diff --git a/qa/config/crimson_qa_overrides.yaml b/qa/config/crimson_qa_overrides.yaml
index 37f176db0a1c4..8cf98f3800167 100644
--- a/qa/config/crimson_qa_overrides.yaml
+++ b/qa/config/crimson_qa_overrides.yaml
@@ -10,6 +10,7 @@ overrides:
       osd:
         crimson osd obc lru size: 10
         debug alienstore: 20
+        debug ms: 20
     flavor: crimson
   workunit:
     env:
diff --git a/src/crimson/net/io_handler.cc b/src/crimson/net/io_handler.cc
index b93124f3c1269..bc5e9bf404c59 100644
--- a/src/crimson/net/io_handler.cc
+++ b/src/crimson/net/io_handler.cc
@@ -347,7 +347,7 @@ void IOHandler::do_set_io_state(
 {
   ceph_assert_always(seastar::this_shard_id() == get_shard_id());
   auto prv_state = get_io_state();
-  logger().debug("{} got {}do_set_io_state(): prv_state={}, new_state={}, "
+  logger().debug("{} got {} do_set_io_state(): prv_state={}, new_state={}, "
                  "fa={}, set_notify_out={}, at {}",
                  conn,
                  cc_seq.has_value() ? fmt::format("{} ", *cc_seq) : "",
@@ -984,7 +984,7 @@ void IOHandler::notify_out_dispatch()
       });
     });
   }
-  if (shard_states->try_enter_out_dispatching()) {
+  if (shard_states->try_enter_out_dispatching(conn)) {
     shard_states->dispatch_in_background(
         "do_out_dispatch", conn, [this] {
       return do_out_dispatch(*shard_states);
diff --git a/src/crimson/net/io_handler.h b/src/crimson/net/io_handler.h
index 5986fcb16ac28..41c76ab925b84 100644
--- a/src/crimson/net/io_handler.h
+++ b/src/crimson/net/io_handler.h
@@ -309,7 +309,7 @@ class IOHandler final : public ConnectionHandler {
       in_exit_dispatching = std::nullopt;
     }
 
-    bool try_enter_out_dispatching() {
+    bool try_enter_out_dispatching(SocketConnection &conn) {
       assert(seastar::this_shard_id() == sid);
       if (out_dispatching) {
         // already dispatching out
@@ -327,6 +327,9 @@ class IOHandler final : public ConnectionHandler {
         // do not dispatch out
         return false;
       default:
+        crimson::get_logger(ceph_subsys_ms).error(
+          "{} try_enter_out_dispatching() got wrong io_state {}",
+          conn, io_state);
         ceph_abort("impossible");
       }
     }
@@ -574,6 +577,8 @@ struct fmt::formatter<crimson::net::IOHandler::io_state_t>
     case switched:
       name = "switched";
       break;
+    default:
+      name = "undefined";
     }
     return formatter<string_view>::format(name, ctx);
   }