Do not free io context when taking recursive faults in do_exit

When taking recursive faults in do_exit, if the io_context is not null,
exit_io_context() is being called. But it might decrement the refcount
more than once. It is better to leave this task alone.

Signed-off-by: Nikanth Karthikesan <knikanth@suse.de>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>

kernel/exit.c

@@ -1037,8 +1037,6 @@ NORET_TYPE void do_exit(long code)
 		 * task into the wait for ever nirwana as well.
 		 */
 		tsk->flags |= PF_EXITPIDONE;
-		if (tsk->io_context)
-			exit_io_context();
 		set_current_state(TASK_UNINTERRUPTIBLE);
 		schedule();
 	}