Currently, libbpf considers a single routine in .text as a program. This
is particularly confusing when it comes to library objects - a single routine
meant to be used as an extern will instead be considered a bpf_program.
This patch hides this compatibility behavior behind a libbpf_mode strict
mode flag.
Signed-off-by: Delyan Kratunov <delyank@xxxxxx>
---
tools/lib/bpf/libbpf.c | 7 +++++++
tools/lib/bpf/libbpf_legacy.h | 6 ++++++
2 files changed, 13 insertions(+)
diff --git a/tools/lib/bpf/libbpf.c b/tools/lib/bpf/libbpf.c
index 43161fdd44bb..b6f11ce0d6bc 100644
--- a/tools/lib/bpf/libbpf.c
+++ b/tools/lib/bpf/libbpf.c
@@ -3832,7 +3832,14 @@ static bool prog_is_subprog(const struct bpf_object *obj,
* .text programs are subprograms (even if they are not called from
* other programs), because libbpf never explicitly supported mixing
* SEC()-designated BPF programs and .text entry-point BPF programs.
+ *
+ * In libbpf 1.0 strict mode, we always consider .text
+ * programs to be subprograms.
*/
+
+ if (libbpf_mode & LIBBPF_STRICT_TEXT_ONLY_SUBPROGRAMS)
+ return prog->sec_idx == obj->efile.text_shndx;
+
return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1;
}
diff --git a/tools/lib/bpf/libbpf_legacy.h b/tools/lib/bpf/libbpf_legacy.h
index a283cf031665..388384ea97a7 100644
--- a/tools/lib/bpf/libbpf_legacy.h
+++ b/tools/lib/bpf/libbpf_legacy.h
@@ -78,6 +78,12 @@ enum libbpf_strict_mode {
* in favor of BTF-defined map definitions in SEC(".maps").
*/
LIBBPF_STRICT_MAP_DEFINITIONS = 0x20,
+ /*
+ * When enabled, always consider routines in the .text section to
+ * be sub-programs. Previously, single routines in the .text section
+ * would be considered a program on their own.
+ */
+ LIBBPF_STRICT_TEXT_ONLY_SUBPROGRAMS = 0x40,
__LIBBPF_STRICT_LAST,
};
--
2.34.1
