Re: [djiang:cxl/fwctl 13/25] drivers/cxl/cxlmem.h:798:44: error: 'counted_by' argument must be a simple declaration reference

Re: [djiang:cxl/fwctl 13/25] drivers/cxl/cxlmem.h:798:44: error: 'counted_by' argument must be a simple declaration reference

[Nathan Chancellor]

On Fri, Sep 27, 2024 at 09:39:54AM +0800, kernel test robot wrote:
> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/djiang/linux.git cxl/fwctl
> head:   b4f2900f53c72de8fc639b62e44763c6a9695d3b
> commit: 5a0496c19151d83cd0d926f8a1488eeaab27509b [13/25] cxl: Add Get Supported Features command for kernel usage
> config: arm-randconfig-004-20240927 (https://download.01.org/0day-ci/archive/20240927/202409270908.NJPL38kw-lkp@intel.com/config)
> compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 7773243d9916f98ba0ffce0c3a960e4aa9f03e81)
> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240927/202409270908.NJPL38kw-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/202409270908.NJPL38kw-lkp@intel.com/
> 
> All errors (new ones prefixed by >>):
> 
>    In file included from drivers/cxl/port.c:7:
>    In file included from drivers/cxl/cxlmem.h:6:
>    In file included from include/linux/pci.h:1646:
>    In file included from include/linux/dmapool.h:14:
>    In file included from include/linux/scatterlist.h:8:
>    In file included from include/linux/mm.h:2232:
>    include/linux/vmstat.h:517:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
>      517 |         return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
>          |                               ~~~~~~~~~~~ ^ ~~~
>    In file included from drivers/cxl/port.c:7:
> >> drivers/cxl/cxlmem.h:798:44: error: 'counted_by' argument must be a simple declaration reference
>      798 |         struct cxl_feat_entry ents[] __counted_by(le32_to_cpu(supported_feats));
>          |                                      ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

It seems like this should likely use the __counted_by_le() macro so that
it is only used for tracking on little endian targets?

>    include/linux/byteorder/generic.h:89:21: note: expanded from macro 'le32_to_cpu'
>       89 | #define le32_to_cpu __le32_to_cpu
>          |                     ^
>    include/uapi/linux/byteorder/little_endian.h:35:26: note: expanded from macro '__le32_to_cpu'
>       35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
>          |                          ^
>    include/linux/compiler_attributes.h:105:62: note: expanded from macro '__counted_by'
>      105 | # define __counted_by(member)           __attribute__((__counted_by__(member)))
>          |                                                                       ^~~~~~
>    1 warning and 1 error generated.
> 
> 
> vim +/counted_by +798 drivers/cxl/cxlmem.h
> 
>    793	
>    794	struct cxl_mbox_get_sup_feats_out {
>    795		__le16 num_entries;
>    796		__le16 supported_feats;
>    797		u8 reserved[4];
>  > 798		struct cxl_feat_entry ents[] __counted_by(le32_to_cpu(supported_feats));
>    799	} __packed;
>    800	
> 
> -- 
> 0-DAY CI Kernel Test Service
> https://github.com/intel/lkp-tests/wiki
> 

Re: [djiang:cxl/fwctl 13/25] drivers/cxl/cxlmem.h:798:44: error: 'counted_by' argument must be a simple declaration reference

[Dave Jiang]

On 9/27/24 6:41 AM, Nathan Chancellor wrote:
> On Fri, Sep 27, 2024 at 09:39:54AM +0800, kernel test robot wrote:
>> tree:   https://git.kernel.org/pub/scm/linux/kernel/git/djiang/linux.git cxl/fwctl
>> head:   b4f2900f53c72de8fc639b62e44763c6a9695d3b
>> commit: 5a0496c19151d83cd0d926f8a1488eeaab27509b [13/25] cxl: Add Get Supported Features command for kernel usage
>> config: arm-randconfig-004-20240927 (https://download.01.org/0day-ci/archive/20240927/202409270908.NJPL38kw-lkp@intel.com/config)
>> compiler: clang version 20.0.0git (https://github.com/llvm/llvm-project 7773243d9916f98ba0ffce0c3a960e4aa9f03e81)
>> reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20240927/202409270908.NJPL38kw-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/202409270908.NJPL38kw-lkp@intel.com/
>>
>> All errors (new ones prefixed by >>):
>>
>>    In file included from drivers/cxl/port.c:7:
>>    In file included from drivers/cxl/cxlmem.h:6:
>>    In file included from include/linux/pci.h:1646:
>>    In file included from include/linux/dmapool.h:14:
>>    In file included from include/linux/scatterlist.h:8:
>>    In file included from include/linux/mm.h:2232:
>>    include/linux/vmstat.h:517:36: warning: arithmetic between different enumeration types ('enum node_stat_item' and 'enum lru_list') [-Wenum-enum-conversion]
>>      517 |         return node_stat_name(NR_LRU_BASE + lru) + 3; // skip "nr_"
>>          |                               ~~~~~~~~~~~ ^ ~~~
>>    In file included from drivers/cxl/port.c:7:
>>>> drivers/cxl/cxlmem.h:798:44: error: 'counted_by' argument must be a simple declaration reference
>>      798 |         struct cxl_feat_entry ents[] __counted_by(le32_to_cpu(supported_feats));
>>          |                                      ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> 
> It seems like this should likely use the __counted_by_le() macro so that
> it is only used for tracking on little endian targets?

Thank you! That helped address the issue.

> 
>>    include/linux/byteorder/generic.h:89:21: note: expanded from macro 'le32_to_cpu'
>>       89 | #define le32_to_cpu __le32_to_cpu
>>          |                     ^
>>    include/uapi/linux/byteorder/little_endian.h:35:26: note: expanded from macro '__le32_to_cpu'
>>       35 | #define __le32_to_cpu(x) ((__force __u32)(__le32)(x))
>>          |                          ^
>>    include/linux/compiler_attributes.h:105:62: note: expanded from macro '__counted_by'
>>      105 | # define __counted_by(member)           __attribute__((__counted_by__(member)))
>>          |                                                                       ^~~~~~
>>    1 warning and 1 error generated.
>>
>>
>> vim +/counted_by +798 drivers/cxl/cxlmem.h
>>
>>    793	
>>    794	struct cxl_mbox_get_sup_feats_out {
>>    795		__le16 num_entries;
>>    796		__le16 supported_feats;
>>    797		u8 reserved[4];
>>  > 798		struct cxl_feat_entry ents[] __counted_by(le32_to_cpu(supported_feats));
>>    799	} __packed;
>>    800	
>>
>> -- 
>> 0-DAY CI Kernel Test Service
>> https://github.com/intel/lkp-tests/wiki
>>