09  3022  
3c9a024fde58b0 Tejun Heo       2010-09-09  3023  #if defined(BUILD_EMBED_FIRST_CHUNK)
66c3a75772247c Tejun Heo       2009-03-10  3024  /**
66c3a75772247c Tejun Heo       2009-03-10  3025   * pcpu_embed_first_chunk - embed the first percpu chunk into bootmem
66c3a75772247c Tejun Heo       2009-03-10  3026   * @reserved_size: the size of reserved percpu area in bytes
4ba6ce250e406b Tejun Heo       2010-06-27  3027   * @dyn_size: minimum free size for dynamic allocation in bytes
c8826dd538602d Tejun Heo       2009-08-14  3028   * @atom_size: allocation atom size
c8826dd538602d Tejun Heo       2009-08-14  3029   * @cpu_distance_fn: callback to determine distance between cpus, optional
1ca3fb3abd2b61 Kefeng Wang     2022-01-19  3030   * @cpu_to_nd_fn: callback to convert cpu to it's node, optional
66c3a75772247c Tejun Heo       2009-03-10  3031   *
66c3a75772247c Tejun Heo       2009-03-10  3032   * This is a helper to ease setting up embedded first percpu chunk and
66c3a75772247c Tejun Heo       2009-03-10  3033   * can be called where pcpu_setup_first_chunk() is expected.
66c3a75772247c Tejun Heo       2009-03-10  3034   *
66c3a75772247c Tejun Heo       2009-03-10  3035   * If this function is used to setup the first chunk, it is allocated
23f917169ef157 Kefeng Wang     2022-01-19  3036   * by calling pcpu_fc_alloc and used as-is without being mapped into
c8826dd538602d Tejun Heo       2009-08-14  3037   * vmalloc area.  Allocations are always whole multiples of @atom_size
c8826dd538602d Tejun Heo       2009-08-14  3038   * aligned to @atom_size.
c8826dd538602d Tejun Heo       2009-08-14  3039   *
c8826dd538602d Tejun Heo       2009-08-14  3040   * This enables the first chunk to piggy back on the linear physical
c8826dd538602d Tejun Heo       2009-08-14  3041   * mapping which often uses larger page size.  Please note that this
c8826dd538602d Tejun Heo       2009-08-14  3042   * can result in very sparse cpu->unit mapping on NUMA machines thus
c8826dd538602d Tejun Heo       2009-08-14  3043   * requiring large vmalloc address space.  Don't use this allocator if
c8826dd538602d Tejun Heo       2009-08-14  3044   * vmalloc space is not orders of magnitude larger than distances
c8826dd538602d Tejun Heo       2009-08-14  3045   * between node memory addresses (ie. 32bit NUMA machines).
66c3a75772247c Tejun Heo       2009-03-10  3046   *
4ba6ce250e406b Tejun Heo       2010-06-27  3047   * @dyn_size specifies the minimum dynamic area size.
66c3a75772247c Tejun Heo       2009-03-10  3048   *
66c3a75772247c Tejun Heo       2009-03-10  3049   * If the needed size is smaller than the minimum or specified unit
23f917169ef157 Kefeng Wang     2022-01-19  3050   * size, the leftover is returned using pcpu_fc_free.
66c3a75772247c Tejun Heo       2009-03-10  3051   *
66c3a75772247c Tejun Heo       2009-03-10  3052   * RETURNS:
fb435d5233f8b6 Tejun Heo       2009-08-14  3053   * 0 on success, -errno on failure.
