Merge remote-tracking branch 'upstream/master' into epollset
diff --git a/src/core/iomgr/pollset_multipoller_with_epoll.c b/src/core/iomgr/pollset_multipoller_with_epoll.c
index 911d820..d117485 100644
--- a/src/core/iomgr/pollset_multipoller_with_epoll.c
+++ b/src/core/iomgr/pollset_multipoller_with_epoll.c
@@ -90,8 +90,10 @@
 
 void grpc_remove_fd_from_all_epoll_sets(int fd) {
   int err;
+  gpr_once_init(&init_epoll_fd_list_mu, init_mu);
   gpr_mu_lock(&epoll_fd_list_mu);
   if (epoll_fd_global_list.count == 0) {
+    gpr_mu_unlock(&epoll_fd_list_mu);
     return;
   }
   for (size_t i = 0; i < epoll_fd_global_list.count; i++) {