From aea11d53a8066fed2a1302394645d1a2a20d1a4e Mon Sep 17 00:00:00 2001
From: Jitendra Bhurat <jbhurat@gmail.com>
Date: Thu, 13 Dec 2018 12:31:50 -0500
Subject: [PATCH] calling unlock using defer, preventing deadlock when
 miner.setEtherbase() returns an error

---
 eth/backend.go | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/eth/backend.go b/eth/backend.go
index 44ebc6e2d..e401242a2 100644
--- a/eth/backend.go
+++ b/eth/backend.go
@@ -356,12 +356,13 @@ func (s *Ethereum) Etherbase() (eb common.Address, err error) {
 // set in js console via admin interface or wrapper from cli flags
 func (s *Ethereum) SetEtherbase(etherbase common.Address) {
 	s.lock.Lock()
+	defer s.lock.Unlock()
 	if _, ok := s.engine.(consensus.Istanbul); ok {
 		log.Error("Cannot set etherbase in Istanbul consensus")
 		return
 	}
 	s.etherbase = etherbase
-	s.lock.Unlock()
+
 
 	s.miner.SetEtherbase(etherbase)
 }