Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1763226AbZC0CMd (ORCPT ); Thu, 26 Mar 2009 22:12:33 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1758268AbZC0CMY (ORCPT ); Thu, 26 Mar 2009 22:12:24 -0400 Received: from rv-out-0506.google.com ([209.85.198.236]:64148 "EHLO rv-out-0506.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757206AbZC0CMX (ORCPT ); Thu, 26 Mar 2009 22:12:23 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:date:message-id:subject:from:to:cc:content-type :content-transfer-encoding; b=HbxJFJBZZSj8o78EKGIhVTEoyz+yx3F0w5dy2ZtFd9tITy6d6DTYtxoWRXVVpvUrGd BBcZmpXGek8qPvYJa7dvnpscd6dDHKdnZHy33vUaDXSH8ulXAu9ZagDfEbYlquScF26t 4Z4+PosiqblTHLiKmJRnKwSVL7E6y6ljDgD2Y= MIME-Version: 1.0 Date: Fri, 27 Mar 2009 11:12:21 +0900 Message-ID: <28c262360903261912n4ce235c6wf2f75b2be7faf0f4@mail.gmail.com> Subject: Question about PRIVATE_FUTEX From: Minchan Kim To: Peter Zijlstra , Eric Dumazet Cc: lkml Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 611 Lines: 20 Hi, Peter and Eric. I am not expert about futex. I am sorry if this is dumb question. If we use private futex, get_futex_key don't call get_user_pages_fast which pins page at page table. Then, get_futex_value_locked calls __cpy_from_user_inatomic with pagefault_disable. Who make sure the user page is mapped at app's page table ? -- Kinds regards, Minchan Kim -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/