1 files changed, 22 insertions, 0 deletions

diff --git a/tools/objtool/check.c b/tools/objtool/check.c
index 3a31b238f885..38047c6aa575 100644
--- a/tools/objtool/check.c
+++ b/tools/objtool/check.c
@@ -543,6 +543,28 @@ static int add_jump_destinations(struct objtool_file *file)
                                   dest_off);
                         return -1;
                 }
+
+                /*
+                 * For GCC 8+, create parent/child links for any cold
+                 * subfunctions.  This is _mostly_ redundant with a similar
+                 * initialization in read_symbols().
+                 *
+                 * If a function has aliases, we want the *first* such function
+                 * in the symbol table to be the subfunction's parent.  In that
+                 * case we overwrite the initialization done in read_symbols().
+                 *
+                 * However this code can't completely replace the
+                 * read_symbols() code because this doesn't detect the case
+                 * where the parent function's only reference to a subfunction
+                 * is through a switch table.
+                 */
+                if (insn->func && insn->jump_dest->func &&
+                    insn->func != insn->jump_dest->func &&
+                    !strstr(insn->func->name, ".cold.") &&
+                    strstr(insn->jump_dest->func->name, ".cold.")) {
+                        insn->func->cfunc = insn->jump_dest->func;
+                        insn->jump_dest->func->pfunc = insn->func;
+                }
         }
 
         return 0;