When resolving BTF ids, use the BTF in the module .BTF.base section
when passed the -B option. Both references to base BTF from split
BTF and BTF ids will be relocated for base vmlinux on module load.
Signed-off-by: Alan Maguire <alan.maguire@xxxxxxxxxx>
---
tools/bpf/resolve_btfids/main.c | 22 ++++++++++++++++++++--
1 file changed, 20 insertions(+), 2 deletions(-)
diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c
index d9520cb826b3..c5b622a31f18 100644
--- a/tools/bpf/resolve_btfids/main.c
+++ b/tools/bpf/resolve_btfids/main.c
@@ -115,6 +115,7 @@ struct object {
const char *path;
const char *btf;
const char *base_btf_path;
+ int base;
struct {
int fd;
@@ -532,11 +533,26 @@ static int symbols_resolve(struct object *obj)
__u32 nr_types;
if (obj->base_btf_path) {
- base_btf = btf__parse(obj->base_btf_path, NULL);
+ LIBBPF_OPTS(btf_parse_opts, optp);
+ const char *path;
+
+ if (obj->base) {
+ optp.btf_sec = BTF_BASE_ELF_SEC;
+ path = obj->path;
+ base_btf = btf__parse_opts(path, &optp);
+ /* fall back to normal base parsing if no BTF_BASE_ELF_SEC */
+ if (libbpf_get_error(base_btf))
+ base_btf = NULL;
+ }
+ if (!base_btf) {
+ optp.btf_sec = BTF_ELF_SEC;
+ path = obj->base_btf_path;
+ base_btf = btf__parse_opts(path, &optp);
+ }
err = libbpf_get_error(base_btf);
if (err) {
pr_err("FAILED: load base BTF from %s: %s\n",
- obj->base_btf_path, strerror(-err));
+ path, strerror(-err));
return -1;
}
}
@@ -781,6 +797,8 @@ int main(int argc, const char **argv)
"BTF data"),
OPT_STRING('b', "btf_base", &obj.base_btf_path, "file",
"path of file providing base BTF"),
+ OPT_INCR('B', "base", &obj.base,
+ "use " BTF_BASE_ELF_SEC " ELF section BTF as base"),
OPT_END()
};
int err = -1;
--
2.31.1
