Hi Andrii,

First bad commit (maybe != root cause):

tree:   https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git master
head:   7426cedc7dad67bf3c71ea6cc29ab7822e1a453f
commit: f2644fb44de9abd54e57b55f584c7c67526f7c02 selftests/bpf: Add function linking selftest
date:   9 weeks ago
config: x86_64-rhel-8.3-kselftests (attached as .config)
compiler: gcc-9 (Debian 9.3.0-22) 9.3.0
reproduce (this is a W=1 build):
        # https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=f2644fb44de9abd54e57b55f584c7c67526f7c02
        git remote add linus https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
        git fetch --no-tags linus master
        git checkout f2644fb44de9abd54e57b55f584c7c67526f7c02
        # save the attached .config to linux build tree
        make W=1 ARCH=x86_64 

If you fix the issue, kindly add following tag as appropriate
Reported-by: kernel test robot <lkp@intel.com>

All errors (new ones prefixed by >>):

   libbpf: failed to find BTF info for global/extern symbol 'my_tid'
>> Error: failed to link '/no_alu32/linked_funcs1.o': Unknown error -2 (-2)

---
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