66c3a75772247c Tejun Heo       2009-03-10  3054   */
4ba6ce250e406b Tejun Heo       2010-06-27  3055  int __init pcpu_embed_first_chunk(size_t reserved_size, size_t dyn_size,
c8826dd538602d Tejun Heo       2009-08-14  3056  				  size_t atom_size,
c8826dd538602d Tejun Heo       2009-08-14  3057  				  pcpu_fc_cpu_distance_fn_t cpu_distance_fn,
23f917169ef157 Kefeng Wang     2022-01-19  3058  				  pcpu_fc_cpu_to_node_fn_t cpu_to_nd_fn)
66c3a75772247c Tejun Heo       2009-03-10  3059  {
c8826dd538602d Tejun Heo       2009-08-14  3060  	void *base = (void *)ULONG_MAX;
c8826dd538602d Tejun Heo       2009-08-14  3061  	void **areas = NULL;
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3062  	struct pcpu_alloc_info *ai;
93c76b6b2faaad zijun_hu        2016-10-05  3063  	size_t size_sum, areas_size;
93c76b6b2faaad zijun_hu        2016-10-05  3064  	unsigned long max_distance;
163fa23435cc9c Kefeng Wang     2019-07-03  3065  	int group, i, highest_group, rc = 0;
66c3a75772247c Tejun Heo       2009-03-10  3066  
c8826dd538602d Tejun Heo       2009-08-14  3067  	ai = pcpu_build_alloc_info(reserved_size, dyn_size, atom_size,
c8826dd538602d Tejun Heo       2009-08-14  3068  				   cpu_distance_fn);
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3069  	if (IS_ERR(ai))
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3070  		return PTR_ERR(ai);
66c3a75772247c Tejun Heo       2009-03-10  3071  
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3072  	size_sum = ai->static_size + ai->reserved_size + ai->dyn_size;
c8826dd538602d Tejun Heo       2009-08-14  3073  	areas_size = PFN_ALIGN(ai->nr_groups * sizeof(void *));
fa8a7094ba1679 Tejun Heo       2009-06-22  3074  
26fb3dae0a1ec7 Mike Rapoport   2019-03-11  3075  	areas = memblock_alloc(areas_size, SMP_CACHE_BYTES);
c8826dd538602d Tejun Heo       2009-08-14  3076  	if (!areas) {
fb435d5233f8b6 Tejun Heo       2009-08-14  3077  		rc = -ENOMEM;
c8826dd538602d Tejun Heo       2009-08-14  3078  		goto out_free;
fa8a7094ba1679 Tejun Heo       2009-06-22  3079  	}
66c3a75772247c Tejun Heo       2009-03-10  3080  
9b7396624a7b50 zijun_hu        2016-10-05  3081  	/* allocate, copy and determine base address & max_distance */
9b7396624a7b50 zijun_hu        2016-10-05  3082  	highest_group = 0;
c8826dd538602d Tejun Heo       2009-08-14  3083  	for (group = 0; group < ai->nr_groups; group++) {
c8826dd538602d Tejun Heo       2009-08-14  3084  		struct pcpu_group_info *gi = &ai->groups[group];
c8826dd538602d Tejun Heo       2009-08-14  3085  		unsigned int cpu = NR_CPUS;
c8826dd538602d Tejun Heo       2009-08-14  3086  		void *ptr;
c8826dd538602d Tejun Heo       2009-08-14  3087  
c8826dd538602d Tejun Heo       2009-08-14  3088  		for (i = 0; i < gi->nr_units && cpu == NR_CPUS; i++)
c8826dd538602d Tejun Heo       2009-08-14  3089  			cpu = gi->cpu_map[i];
c8826dd538602d Tejun Heo       2009-08-14  3090  		BUG_ON(cpu == NR_CPUS);
c8826dd538602d Tejun Heo       2009-08-14  3091  
c8826dd538602d Tejun Heo       2009-08-14  3092  		/* allocate space for the whole group */
23f917169ef157 Kefeng Wang     2022-01-19  3093  		ptr = pcpu_fc_alloc(cpu, gi->nr_units * ai->unit_size, atom_size, cpu_to_nd_fn);
c8826dd538602d Tejun Heo       2009-08-14  3094  		if (!ptr) {
c8826dd538602d Tejun Heo       2009-08-14  3095  			rc = -ENOMEM;
c8826dd538602d Tejun Heo       2009-08-14  3096  			goto out_free_areas;
c8826dd538602d Tejun Heo       2009-08-14  3097  		}
f528f0b8e53d73 Catalin Marinas 2011-09-26  3098  		/* kmemleak tracks the percpu allocations separately */
a317ebccaa3609 Patrick Wang    2022-07-05  3099  		kmemleak_ignore_phys(__pa(ptr));
c8826dd538602d Tejun Heo       2009-08-14  3100  		areas[group] = ptr;
c8826dd538602d Tejun Heo       2009-08-14  3101  
c8826dd538602d Tejun Heo       2009-08-14 @3102  		base = min(ptr, base);
9b7396624a7b50 zijun_hu        2016-10-05  3103  		if (ptr > areas[highest_group])
9b7396624a7b50 zijun_hu        2016-10-05  3104  			highest_group = group;
9b7396624a7b50 zijun_hu        2016-10-05  3105  	}
9b7396624a7b50 zijun_hu        2016-10-05  3106  	max_distance = areas[highest_group] - base;
9b7396624a7b50 zijun_hu        2016-10-05  3107  	max_distance += ai->unit_size * ai->groups[highest_group].nr_units;
9b7396624a7b50 zijun_hu        2016-10-05  3108  
