diff --git a/Doc/library/subprocess.rst b/Doc/library/subprocess.rst
index 4c4f4ae..946a504 100644
--- a/Doc/library/subprocess.rst
+++ b/Doc/library/subprocess.rst
@@ -157,6 +157,12 @@
 
       retcode = call(["ls", "-l"])
 
+   .. warning::
+
+      Like :meth:`Popen.wait`, this will deadlock if the child process
+      generates enough output to a stdout or stderr pipe such that it blocks
+      waiting for the OS pipe buffer to accept more data.
+
 
 .. function:: check_call(*popenargs, **kwargs)
 
@@ -171,6 +177,10 @@
 
    .. versionadded:: 2.5
 
+   .. warning::
+
+      See the warning for :func:`call`.
+
 
 .. function:: check_output(*popenargs, **kwargs)