From 632fd36205b4be59417bc152bcc0fc6f305c2b03 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Magiera?= <magik6k@gmail.com>
Date: Thu, 13 Aug 2020 12:17:24 +0200
Subject: [PATCH] sealing sched: Fix deadlock in worker watcher

---
 extern/sector-storage/sched_watch.go | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/extern/sector-storage/sched_watch.go b/extern/sector-storage/sched_watch.go
index d93cf1af3..2dd9875d7 100644
--- a/extern/sector-storage/sched_watch.go
+++ b/extern/sector-storage/sched_watch.go
@@ -87,11 +87,14 @@ func (sh *scheduler) runWorkerWatcher() {
 			}
 
 			log.Warnf("worker %d dropped", wid)
-			select {
-			case sh.workerClosing <- wid:
-			case <-sh.closing:
-				return
-			}
+			// send in a goroutine to avoid a deadlock between workerClosing / watchClosing
+			go func() {
+				select {
+				case sh.workerClosing <- wid:
+				case <-sh.closing:
+					return
+				}
+			}()
 		}
 	}
 }