3345193f6f
resolve_btfids prints a warning when it finds an unresolved symbol,
(id == 0) in id_patch. This can be the case for BTF sets that are empty
(due to disabled config options), hence printing warnings for certain
builds, most recently seen in [0].
The reason behind this is because id->cnt aliases id->id in btf_id
struct, leading to empty set showing up as ID 0 when we get to id_patch,
which triggers the warning. Since sets are an exception here, accomodate
by reusing hole in btf_id for bool is_set member, setting it to true for
BTF set when setting id->cnt, and use that to skip extraneous warning.
[0]: https://lore.kernel.org/all/1b99ae14-abb4-d18f-cc6a-d7e523b25542@gmail.com
Before:
; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko
adding symbol tcp_cubic_kfunc_ids
WARN: resolve_btfids: unresolved symbol tcp_cubic_kfunc_ids
patching addr 0: ID 0 [tcp_cubic_kfunc_ids]
sorting addr 4: cnt 0 [tcp_cubic_kfunc_ids]
update ok for net/ipv4/tcp_cubic.ko
After:
; ./tools/bpf/resolve_btfids/resolve_btfids -v -b vmlinux net/ipv4/tcp_cubic.ko
adding symbol tcp_cubic_kfunc_ids
patching addr 0: ID 0 [tcp_cubic_kfunc_ids]
sorting addr 4: cnt 0 [tcp_cubic_kfunc_ids]
update ok for net/ipv4/tcp_cubic.ko
Fixes:
|
||
|---|---|---|
| .. | ||
| bpftool | ||
| resolve_btfids | ||
| runqslower | ||
| .gitignore | ||
| Makefile | ||
| bpf_asm.c | ||
| bpf_dbg.c | ||
| bpf_exp.l | ||
| bpf_exp.y | ||
| bpf_jit_disasm.c | ||