diff --git a/src/runtime/proc.go b/src/runtime/proc.go
index 6e56b4b1d1..b5e27c3e02 100644
--- a/src/runtime/proc.go
+++ b/src/runtime/proc.go
@@ -1013,7 +1013,7 @@ func stopTheWorldWithSema() {
 	}
 
 	lock(&sched.lock)
-	sched.stopwait = gomaxprocs
+	sched.stopwait = uint32(gomaxprocs)
 	atomic.Store(&sched.gcwaiting, 1)
 	preemptall()
 	// stop current P
@@ -1057,7 +1057,7 @@ func stopTheWorldWithSema() {
 
 	// sanity checks
 	bad := ""
-	if sched.stopwait != 0 {
+	if atomic.Load(&sched.stopwait) != 0 {
 		bad = "stopTheWorld: not stopped (stopwait != 0)"
 	} else {
 		for _, p := range allp {
@@ -1342,7 +1342,7 @@ func forEachP(fn func(*p)) {
 	if sched.safePointWait != 0 {
 		throw("forEachP: sched.safePointWait != 0")
 	}
-	sched.safePointWait = gomaxprocs - 1
+	sched.safePointWait = uint32(gomaxprocs - 1)
 	sched.safePointFn = fn
 
 	// Ask all Ps to run the safe point function.
@@ -1400,7 +1400,7 @@ func forEachP(fn func(*p)) {
 			preemptall()
 		}
 	}
-	if sched.safePointWait != 0 {
+	if atomic.Load(&sched.safePointWait) != 0 {
 		throw("forEachP: not done")
 	}
 	for _, p := range allp {
diff --git a/src/runtime/runtime2.go b/src/runtime/runtime2.go
index df9cbaef20..1cd5aa9a79 100644
--- a/src/runtime/runtime2.go
+++ b/src/runtime/runtime2.go
@@ -613,7 +613,7 @@ type schedt struct {
 	freem *m
 
 	gcwaiting  uint32 // gc is waiting to run
-	stopwait   int32
+	stopwait   uint32
 	stopnote   note
 	sysmonwait uint32
 	sysmonnote note
@@ -621,7 +621,7 @@ type schedt struct {
 	// safepointFn should be called on each P at the next GC
 	// safepoint if p.runSafePointFn is set.
 	safePointFn   func(*p)
-	safePointWait int32
+	safePointWait uint32
 	safePointNote note
 
 	profilehz int32 // cpu profiling rate