9b7396624a7b50 zijun_hu        2016-10-05  3109  	/* warn if maximum distance is further than 75% of vmalloc space */
9b7396624a7b50 zijun_hu        2016-10-05  3110  	if (max_distance > VMALLOC_TOTAL * 3 / 4) {
9b7396624a7b50 zijun_hu        2016-10-05  3111  		pr_warn("max_distance=0x%lx too large for vmalloc space 0x%lx\n",
9b7396624a7b50 zijun_hu        2016-10-05  3112  				max_distance, VMALLOC_TOTAL);
9b7396624a7b50 zijun_hu        2016-10-05  3113  #ifdef CONFIG_NEED_PER_CPU_PAGE_FIRST_CHUNK
9b7396624a7b50 zijun_hu        2016-10-05  3114  		/* and fail if we have fallback */
9b7396624a7b50 zijun_hu        2016-10-05  3115  		rc = -EINVAL;
9b7396624a7b50 zijun_hu        2016-10-05  3116  		goto out_free_areas;
9b7396624a7b50 zijun_hu        2016-10-05  3117  #endif
42b64281453249 Tejun Heo       2012-04-27  3118  	}
42b64281453249 Tejun Heo       2012-04-27  3119  
42b64281453249 Tejun Heo       2012-04-27  3120  	/*
42b64281453249 Tejun Heo       2012-04-27  3121  	 * Copy data and free unused parts.  This should happen after all
42b64281453249 Tejun Heo       2012-04-27  3122  	 * allocations are complete; otherwise, we may end up with
42b64281453249 Tejun Heo       2012-04-27  3123  	 * overlapping groups.
42b64281453249 Tejun Heo       2012-04-27  3124  	 */
42b64281453249 Tejun Heo       2012-04-27  3125  	for (group = 0; group < ai->nr_groups; group++) {
42b64281453249 Tejun Heo       2012-04-27  3126  		struct pcpu_group_info *gi = &ai->groups[group];
42b64281453249 Tejun Heo       2012-04-27  3127  		void *ptr = areas[group];
66c3a75772247c Tejun Heo       2009-03-10  3128  
c8826dd538602d Tejun Heo       2009-08-14  3129  		for (i = 0; i < gi->nr_units; i++, ptr += ai->unit_size) {
c8826dd538602d Tejun Heo       2009-08-14  3130  			if (gi->cpu_map[i] == NR_CPUS) {
c8826dd538602d Tejun Heo       2009-08-14  3131  				/* unused unit, free whole */
23f917169ef157 Kefeng Wang     2022-01-19  3132  				pcpu_fc_free(ptr, ai->unit_size);
c8826dd538602d Tejun Heo       2009-08-14  3133  				continue;
c8826dd538602d Tejun Heo       2009-08-14  3134  			}
c8826dd538602d Tejun Heo       2009-08-14  3135  			/* copy and return the unused part */
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3136  			memcpy(ptr, __per_cpu_load, ai->static_size);
23f917169ef157 Kefeng Wang     2022-01-19  3137  			pcpu_fc_free(ptr + size_sum, ai->unit_size - size_sum);
c8826dd538602d Tejun Heo       2009-08-14  3138  		}
66c3a75772247c Tejun Heo       2009-03-10  3139  	}
66c3a75772247c Tejun Heo       2009-03-10  3140  
c8826dd538602d Tejun Heo       2009-08-14  3141  	/* base address is now known, determine group base offsets */
6ea529a2037ce6 Tejun Heo       2009-09-24  3142  	for (group = 0; group < ai->nr_groups; group++) {
c8826dd538602d Tejun Heo       2009-08-14  3143  		ai->groups[group].base_offset = areas[group] - base;
6ea529a2037ce6 Tejun Heo       2009-09-24  3144  	}
c8826dd538602d Tejun Heo       2009-08-14  3145  
00206a69ee32f0 Matteo Croce    2019-03-18  3146  	pr_info("Embedded %zu pages/cpu s%zu r%zu d%zu u%zu\n",
00206a69ee32f0 Matteo Croce    2019-03-18  3147  		PFN_DOWN(size_sum), ai->static_size, ai->reserved_size,
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3148  		ai->dyn_size, ai->unit_size);
66c3a75772247c Tejun Heo       2009-03-10  3149  
163fa23435cc9c Kefeng Wang     2019-07-03  3150  	pcpu_setup_first_chunk(ai, base);
c8826dd538602d Tejun Heo       2009-08-14  3151  	goto out_free;
c8826dd538602d Tejun Heo       2009-08-14  3152  
c8826dd538602d Tejun Heo       2009-08-14  3153  out_free_areas:
c8826dd538602d Tejun Heo       2009-08-14  3154  	for (group = 0; group < ai->nr_groups; group++)
f851c8d8583891 Michael Holzheu 2013-09-17  3155  		if (areas[group])
23f917169ef157 Kefeng Wang     2022-01-19  3156  			pcpu_fc_free(areas[group],
c8826dd538602d Tejun Heo       2009-08-14  3157  				ai->groups[group].nr_units * ai->unit_size);
c8826dd538602d Tejun Heo       2009-08-14  3158  out_free:
fd1e8a1fe2b54d Tejun Heo       2009-08-14  3159  	pcpu_free_alloc_info(ai);
c8826dd538602d Tejun Heo       2009-08-14  3160  	if (areas)
4421cca0a3e483 Mike Rapoport   2021-11-05  3161  		memblock_free(areas, areas_size);
fb435d5233f8b6 Tejun Heo       2009-08-14  3162  	return rc;
fa8a7094ba1679 Tejun Heo       2009-06-22  3163  }
3c9a024fde58b0 Tejun Heo       2010-09-09  3164  #endif /* BUILD_EMBED_FIRST_CHUNK */
