diff --git a/cmd/olliesrv/server.go b/cmd/olliesrv/server.go
index 392fbca..c1ac51c 100644
--- a/cmd/olliesrv/server.go
+++ b/cmd/olliesrv/server.go
@@ -606,46 +606,47 @@ func read(root *fs.Tree, cs *connState, fc *plan9.Fcall, ctx context.Context) *p
 			// lives until the client disconnects or clunks the fid
 			clientConnCtx := cs.ctx
 			cs.mu.RUnlock()
-			if fidOK {
+			if !fidOK {
+				return errFcall(fc, "bad fid")
+			}
+			f.mu.Lock()
+			filter := f.eventFilter
+			eventCh := f.eventCh
+			f.mu.Unlock()
+
+			// Create subscription on first read (filter defaults to "*" for all events)
+			if eventCh == nil {
+				if filter == "" {
+					filter = "*"
+				}
+				subCtx, cancel := context.WithCancel(clientConnCtx)
+				ch := session.SubscribeEventsFiltered(subCtx, filter)
 				f.mu.Lock()
-				filter := f.eventFilter
-				eventCh := f.eventCh
+				f.eventFilter = filter
+				f.eventCh = ch
+				f.eventCancel = cancel
 				f.mu.Unlock()
+				eventCh = ch
+			}
 
-				// Create subscription on first read (filter defaults to "*" for all events)
-				if eventCh == nil {
-					if filter == "" {
-						filter = "*"
-					}
-					subCtx, cancel := context.WithCancel(clientConnCtx)
-					ch := session.SubscribeEventsFiltered(subCtx, filter)
-					f.mu.Lock()
-					f.eventFilter = filter
-					f.eventCh = ch
-					f.eventCancel = cancel
-					f.mu.Unlock()
-					eventCh = ch
+			// Read from subscription — blocks until event arrives
+			select {
+			case ev, ok := <-eventCh:
+				if !ok {
+					return &plan9.Fcall{Type: plan9.Rread, Tag: fc.Tag, Count: 0}
 				}
-
-				// Read from subscription — blocks until event arrives
-				select {
-				case ev, ok := <-eventCh:
-					if !ok {
-						return &plan9.Fcall{Type: plan9.Rread, Tag: fc.Tag, Count: 0}
-					}
-					line := ev.Topic
-					if ev.Payload != "" {
-						line += " " + ev.Payload
-					}
-					content := []byte(line + "\n")
-					count := int(fc.Count)
-					if count > len(content) {
-						count = len(content)
-					}
-					return &plan9.Fcall{Type: plan9.Rread, Tag: fc.Tag, Count: uint32(count), Data: content[:count]}
-				case <-ctx.Done():
-					return errFcall(fc, "interrupted")
+				line := ev.Topic
+				if ev.Payload != "" {
+					line += " " + ev.Payload
 				}
+				content := []byte(line + "\n")
+				count := int(fc.Count)
+				if count > len(content) {
+					count = len(content)
+				}
+				return &plan9.Fcall{Type: plan9.Rread, Tag: fc.Tag, Count: uint32(count), Data: content[:count]}
+			case <-ctx.Done():
+				return errFcall(fc, "interrupted")
 			}
 		}