Index: glibc-2.12-2-gc4ccff1/nptl/allocatestack.c

===================================================================

--- glibc-2.12-2-gc4ccff1.orig/nptl/allocatestack.c

+++ glibc-2.12-2-gc4ccff1/nptl/allocatestack.c

@@ -994,7 +994,16 @@ setxid_mark_thread (struct xid_command *

       /* If the thread is exiting right now, ignore it.  */

       if ((ch & EXITING_BITMASK) != 0)

-	return;

+	{

+	  /* Release the futex if there is no other setxid in

+	     progress.  */

+	  if ((ch & SETXID_BITMASK) == 0)

+	    {

+	      t->setxid_futex = 1;

+	      lll_futex_wake (&t->setxid_futex, 1, LLL_PRIVATE);

+	    }

+	  return;

+	}

     }

   while (atomic_compare_and_exchange_bool_acq (&t->cancelhandling,

 					       ch | SETXID_BITMASK, ch));