[PATCH v2 1/8] objtool: Don't report end of section error after an empty unwind hint

From: Josh Poimboeuf
Date: Mon Sep 18 2017 - 22:44:43 EST


If asm code specifies an UNWIND_HINT_EMPTY hint, don't warn if the
section ends unexpectedly. This can happen with the xen-head.S code
because the hypercall_page is "text" but it's all zeros.

Signed-off-by: Josh Poimboeuf <jpoimboe@xxxxxxxxxx>
---
tools/objtool/check.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index f744617c9946..d8683f0fe04d 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1737,11 +1737,14 @@ static int validate_branch(struct objtool_file *file, struct instruction *first,
if (insn->dead_end)
return 0;

- insn = next_insn;
- if (!insn) {
+ if (!next_insn) {
+ if (state.cfa.base == CFI_UNDEFINED)
+ return 0;
WARN("%s: unexpected end of section", sec->name);
return 1;
}
+
+ insn = next_insn;
}

return 0;
--
2.13.5