d4b95f80399471 Tejun Heo       2009-07-04  3165
kernel test robot July 28, 2023, 7:15 a.m. UTC | #4 
Hi David,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master v6.5-rc3 next-20230727]
[cannot apply to next-20230725]
[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/David-Laight/minmax-Allow-min-max-clamp-if-the-arguments-have-the-same-signedness/20230725-204940
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/48c2cd0407f14859919d4fcbe526234a%40AcuMS.aculab.com
patch subject: [PATCH next resend 5/5] minmax: Relax check to allow comparison between int and small unsigned constants.
config: microblaze-randconfig-r092-20230725 (https://download.01.org/0day-ci/archive/20230728/202307281520.WNoM3bxU-lkp@intel.com/config)
compiler: microblaze-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230728/202307281520.WNoM3bxU-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/202307281520.WNoM3bxU-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: bad constant expression type
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *end_page
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *end_page
>> crypto/skcipher.c:80:16: sparse:    int
   crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>):
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___x297
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___y298
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *end_page
>> crypto/skcipher.c:80:16: sparse:    int
   crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>):
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___x297
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___y298
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *end_page
>> crypto/skcipher.c:80:16: sparse:    int
   crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>):
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___x297
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___y298
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *start
>> crypto/skcipher.c:80:16: sparse:    int
>> crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>=):
>> crypto/skcipher.c:80:16: sparse:    unsigned char [usertype] *end_page
>> crypto/skcipher.c:80:16: sparse:    int
   crypto/skcipher.c:80:16: sparse: sparse: incompatible types for operation (>):
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___x297
   crypto/skcipher.c:80:16: sparse:    bad type __UNIQUE_ID___y298
--
   drivers/gpu/drm/drm_modes.c: note: in included file (through include/drm/drm_plane.h, include/drm/drm_crtc.h):
   include/drm/drm_color_mgmt.h:52:16: sparse: sparse: bad integer constant expression
   include/drm/drm_color_mgmt.h:52:16: sparse: sparse: static assertion failed: "clamp() low limit (typeof(val))(0) greater than high limit (typeof(val))(max)"
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>=):
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    char *bpp_end_ptr
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    int
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: bad constant expression type
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>=):
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    char *[addressable] bpp_end_ptr
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    int
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>=):
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    char *[addressable] refresh_end_ptr
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    int
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>=):
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    char *[addressable] bpp_end_ptr
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    int
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>=):
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    char *[addressable] refresh_end_ptr
>> drivers/gpu/drm/drm_modes.c:2474:29: sparse:    int
   drivers/gpu/drm/drm_modes.c:2474:29: sparse: sparse: incompatible types for operation (>):
   drivers/gpu/drm/drm_modes.c:2474:29: sparse:    bad type __UNIQUE_ID___x334
   drivers/gpu/drm/drm_modes.c:2474:29: sparse:    bad type __UNIQUE_ID___y335
--
>> net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (>=):
>> net/ceph/osdmap.c:1773:54: sparse:    void *
>> net/ceph/osdmap.c:1773:54: sparse:    int
