On Mon, Feb 22, 2021 at 5:20 PM Kun-Chuan Hsieh jetswayss@gmail.com wrote:
Older versions of libelf cannot recognize the compressed section. However, it's only required to fix the compressed section info when compiling with CONFIG_DEBUG_INFO_COMPRESSED flag is set.
Is it possible to detect (at compilation time or at run time) if libelf supports compressed ELF sections instead?
Only compile the compressed_section_fix function when necessary will make it easier to enable the BTF function. Since the tool resolve_btfids is compiled with host toolchain. The host toolchain might be older than the cross compile toolchain.
Cc: stable@vger.kernel.org Signed-off-by: Kun-Chuan Hsieh jetswayss@gmail.com
tools/bpf/resolve_btfids/main.c | 4 ++++ 1 file changed, 4 insertions(+)
diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c index 7409d7860aa6..ad40346c6631 100644 --- a/tools/bpf/resolve_btfids/main.c +++ b/tools/bpf/resolve_btfids/main.c @@ -260,6 +260,7 @@ static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size) return btf_id__add(root, id, false); }
+#ifdef CONFIG_DEBUG_INFO_COMPRESSED /*
- The data of compressed section should be aligned to 4
- (for 32bit) or 8 (for 64 bit) bytes. The binutils ld
@@ -292,6 +293,7 @@ static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh) } return 0; } +#endif
static int elf_collect(struct object *obj) { @@ -370,8 +372,10 @@ static int elf_collect(struct object *obj) obj->efile.idlist_addr = sh.sh_addr; }
+#ifdef CONFIG_DEBUG_INFO_COMPRESSED if (compressed_section_fix(elf, scn, &sh)) return -1; +#endif }
return 0;-- 2.25.1