commit 230b85f414291ac955827aba15cfbd103ab6ebdd
Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date:   Thu Jun 9 01:15:10 2016 +0200

    Fix pipe() call returning EINTR sometimes
    
    because it uses a critical section

diff --git a/hurd/hurdsock.c b/hurd/hurdsock.c
index 0f52f37..261f654 100644
--- a/hurd/hurdsock.c
+++ b/hurd/hurdsock.c
@@ -52,6 +52,7 @@ _hurd_socket_server (int domain, int dead)
       return MACH_PORT_NULL;
     }
 
+retry:
   HURD_CRITICAL_BEGIN;
   __mutex_lock (&lock);
 
@@ -102,6 +103,10 @@ _hurd_socket_server (int domain, int dead)
   __mutex_unlock (&lock);
   HURD_CRITICAL_END;
 
+  if (!server && errno == EINTR)
+    /* Got a signal while inside an RPC of the critical section, retry again */
+    goto retry;
+
   return server;
 }