>> net/ceph/osdmap.c:1773:54: sparse: sparse: bad constant expression type
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2000:46: sparse:    void *
   net/ceph/osdmap.c:2000:46: sparse:    int
   net/ceph/osdmap.c:2000:46: sparse: sparse: bad constant expression type
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2007:57: sparse:    void *
   net/ceph/osdmap.c:2007:57: sparse:    int
   net/ceph/osdmap.c:2007:57: sparse: sparse: bad constant expression type
>> net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (>=):
>> net/ceph/osdmap.c:1773:54: sparse:    void *
>> net/ceph/osdmap.c:1773:54: sparse:    int
>> net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (>=):
>> net/ceph/osdmap.c:1773:54: sparse:    void *end
>> net/ceph/osdmap.c:1773:54: sparse:    int
>> net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (>=):
>> net/ceph/osdmap.c:1773:54: sparse:    void *
>> net/ceph/osdmap.c:1773:54: sparse:    int
>> net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (>=):
>> net/ceph/osdmap.c:1773:54: sparse:    void *end
>> net/ceph/osdmap.c:1773:54: sparse:    int
   net/ceph/osdmap.c:1773:54: sparse: sparse: incompatible types for operation (<):
   net/ceph/osdmap.c:1773:54: sparse:    bad type __UNIQUE_ID___x318
   net/ceph/osdmap.c:1773:54: sparse:    bad type __UNIQUE_ID___y319
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2000:46: sparse:    void *
   net/ceph/osdmap.c:2000:46: sparse:    int
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2000:46: sparse:    void *end
   net/ceph/osdmap.c:2000:46: sparse:    int
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2000:46: sparse:    void *
   net/ceph/osdmap.c:2000:46: sparse:    int
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2000:46: sparse:    void *end
   net/ceph/osdmap.c:2000:46: sparse:    int
   net/ceph/osdmap.c:2000:46: sparse: sparse: incompatible types for operation (<):
   net/ceph/osdmap.c:2000:46: sparse:    bad type __UNIQUE_ID___x322
   net/ceph/osdmap.c:2000:46: sparse:    bad type __UNIQUE_ID___y323
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2007:57: sparse:    void *
   net/ceph/osdmap.c:2007:57: sparse:    int
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2007:57: sparse:    void *end
   net/ceph/osdmap.c:2007:57: sparse:    int
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2007:57: sparse:    void *
   net/ceph/osdmap.c:2007:57: sparse:    int
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (>=):
   net/ceph/osdmap.c:2007:57: sparse:    void *end
   net/ceph/osdmap.c:2007:57: sparse:    int
   net/ceph/osdmap.c:2007:57: sparse: sparse: incompatible types for operation (<):
   net/ceph/osdmap.c:2007:57: sparse:    bad type __UNIQUE_ID___x324
   net/ceph/osdmap.c:2007:57: sparse:    bad type __UNIQUE_ID___y325
--
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (>=):
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    unsigned char const *const ip_end
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    int
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: bad constant expression type
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (>=):
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    unsigned char const *const ip_end
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    int
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (>=):
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    unsigned char const *
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    int
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (>=):
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    unsigned char const *const ip_end
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    int
>> lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (>=):
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    unsigned char const *
>> lib/lzo/lzo1x_compress.c:53:54: sparse:    int
   lib/lzo/lzo1x_compress.c:53:54: sparse: sparse: incompatible types for operation (<):
   lib/lzo/lzo1x_compress.c:53:54: sparse:    bad type __UNIQUE_ID___x182
   lib/lzo/lzo1x_compress.c:53:54: sparse:    bad type __UNIQUE_ID___y183

vim +80 crypto/skcipher.c

b286d8b1a69066 Herbert Xu 2016-11-22  72  
b286d8b1a69066 Herbert Xu 2016-11-22  73  /* Get a spot of the specified length that does not straddle a page.
