The following commit has been merged into the objtool/urgent branch of tip:
Commit-ID: 1119d265bc20226c241e5540fc8a246d9e30b272
Gitweb: https://git.kernel.org/tip/1119d265bc20226c241e5540fc8a246d9e30b272
Author: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
AuthorDate: Tue, 28 Apr 2020 16:45:16 -05:00
Committer: Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Thu, 07 May 2020 17:22:31 +02:00
objtool: Fix infinite loop in find_jump_table()
Kristen found a hang in objtool when building with -ffunction-sections.
It was caused by evergreen_pcie_gen2_enable.cold() being laid out
immediately before evergreen_pcie_gen2_enable(). Since their "pfunc" is
always the same, find_jump_table() got into an infinite loop because it
didn't recognize the boundary between the two functions.
Fix that with a new prev_insn_same_sym() helper, which doesn't cross
subfunction boundaries.
Reported-by: Kristen Carlson Accardi <kristen@xxxxxxxxxxxxxxx>
Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Link: https://lkml.kernel.org/r/378b51c9d9c894dc3294bc460b4b0869e950b7c5.1588110291.git.jpoimboe@xxxxxxxxxx
---
tools/objtool/check.c | 15 +++++++++++++--
1 file changed, 13 insertions(+), 2 deletions(-)
diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 4b170fd..0e8f9a3 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -72,6 +72,17 @@ static struct instruction *next_insn_same_func(struct objtool_file *file,
return find_insn(file, func->cfunc->sec, func->cfunc->offset);
}
+static struct instruction *prev_insn_same_sym(struct objtool_file *file,
+ struct instruction *insn)
+{
+ struct instruction *prev = list_prev_entry(insn, list);
+
+ if (&prev->list != &file->insn_list && prev->func == insn->func)
+ return prev;
+
+ return NULL;
+}
+
#define func_for_each_insn(file, func, insn) \
for (insn = find_insn(file, func->sec, func->offset); \
insn; \
@@ -1050,8 +1061,8 @@ static struct rela *find_jump_table(struct objtool_file *file,
* it.
*/
for (;
- &insn->list != &file->insn_list && insn->func && insn->func->pfunc == func;
- insn = insn->first_jump_src ?: list_prev_entry(insn, list)) {
+ insn && insn->func && insn->func->pfunc == func;
+ insn = insn->first_jump_src ?: prev_insn_same_sym(file, insn)) {
if (insn != orig_insn && insn->type == INSN_JUMP_DYNAMIC)
break;
|