Merge tag 'powerpc-5.9-3' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc...

[linux-2.6-microblaze.git] / tools / bpf / resolve_btfids / main.c

diff --git a/tools/bpf/resolve_btfids/main.c b/tools/bpf/resolve_btfids/main.c
index 4d9ecb9..0def0bb 100644 (file)
--- a/tools/bpf/resolve_btfids/main.c
+++ b/tools/bpf/resolve_btfids/main.c
@@ -233,6 +233,39 @@ static struct btf_id *add_symbol(struct rb_root *root, char *name, size_t size)
        return btf_id__add(root, id, false);
 }
 
+/*
+ * The data of compressed section should be aligned to 4
+ * (for 32bit) or 8 (for 64 bit) bytes. The binutils ld
+ * sets sh_addralign to 1, which makes libelf fail with
+ * misaligned section error during the update:
+ *    FAILED elf_update(WRITE): invalid section alignment
+ *
+ * While waiting for ld fix, we fix the compressed sections
+ * sh_addralign value manualy.
+ */
+static int compressed_section_fix(Elf *elf, Elf_Scn *scn, GElf_Shdr *sh)
+{
+       int expected = gelf_getclass(elf) == ELFCLASS32 ? 4 : 8;
+
+       if (!(sh->sh_flags & SHF_COMPRESSED))
+               return 0;
+
+       if (sh->sh_addralign == expected)
+               return 0;
+
+       pr_debug2(" - fixing wrong alignment sh_addralign %u, expected %u\n",
+                 sh->sh_addralign, expected);
+
+       sh->sh_addralign = expected;
+
+       if (gelf_update_shdr(scn, sh) == 0) {
+               printf("FAILED cannot update section header: %s\n",
+                       elf_errmsg(-1));
+               return -1;
+       }
+       return 0;
+}
+
 static int elf_collect(struct object *obj)
 {
        Elf_Scn *scn = NULL;
@@ -309,6 +342,9 @@ static int elf_collect(struct object *obj)
                        obj->efile.idlist_shndx = idx;
                        obj->efile.idlist_addr  = sh.sh_addr;
                }
+
+               if (compressed_section_fix(elf, scn, &sh))
+                       return -1;
        }
 
        return 0;