b286d8b1a69066 Herbert Xu 2016-11-22  74   * The caller needs to ensure that there is enough space for this operation.
b286d8b1a69066 Herbert Xu 2016-11-22  75   */
b286d8b1a69066 Herbert Xu 2016-11-22  76  static inline u8 *skcipher_get_spot(u8 *start, unsigned int len)
b286d8b1a69066 Herbert Xu 2016-11-22  77  {
b286d8b1a69066 Herbert Xu 2016-11-22  78  	u8 *end_page = (u8 *)(((unsigned long)(start + len - 1)) & PAGE_MASK);
b286d8b1a69066 Herbert Xu 2016-11-22  79  
b286d8b1a69066 Herbert Xu 2016-11-22 @80  	return max(start, end_page);
b286d8b1a69066 Herbert Xu 2016-11-22  81  }
b286d8b1a69066 Herbert Xu 2016-11-22  82
kernel test robot July 28, 2023, 8:08 a.m. UTC | #5 
Hi David,

kernel test robot noticed the following build warnings:

[auto build test WARNING on akpm-mm/mm-everything]
[also build test WARNING on linus/master crng-random/master v6.5-rc3 next-20230728]
[cannot apply to next-20230725]
[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/David-Laight/minmax-Allow-min-max-clamp-if-the-arguments-have-the-same-signedness/20230725-204940
base:   https://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm.git mm-everything
patch link:    https://lore.kernel.org/r/48c2cd0407f14859919d4fcbe526234a%40AcuMS.aculab.com
patch subject: [PATCH next resend 5/5] minmax: Relax check to allow comparison between int and small unsigned constants.
config: xtensa-randconfig-r093-20230725 (https://download.01.org/0day-ci/archive/20230728/202307281556.iTVIR4tJ-lkp@intel.com/config)
compiler: xtensa-linux-gcc (GCC) 12.3.0
reproduce: (https://download.01.org/0day-ci/archive/20230728/202307281556.iTVIR4tJ-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/202307281556.iTVIR4tJ-lkp@intel.com/

sparse warnings: (new ones prefixed by >>)
   mm/kmemleak.c: note: in included file (through arch/xtensa/include/asm/bitops.h, include/linux/bitops.h, include/linux/kernel.h):
   arch/xtensa/include/asm/processor.h:103:2: sparse: sparse: Unsupported xtensa ABI
   arch/xtensa/include/asm/processor.h:133:2: sparse: sparse: Unsupported Xtensa ABI
>> mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (>=):
>> mm/kmemleak.c:1429:32: sparse:    void *
>> mm/kmemleak.c:1429:32: sparse:    int
>> mm/kmemleak.c:1429:32: sparse: sparse: bad constant expression type
>> mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (>=):
>> mm/kmemleak.c:1429:32: sparse:    void *
>> mm/kmemleak.c:1429:32: sparse:    int
>> mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (>=):
>> mm/kmemleak.c:1429:32: sparse:    void *end
>> mm/kmemleak.c:1429:32: sparse:    int
>> mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (>=):
>> mm/kmemleak.c:1429:32: sparse:    void *
>> mm/kmemleak.c:1429:32: sparse:    int
>> mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (>=):
>> mm/kmemleak.c:1429:32: sparse:    void *end
>> mm/kmemleak.c:1429:32: sparse:    int
   mm/kmemleak.c:1429:32: sparse: sparse: incompatible types for operation (<):
   mm/kmemleak.c:1429:32: sparse:    bad type __UNIQUE_ID___x229
   mm/kmemleak.c:1429:32: sparse:    bad type __UNIQUE_ID___y230

vim +1429 mm/kmemleak.c

3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1396  
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1397  /*
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1398   * Scan a memory block corresponding to a kmemleak_object. A condition is
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1399   * that object->use_count >= 1.
