summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorJosh Poimboeuf <jpoimboe@redhat.com>2022-04-11 16:10:30 -0700
committerPeter Zijlstra <peterz@infradead.org>2022-04-19 21:58:53 +0200
commit26ff604102c98df79c3fe2614d1b9bb068d4c28c (patch)
tree4c3819c8a1b45a04c4d4d5dfc30d473deb35b6e6
parent02041b32256628aef0d18ec15d3658fe41bc1afe (diff)
downloadlinux-26ff604102c98df79c3fe2614d1b9bb068d4c28c.tar.bz2
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
-rw-r--r--tools/objtool/check.c35
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;