On Thu, Aug 20, 2020 at 2:53 PM Alexei Starovoitov
[off-list ref] wrote:

Why did you choose to do it during main do_check() walk instead of this pre-pass ?
check_ld_imm() can be called multiple times for the same insn,
so it's faster and less surprising to do it during replace_map_fd_with_map_ptr().
BTF needs to be parsed first, of course.
You can either move check_btf_info() before replace_map_fd_with_map_ptr() or
move replace_map_fd_with_map_ptr() after check_btf_info().
The latter is probably cleaner.

Ah, that does make more sense. I can move
replace_map_fd_with_map_ptr() after check_btf_info() (or
check_attach_btf_id()) and rename it to better reflect the fact that
it's not just for maps now.

Thanks for the insights!
Hao