diff --git a/extmod/modtrezormsg/modtrezormsg-unix.h b/extmod/modtrezormsg/modtrezormsg-unix.h
index 7080e150e7..988f6bc00a 100644
--- a/extmod/modtrezormsg/modtrezormsg-unix.h
+++ b/extmod/modtrezormsg/modtrezormsg-unix.h
@@ -1,5 +1,6 @@
 #include <arpa/inet.h>
 #include <sys/socket.h>
+#include <fcntl.h>
 #include <assert.h>
 
 #define TREZOR_PORT 21324
@@ -10,9 +11,11 @@ static socklen_t slen = 0;
 
 void msg_init(void)
 {
-    s = socket(AF_INET, SOCK_DGRAM | SOCK_NONBLOCK, IPPROTO_UDP);
+    s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
     assert(s != -1);
 
+    fcntl(s, F_SETFL, O_NONBLOCK);
+
     si_me.sin_family = AF_INET;
     si_me.sin_port = htons(TREZOR_PORT);
     si_me.sin_addr.s_addr = htonl(INADDR_ANY);