fix(modbus): dispose the previous transport and probe loops on re-initialize

2026-08-15 21:37:28 -04:00
parent dc459633e0
commit c3970a2e5d
2 changed files with 111 additions and 0 deletions
@@ -255,6 +255,30 @@ public sealed class ModbusDriver
        WriteHealth(new DriverHealth(DriverState.Initializing, null, null));
        try
        {
+            // Release whatever a PREVIOUS initialize published before building the replacements. All
+            // three fields assigned below (_transport, _probeCts, _reprobeCts) were simply overwritten,
+            // so a second initialize on a live driver stranded a connected transport plus two running
+            // background loops that no later dispose could reach. Reachable without any teardown of
+            // ours: DriverInstanceActor re-runs InitializeAsync with no ShutdownAsync when an ApplyDelta
+            // lands while the driver is in Connecting/Reconnecting (AdoptConfigDuringInit).
+            // Deliberately NOT the shared TeardownAsync(): that also disposes _poll, the PollGroupEngine
+            // constructed once in the ctor and never rebuilt, which would leave the re-initialized
+            // driver unable to serve subscriptions. A first initialize sees three nulls, so this is a
+            // no-op on the initial call.
+            try { _probeCts?.Cancel(); } catch { }
+            _probeCts?.Dispose();
+            _probeCts = null;
+
+            try { _reprobeCts?.Cancel(); } catch { }
+            _reprobeCts?.Dispose();
+            _reprobeCts = null;
+
+            if (_transport is not null)
+            {
+                await _transport.DisposeAsync().ConfigureAwait(false);
+                _transport = null;
+            }
+
            // #516: re-parse the supplied DriverConfig so a config change delivered through the IDriver
            // contract is honoured. Without this the driver keeps serving the options it was CONSTRUCTED
            // with, so an operator's edit is discarded while the deployment still seals green. An empty /