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1400   */
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1401  static void scan_object(struct kmemleak_object *object)
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1402  {
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1403  	struct kmemleak_scan_area *area;
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1404  	unsigned long flags;
0c24e061196c21 Patrick Wang     2022-06-11  1405  	void *obj_ptr;
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1406  
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1407  	/*
21ae2956ce289f Uwe Kleine-König 2009-10-07  1408  	 * Once the object->lock is acquired, the corresponding memory block
21ae2956ce289f Uwe Kleine-König 2009-10-07  1409  	 * cannot be freed (the same lock is acquired in delete_object).
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1410  	 */
8c96f1bc6fc49c He Zhe           2020-01-30  1411  	raw_spin_lock_irqsave(&object->lock, flags);
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1412  	if (object->flags & OBJECT_NO_SCAN)
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1413  		goto out;
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1414  	if (!(object->flags & OBJECT_ALLOCATED))
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1415  		/* already freed object */
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1416  		goto out;
0c24e061196c21 Patrick Wang     2022-06-11  1417  
0c24e061196c21 Patrick Wang     2022-06-11  1418  	obj_ptr = object->flags & OBJECT_PHYS ?
0c24e061196c21 Patrick Wang     2022-06-11  1419  		  __va((phys_addr_t)object->pointer) :
0c24e061196c21 Patrick Wang     2022-06-11  1420  		  (void *)object->pointer;
0c24e061196c21 Patrick Wang     2022-06-11  1421  
dba82d9431770e Catalin Marinas  2019-09-23  1422  	if (hlist_empty(&object->area_list) ||
dba82d9431770e Catalin Marinas  2019-09-23  1423  	    object->flags & OBJECT_FULL_SCAN) {
0c24e061196c21 Patrick Wang     2022-06-11  1424  		void *start = obj_ptr;
0c24e061196c21 Patrick Wang     2022-06-11  1425  		void *end = obj_ptr + object->size;
93ada579b0eea0 Catalin Marinas  2015-06-24  1426  		void *next;
af98603dad87e3 Catalin Marinas  2009-08-27  1427  
93ada579b0eea0 Catalin Marinas  2015-06-24  1428  		do {
93ada579b0eea0 Catalin Marinas  2015-06-24 @1429  			next = min(start + MAX_SCAN_SIZE, end);
93ada579b0eea0 Catalin Marinas  2015-06-24  1430  			scan_block(start, next, object);
93ada579b0eea0 Catalin Marinas  2015-06-24  1431  
93ada579b0eea0 Catalin Marinas  2015-06-24  1432  			start = next;
93ada579b0eea0 Catalin Marinas  2015-06-24  1433  			if (start >= end)
93ada579b0eea0 Catalin Marinas  2015-06-24  1434  				break;
af98603dad87e3 Catalin Marinas  2009-08-27  1435  
8c96f1bc6fc49c He Zhe           2020-01-30  1436  			raw_spin_unlock_irqrestore(&object->lock, flags);
af98603dad87e3 Catalin Marinas  2009-08-27  1437  			cond_resched();
8c96f1bc6fc49c He Zhe           2020-01-30  1438  			raw_spin_lock_irqsave(&object->lock, flags);
93ada579b0eea0 Catalin Marinas  2015-06-24  1439  		} while (object->flags & OBJECT_ALLOCATED);
af98603dad87e3 Catalin Marinas  2009-08-27  1440  	} else
b67bfe0d42cac5 Sasha Levin      2013-02-27  1441  		hlist_for_each_entry(area, &object->area_list, node)
c017b4be3e8417 Catalin Marinas  2009-10-28  1442  			scan_block((void *)area->start,
c017b4be3e8417 Catalin Marinas  2009-10-28  1443  				   (void *)(area->start + area->size),
93ada579b0eea0 Catalin Marinas  2015-06-24  1444  				   object);
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1445  out:
8c96f1bc6fc49c He Zhe           2020-01-30  1446  	raw_spin_unlock_irqrestore(&object->lock, flags);
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1447  }
3c7b4e6b8be4c1 Catalin Marinas  2009-06-11  1448
diff mbox series

Patch

diff --git a/include/linux/minmax.h b/include/linux/minmax.h
index baffbe5c855d..27ebab9f21e7 100644
--- a/include/linux/minmax.h
+++ b/include/linux/minmax.h
@@ -7,17 +7,28 @@ 
 /*
  * min()/max()/clamp() macros must accomplish three things:
  *
- * - avoid multiple evaluations of the arguments (so side-effects like
+ * - Avoid multiple evaluations of the arguments (so side-effects like
  *   "x++" happen only once) when non-constant.
