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| author | Josh Poimboeuf <jpoimboe@redhat.com> | 2020-04-28 16:45:16 -0500 |
|---|---|---|
| committer | Peter Zijlstra <peterz@infradead.org> | 2020-05-07 17:22:31 +0200 |
| commit | 1119d265bc20226c241e5540fc8a246d9e30b272 (patch) | |
| tree | 322ca3376268851548322f333f58160865366abe | |
| parent | 0e698dfa282211e414076f9dc7e83c1c288314fd (diff) | |
| download | linux-stable-1119d265bc20226c241e5540fc8a246d9e30b272.tar.gz linux-stable-1119d265bc20226c241e5540fc8a246d9e30b272.tar.bz2 linux-stable-1119d265bc20226c241e5540fc8a246d9e30b272.zip | |
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@linux.intel.com>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/378b51c9d9c894dc3294bc460b4b0869e950b7c5.1588110291.git.jpoimboe@redhat.com
| -rw-r--r-- | tools/objtool/check.c | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/tools/objtool/check.c b/tools/objtool/check.c index 4b170fd08a28..0e8f9a32e4d1 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; |