Re: [PATCH v8 5/6] PCI: Allow drivers to control VF BAR size

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

Hi Michał,

kernel test robot noticed the following build errors:

[auto build test ERROR on pci/next]
[also build test ERROR on pci/for-linus drm-xe/drm-xe-next drm-exynos/exynos-drm-next linus/master v6.15 next-20250526]
[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/Micha-Winiarski/PCI-IOV-Restore-VF-resizable-BAR-state-after-reset/20250527-054652
base:   https://git.kernel.org/pub/scm/linux/kernel/git/pci/pci.git next
patch link:    https://lore.kernel.org/r/20250526214257.3481760-6-michal.winiarski%40intel.com
patch subject: [PATCH v8 5/6] PCI: Allow drivers to control VF BAR size
config: csky-randconfig-002-20250527 (https://download.01.org/0day-ci/archive/20250527/202505270842.rZMzTQh6-lkp@intel.com/config)
compiler: csky-linux-gcc (GCC) 12.4.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20250527/202505270842.rZMzTQh6-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/202505270842.rZMzTQh6-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from ./arch/csky/include/generated/asm/div64.h:1,
                    from include/linux/math.h:6,
                    from include/linux/kernel.h:27,
                    from include/linux/cpumask.h:11,
                    from include/linux/smp.h:13,
                    from include/linux/lockdep.h:14,
                    from include/linux/mutex.h:17,
                    from include/linux/kernfs.h:11,
                    from include/linux/sysfs.h:16,
                    from include/linux/kobject.h:20,
                    from include/linux/pci.h:35,
                    from drivers/pci/iov.c:13:
   drivers/pci/iov.c: In function 'pci_iov_vf_bar_get_sizes':
   include/asm-generic/div64.h:183:35: warning: comparison of distinct pointer types lacks a cast
     183 |         (void)(((typeof((n)) *)0) == ((uint64_t *)0));  \
         |                                   ^~
   drivers/pci/iov.c:1383:9: note: in expansion of macro 'do_div'
    1383 |         do_div(vf_len, num_vfs);
         |         ^~~~~~
   In file included from include/linux/build_bug.h:5,
                    from include/linux/bitfield.h:10,
                    from drivers/pci/iov.c:10:
   include/asm-generic/div64.h:195:32: warning: right shift count >= width of type [-Wshift-count-overflow]
     195 |         } else if (likely(((n) >> 32) == 0)) {          \
         |                                ^~
   include/linux/compiler.h:76:45: note: in definition of macro 'likely'
      76 | # define likely(x)      __builtin_expect(!!(x), 1)
         |                                             ^
   drivers/pci/iov.c:1383:9: note: in expansion of macro 'do_div'
    1383 |         do_div(vf_len, num_vfs);
         |         ^~~~~~
>> include/asm-generic/div64.h:199:36: error: passing argument 1 of '__div64_32' from incompatible pointer type [-Werror=incompatible-pointer-types]
     199 |                 __rem = __div64_32(&(n), __base);       \
         |                                    ^~~~
         |                                    |
         |                                    resource_size_t * {aka unsigned int *}
   drivers/pci/iov.c:1383:9: note: in expansion of macro 'do_div'
    1383 |         do_div(vf_len, num_vfs);
         |         ^~~~~~
   include/asm-generic/div64.h:174:38: note: expected 'uint64_t *' {aka 'long long unsigned int *'} but argument is of type 'resource_size_t *' {aka 'unsigned int *'}
     174 | extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
         |                            ~~~~~~~~~~^~~~~~~~
   cc1: some warnings being treated as errors


vim +/__div64_32 +199 include/asm-generic/div64.h

^1da177e4c3f41 Linus Torvalds     2005-04-16  176  
^1da177e4c3f41 Linus Torvalds     2005-04-16  177  /* The unnecessary pointer compare is there
^1da177e4c3f41 Linus Torvalds     2005-04-16  178   * to check for type safety (n must be 64bit)
^1da177e4c3f41 Linus Torvalds     2005-04-16  179   */
^1da177e4c3f41 Linus Torvalds     2005-04-16  180  # define do_div(n,base) ({				\
^1da177e4c3f41 Linus Torvalds     2005-04-16  181  	uint32_t __base = (base);			\
^1da177e4c3f41 Linus Torvalds     2005-04-16  182  	uint32_t __rem;					\
^1da177e4c3f41 Linus Torvalds     2005-04-16  183  	(void)(((typeof((n)) *)0) == ((uint64_t *)0));	\
911918aa7ef6f8 Nicolas Pitre      2015-11-02  184  	if (__builtin_constant_p(__base) &&		\
911918aa7ef6f8 Nicolas Pitre      2015-11-02  185  	    is_power_of_2(__base)) {			\
911918aa7ef6f8 Nicolas Pitre      2015-11-02  186  		__rem = (n) & (__base - 1);		\
911918aa7ef6f8 Nicolas Pitre      2015-11-02  187  		(n) >>= ilog2(__base);			\
c747ce4706190e Geert Uytterhoeven 2021-08-11  188  	} else if (__builtin_constant_p(__base) &&	\
461a5e51060c93 Nicolas Pitre      2015-10-30  189  		   __base != 0) {			\
461a5e51060c93 Nicolas Pitre      2015-10-30  190  		uint32_t __res_lo, __n_lo = (n);	\
461a5e51060c93 Nicolas Pitre      2015-10-30  191  		(n) = __div64_const32(n, __base);	\
461a5e51060c93 Nicolas Pitre      2015-10-30  192  		/* the remainder can be computed with 32-bit regs */ \
461a5e51060c93 Nicolas Pitre      2015-10-30  193  		__res_lo = (n);				\
461a5e51060c93 Nicolas Pitre      2015-10-30  194  		__rem = __n_lo - __res_lo * __base;	\
911918aa7ef6f8 Nicolas Pitre      2015-11-02  195  	} else if (likely(((n) >> 32) == 0)) {		\
^1da177e4c3f41 Linus Torvalds     2005-04-16  196  		__rem = (uint32_t)(n) % __base;		\
^1da177e4c3f41 Linus Torvalds     2005-04-16  197  		(n) = (uint32_t)(n) / __base;		\
c747ce4706190e Geert Uytterhoeven 2021-08-11  198  	} else {					\
^1da177e4c3f41 Linus Torvalds     2005-04-16 @199  		__rem = __div64_32(&(n), __base);	\
c747ce4706190e Geert Uytterhoeven 2021-08-11  200  	}						\
^1da177e4c3f41 Linus Torvalds     2005-04-16  201  	__rem;						\
^1da177e4c3f41 Linus Torvalds     2005-04-16  202   })
^1da177e4c3f41 Linus Torvalds     2005-04-16  203  

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