diff --git a/src/channel.c b/src/channel.c
index e4dbcf6..3792b35 100644
--- a/src/channel.c
+++ b/src/channel.c
@@ -3589,10 +3589,17 @@
     sock_T	fd;
     int		timeout;
     chanpart_T	*chanpart = &channel->ch_part[part];
+    int		retval = FAIL;
 
     ch_log(channel, "Blocking read JSON for id %d", id);
+
+    // Not considered a safe state here, since we are processing a JSON message
+    // and parsing other messages while waiting.
+    enter_unsafe_state();
+
     if (id >= 0)
 	channel_add_block_id(chanpart, id);
+
     for (;;)
     {
 	more = channel_parse_json(channel, part);
@@ -3600,10 +3607,9 @@
 	// search for message "id"
 	if (channel_get_json(channel, part, id, TRUE, rettv) == OK)
 	{
-	    if (id >= 0)
-		channel_remove_block_id(chanpart, id);
 	    ch_log(channel, "Received JSON for id %d", id);
-	    return OK;
+	    retval = OK;
+	    break;
 	}
 
 	if (!more)
@@ -3659,7 +3665,11 @@
     }
     if (id >= 0)
 	channel_remove_block_id(chanpart, id);
-    return FAIL;
+
+    // This may trigger a SafeState autocommand.
+    leave_unsafe_state();
+
+    return retval;
 }
 
 /*
@@ -4195,9 +4205,9 @@
     free_job_options(&opt);
 }
 
-# define KEEP_OPEN_TIME 20  /* msec */
+#define KEEP_OPEN_TIME 20  /* msec */
 
-# if (defined(UNIX) && !defined(HAVE_SELECT)) || defined(PROTO)
+#if (defined(UNIX) && !defined(HAVE_SELECT)) || defined(PROTO)
 /*
  * Add open channels to the poll struct.
  * Return the adjusted struct index.
@@ -4288,9 +4298,9 @@
 
     return ret;
 }
-# endif /* UNIX && !HAVE_SELECT */
+#endif /* UNIX && !HAVE_SELECT */
 
-# if (!defined(MSWIN) && defined(HAVE_SELECT)) || defined(PROTO)
+#if (!defined(MSWIN) && defined(HAVE_SELECT)) || defined(PROTO)
 
 /*
  * The "fd_set" type is hidden to avoid problems with the function proto.
@@ -4381,7 +4391,7 @@
 	if (ret > 0 && in_part->ch_fd != INVALID_FD
 					    && FD_ISSET(in_part->ch_fd, wfds))
 	{
-	    /* Clear the flag first, ch_fd may change in channel_write_input(). */
+	    // Clear the flag first, ch_fd may change in channel_write_input().
 	    FD_CLR(in_part->ch_fd, wfds);
 	    channel_write_input(channel);
 	    --ret;
@@ -4390,11 +4400,12 @@
 
     return ret;
 }
-# endif /* !MSWIN && HAVE_SELECT */
+#endif // !MSWIN && HAVE_SELECT
 
 /*
  * Execute queued up commands.
- * Invoked from the main loop when it's safe to execute received commands.
+ * Invoked from the main loop when it's safe to execute received commands,
+ * and during a blocking wait for ch_evalexpr().
  * Return TRUE when something was done.
  */
     int