- * - perform signed v unsigned type-checking (to generate compile
+ * - Perform signed v unsigned type-checking (to generate compile
  *   errors instead of nasty runtime surprises).
- * - retain result as a constant expressions when called with only
+ *   Constants from 0 to INT_MAX are cast to (int) so can be used
+ *   in comparisons with signed types.
+ * - Retain result as a constant expressions when called with only
  *   constant expressions (to avoid tripping VLA warnings in stack
  *   allocation usage).
  */
-#define __types_ok(x, y) \
-	(is_signed_type(typeof(x)) == is_signed_type(typeof(y)) ||	\
-		is_signed_type(typeof((x) + 0)) == is_signed_type(typeof((y) + 0)))
+
+#define __is_noneg_int(x)					\
+	__builtin_choose_expr(!__is_constexpr(x), false, 	\
+		((x) >= 0 && (x) <= (typeof((x) + 0))(long)__INT_MAX__))
+
+#define __int_const(x)	__builtin_choose_expr(__is_noneg_int(x), (int)(long)(x), (x))
+
+#define __is_signed(x)	is_signed_type(typeof(x))
+#define __types_ok(x, y) 					\
+	(__is_signed(x) == __is_signed(y) ||			\
+		__is_signed((x) + 0) == __is_signed((y) + 0) ||	\
+		__is_noneg_int(x) || __is_noneg_int(y))
 
 #define __cmp_op_min <
 #define __cmp_op_max >
@@ -25,24 +36,24 @@ 
 #define __cmp(op, x, y)	((x) __cmp_op_##op (y) ? (x) : (y))
 
 #define __cmp_once(op, x, y, unique_x, unique_y) ({	\
-	typeof(x) unique_x = (x);			\
-	typeof(y) unique_y = (y);			\
+	typeof(__int_const(x)) unique_x = (x);		\
+	typeof(__int_const(y)) unique_y = (y);		\
 	static_assert(__types_ok(x, y),			\
 		#op "(" #x ", " #y ") signedness error, fix types or consider " #op "_unsigned() before " #op "_t()"); \
 	__cmp(op, unique_x, unique_y); })
 
 #define __careful_cmp(op, x, y)					\
 	__builtin_choose_expr(__is_constexpr((x) - (y)),	\
-		__cmp(op, x, y),				\
+		__cmp(op, __int_const(x), __int_const(y)),	\
 		__cmp_once(op, x, y, __UNIQUE_ID(__x), __UNIQUE_ID(__y)))
 
 #define __clamp(val, lo, hi)	\
 	((val) >= (hi) ? (hi) : ((val) <= (lo) ? (lo) : (val)))
 
 #define __clamp_once(val, lo, hi, unique_val, unique_lo, unique_hi) ({		\
-	typeof(val) unique_val = (val);						\
-	typeof(lo) unique_lo = (lo);						\
-	typeof(hi) unique_hi = (hi);						\
+	typeof(__int_const(val)) unique_val = (val);				\
+	typeof(__int_const(lo)) unique_lo = (lo);				\
+	typeof(__int_const(hi)) unique_hi = (hi);				\
 	static_assert(!__is_constexpr((lo) > (hi)) || (lo) <= (hi),		\
 		"clamp() low limit " #lo " greater than high limit " #hi);	\
 	static_assert(__types_ok(val, lo), "clamp() 'lo' signedness error");	\