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Subject[PATCH] objtool: ignore INT3 padding
NOP padding doesn't count as unreachable instruction
neither should INT3.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
---

tools/objtool/arch.h | 3 ++-
tools/objtool/arch/x86/decode.c | 4 ++++
tools/objtool/check.c | 3 +++
3 files changed, 9 insertions(+), 1 deletion(-)

--- a/tools/objtool/arch.h
+++ b/tools/objtool/arch.h
@@ -34,7 +34,8 @@
#define INSN_BUG 9
#define INSN_NOP 10
#define INSN_OTHER 11
-#define INSN_LAST INSN_OTHER
+#define INSN_INT3 12
+#define INSN_LAST INSN_INT3

enum op_dest_type {
OP_DEST_REG,
--- a/tools/objtool/arch/x86/decode.c
+++ b/tools/objtool/arch/x86/decode.c
@@ -440,6 +440,10 @@ int arch_decode_instruction(struct elf *elf, struct section *sec,
*type = INSN_CONTEXT_SWITCH;
break;

+ case 0xcc:
+ *type = INSN_INT3;
+ break;
+
case 0xe8:
*type = INSN_CALL;
break;
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -1998,6 +1998,9 @@ static bool ignore_unreachable_insn(struct instruction *insn)

if (insn->ignore || insn->type == INSN_NOP)
return true;
+ /* Inter-function padding. */
+ if (insn->type == INSN_INT3)
+ return true;

/*
* Ignore any unused exceptions. This can happen when a whitelisted
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