Index: src/runtime/proc.go
--- src/runtime/proc.go.orig
+++ src/runtime/proc.go
@@ -1624,10 +1624,8 @@ func startTheWorldWithSema(now int64, w worldStop) int
 // via libcall.
 func usesLibcall() bool {
 	switch GOOS {
-	case "aix", "darwin", "illumos", "ios", "solaris", "windows":
+	case "aix", "darwin", "illumos", "ios", "openbsd", "solaris", "windows":
 		return true
-	case "openbsd":
-		return GOARCH != "mips64"
 	}
 	return false
 }
@@ -1636,10 +1634,8 @@ func usesLibcall() bool {
 // system-allocated stack.
 func mStackIsSystemAllocated() bool {
 	switch GOOS {
-	case "aix", "darwin", "plan9", "illumos", "ios", "solaris", "windows":
+	case "aix", "darwin", "illumos", "ios", "openbsd", "plan9", "solaris", "windows":
 		return true
-	case "openbsd":
-		return GOARCH != "mips64"
 	}
 	return false
 }