When walking backward to find the base address of a switch table,
also take into account conditionnal branches and dynamic jumps from
a previous switch table.
To avoid mis-routing, break when stumbling on a function return.
Signed-off-by: Christophe Leroy <christophe.le...@csgroup.eu>
---
tools/objtool/check.c | 8 ++++++--
1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 361c832aefc8..ea0945f2195f 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -2034,6 +2034,8 @@ static int add_jump_table(struct objtool_file *file,
struct instruction *insn,
alt->next = insn->alts;
insn->alts = alt;
prev_offset = reloc_offset(reloc);
+ if (!dest_insn->first_jump_src)
+ dest_insn->first_jump_src = insn;
}
if (!prev_offset) {
@@ -2068,6 +2070,9 @@ static struct reloc *find_jump_table(struct objtool_file
*file,
insn->gpr == orig_insn->gpr)
break;
+ if (insn->type == INSN_RETURN)
+ break;
+
/* allow small jumps within the range */
if (insn->type == INSN_JUMP_UNCONDITIONAL &&
insn->jump_dest &&
@@ -2130,8 +2135,7 @@ static int mark_add_func_jump_tables(struct objtool_file
*file,
* that find_jump_table() can back-track using those and
* avoid some potentially confusing code.
*/
- if (insn->type == INSN_JUMP_UNCONDITIONAL && insn->jump_dest &&
- insn->offset > last->offset &&
+ if (is_static_jump(insn) && insn->jump_dest &&
insn->jump_dest->offset > insn->offset &&
!insn->jump_dest->first_jump_src) {
--
2.41.0
