diff options
| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2022-04-12 01:10:30 +0200 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2022-04-19 21:58:53 +0200 |
| commit | 26ff604102c98df79c3fe2614d1b9bb068d4c28c (patch) | |
| tree | 4c3819c8a1b45a04c4d4d5dfc30d473deb35b6e6 /tools/objtool/check.c | |
| parent | x86/uaccess: Don't jump between functions (diff) | |
| download | linux-26ff604102c98df79c3fe2614d1b9bb068d4c28c.tar.xz linux-26ff604102c98df79c3fe2614d1b9bb068d4c28c.zip | |
objtool: Don't set 'jump_dest' for sibling calls
For most sibling calls, 'jump_dest' is NULL because objtool treats the
jump like a call and sets 'call_dest'. But there are a few edge cases
where that's not true. Make it consistent to avoid unexpected behavior.
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/8737d6b9d1691831aed73375f444f0f42da3e2c9.1649718562.git.jpoimboe@redhat.com
Diffstat (limited to '')
| -rw-r--r-- | tools/objtool/check.c | 35 |
1 files changed, 22 insertions, 13 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index bd0c2c828940..6f492789c8c0 100644 --- a/tools/objtool/check.c +++ b/tools/objtool/check.c @@ -1271,7 +1271,7 @@ static bool is_first_func_insn(struct objtool_file *file, struct instruction *in */ static int add_jump_destinations(struct objtool_file *file) { - struct instruction *insn; + struct instruction *insn, *jump_dest; struct reloc *reloc; struct section *dest_sec; unsigned long dest_off; @@ -1291,7 +1291,10 @@ static int add_jump_destinations(struct objtool_file *file) add_retpoline_call(file, insn); continue; } else if (insn->func) { - /* internal or external sibling call (with reloc) */ + /* + * External sibling call or internal sibling call with + * STT_FUNC reloc. + */ add_call_dest(file, insn, reloc->sym, true); continue; } else if (reloc->sym->sec->idx) { @@ -1303,8 +1306,8 @@ static int add_jump_destinations(struct objtool_file *file) continue; } - insn->jump_dest = find_insn(file, dest_sec, dest_off); - if (!insn->jump_dest) { + jump_dest = find_insn(file, dest_sec, dest_off); + if (!jump_dest) { /* * This is a special case where an alt instruction @@ -1323,8 +1326,8 @@ static int add_jump_destinations(struct objtool_file *file) /* * Cross-function jump. */ - if (insn->func && insn->jump_dest->func && - insn->func != insn->jump_dest->func) { + if (insn->func && jump_dest->func && + insn->func != jump_dest->func) { /* * For GCC 8+, create parent/child links for any cold @@ -1342,16 +1345,22 @@ static int add_jump_destinations(struct objtool_file *file) * subfunction is through a jump table. */ if (!strstr(insn->func->name, ".cold") && - strstr(insn->jump_dest->func->name, ".cold")) { - insn->func->cfunc = insn->jump_dest->func; - insn->jump_dest->func->pfunc = insn->func; + strstr(jump_dest->func->name, ".cold")) { + insn->func->cfunc = jump_dest->func; + jump_dest->func->pfunc = insn->func; - } else if (!same_function(insn, insn->jump_dest) && - is_first_func_insn(file, insn->jump_dest)) { - /* internal sibling call (without reloc) */ - add_call_dest(file, insn, insn->jump_dest->func, true); + } else if (!same_function(insn, jump_dest) && + is_first_func_insn(file, jump_dest)) { + /* + * Internal sibling call without reloc or with + * STT_SECTION reloc. + */ + add_call_dest(file, insn, jump_dest->func, true); + continue; } } + + insn->jump_dest = jump_dest; } return 0; |