Re: [RFC] btf: split core BTF parsing out of BPF subsystem into kernel/btf/

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

Hi Sasha,

[This is a private test report for your RFC patch.]
kernel test robot noticed the following build errors:

[auto build test ERROR on bpf-next/master]
[also build test ERROR on bpf/master akpm-mm/mm-nonmm-unstable linus/master v7.0-rc5]
[cannot apply to bpf-next/net next-20260327]
[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/Sasha-Levin/btf-split-core-BTF-parsing-out-of-BPF-subsystem-into-kernel-btf/20260327-005818
base:   https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next.git master
patch link:    https://lore.kernel.org/r/20260325011853.657295-1-sashal%40kernel.org
patch subject: [RFC] btf: split core BTF parsing out of BPF subsystem into kernel/btf/
config: sh-allyesconfig (https://download.01.org/0day-ci/archive/20260329/202603290444.9kNP6afH-lkp@intel.com/config)
compiler: sh4-linux-gcc (GCC) 15.2.0
reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20260329/202603290444.9kNP6afH-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/202603290444.9kNP6afH-lkp@intel.com/

All errors (new ones prefixed by >>):

   In file included from kernel/bpf/btf_relocate.c:2:
   kernel/bpf/../../tools/lib/bpf/btf_relocate.c: In function 'btf_relocate_rewrite_strs':
>> kernel/bpf/../../tools/lib/bpf/btf_relocate.c:20:49: error: implicit declaration of function 'btf_str_by_offset'; did you mean 'btf__str_by_offset'? [-Wimplicit-function-declaration]
      20 | #define btf__str_by_offset                      btf_str_by_offset
         |                                                 ^~~~~~~~~~~~~~~~~
   include/linux/printk.h:483:33: note: in expansion of macro 'btf__str_by_offset'
     483 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
         |                                 ^~~~~~~~~~~
   include/linux/printk.h:511:26: note: in expansion of macro 'printk_index_wrap'
     511 | #define printk(fmt, ...) printk_index_wrap(_printk, fmt, ##__VA_ARGS__)
         |                          ^~~~~~~~~~~~~~~~~
   include/linux/printk.h:564:9: note: in expansion of macro 'printk'
     564 |         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
         |         ^~~~~~
   kernel/bpf/../../tools/lib/bpf/btf_relocate.c:431:33: note: in expansion of macro 'pr_warn'
     431 |                                 pr_warn("string '%s' [offset %u] is not mapped to base BTF\n",
         |                                 ^~~~~~~
   In file included from include/asm-generic/bug.h:31,
                    from arch/sh/include/asm/bug.h:112,
                    from include/linux/bug.h:5,
                    from include/linux/alloc_tag.h:8,
                    from include/linux/workqueue.h:9,
                    from include/linux/bpf.h:11,
                    from kernel/bpf/../../tools/lib/bpf/btf_relocate.c:9:
   include/linux/kern_levels.h:5:25: warning: format '%s' expects argument of type 'char *', but argument 2 has type 'int' [-Wformat=]
       5 | #define KERN_SOH        "\001"          /* ASCII Start Of Header */
         |                         ^~~~~~
   include/linux/printk.h:483:25: note: in definition of macro 'printk_index_wrap'
     483 |                 _p_func(_fmt, ##__VA_ARGS__);                           \
         |                         ^~~~
   include/linux/printk.h:564:9: note: in expansion of macro 'printk'
     564 |         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
         |         ^~~~~~
   include/linux/kern_levels.h:12:25: note: in expansion of macro 'KERN_SOH'
      12 | #define KERN_WARNING    KERN_SOH "4"    /* warning conditions */
         |                         ^~~~~~~~
   include/linux/printk.h:564:16: note: in expansion of macro 'KERN_WARNING'
     564 |         printk(KERN_WARNING pr_fmt(fmt), ##__VA_ARGS__)
         |                ^~~~~~~~~~~~
   kernel/bpf/../../tools/lib/bpf/btf_relocate.c:431:33: note: in expansion of macro 'pr_warn'
     431 |                                 pr_warn("string '%s' [offset %u] is not mapped to base BTF\n",
         |                                 ^~~~~~~


vim +20 kernel/bpf/../../tools/lib/bpf/btf_relocate.c

8646db238997df3 Alan Maguire 2024-06-20  15  
8646db238997df3 Alan Maguire 2024-06-20  16  #define btf_type_by_id				(struct btf_type *)btf_type_by_id
8646db238997df3 Alan Maguire 2024-06-20  17  #define btf__type_cnt				btf_nr_types
8646db238997df3 Alan Maguire 2024-06-20  18  #define btf__base_btf				btf_base_btf
8646db238997df3 Alan Maguire 2024-06-20  19  #define btf__name_by_offset			btf_name_by_offset
8646db238997df3 Alan Maguire 2024-06-20 @20  #define btf__str_by_offset			btf_str_by_offset
8646db238997df3 Alan Maguire 2024-06-20  21  #define btf_kflag				btf_type_kflag
8646db238997df3 Alan Maguire 2024-06-20  22  

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