diff -r 60ac28b612af Modules/fcntlmodule.c
--- a/Modules/fcntlmodule.c	Sat Apr 09 11:32:58 2016 +0200
+++ b/Modules/fcntlmodule.c	Sat Apr 09 11:51:38 2016 +0200
@@ -285,9 +285,18 @@ fcntl_flock_impl(PyModuleDef *module, in
     int ret;
 
 #ifdef HAVE_FLOCK
-    Py_BEGIN_ALLOW_THREADS
-    ret = flock(fd, code);
-    Py_END_ALLOW_THREADS
+    while (1) {
+        Py_BEGIN_ALLOW_THREADS
+        ret = flock(fd, code);
+        Py_END_ALLOW_THREADS
+
+        if (!(ret < 0 && errno == EINTR)) {
+            break;
+        }
+        if (PyErr_CheckSignals()) {
+            return NULL;
+        }
+    }
 #else
 
 #ifndef LOCK_SH
@@ -310,9 +319,19 @@ fcntl_flock_impl(PyModuleDef *module, in
             return NULL;
         }
         l.l_whence = l.l_start = l.l_len = 0;
-        Py_BEGIN_ALLOW_THREADS
-        ret = fcntl(fd, (code & LOCK_NB) ? F_SETLK : F_SETLKW, &l);
-        Py_END_ALLOW_THREADS
+
+        while (1) {
+            Py_BEGIN_ALLOW_THREADS
+            ret = fcntl(fd, (code & LOCK_NB) ? F_SETLK : F_SETLKW, &l);
+            Py_END_ALLOW_THREADS
+
+            if (!(ret < 0 && errno == EINTR)) {
+                break;
+            }
+            if (PyErr_CheckSignals()) {
+                return NULL;
+            }
+        }
     }
 #endif /* HAVE_FLOCK */
     if (ret < 0) {
@@ -407,9 +426,19 @@ fcntl_lockf_impl(PyModuleDef *module, in
                 return NULL;
         }
         l.l_whence = whence;
-        Py_BEGIN_ALLOW_THREADS
-        ret = fcntl(fd, (code & LOCK_NB) ? F_SETLK : F_SETLKW, &l);
-        Py_END_ALLOW_THREADS
+
+        while (1) {
+            Py_BEGIN_ALLOW_THREADS
+            ret = fcntl(fd, (code & LOCK_NB) ? F_SETLK : F_SETLKW, &l);
+            Py_END_ALLOW_THREADS
+
+            if (!(ret < 0 && errno == EINTR)) {
+                break;
+            }
+            if (PyErr_CheckSignals()) {
+                return NULL;
+            }
+        }
     }
     if (ret < 0) {
         PyErr_SetFromErrno(PyExc_IOError);