[RFC][PATCH 1/6] objtool: Correctly handle retpoline thunk calls

[Peter Zijlstra]

Just like JMP handling, convert a direct CALL to a retpoline thunk
into a retpoline safe indirect CALL.

Signed-off-by: Peter Zijlstra (Intel) <pet...@infradead.org>
---
 tools/objtool/check.c |   12 ++++++++++++
 1 file changed, 12 insertions(+)

--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -953,6 +953,18 @@ static int add_call_destinations(struct
                                          dest_off);
                                return -1;
                        }
+
+               } else if (!strncmp(reloc->sym->name, "__x86_indirect_thunk_", 
21)) {
+                       /*
+                        * Retpoline calls are really dynamic calls in
+                        * disguise, so convert them accodingly.
+                        */
+                       insn->type = INSN_CALL_DYNAMIC;
+                       insn->retpoline_safe = true;
+
+                       remove_insn_ops(insn);
+                       continue;
+
                } else
                        insn->call_dest = reloc->sym;