From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932454AbeCKLD7 (ORCPT ); Sun, 11 Mar 2018 07:03:59 -0400 Received: from isilmar-4.linta.de ([136.243.71.142]:54122 "EHLO isilmar-4.linta.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932136AbeCKK4r (ORCPT ); Sun, 11 Mar 2018 06:56:47 -0400 From: Dominik Brodowski To: linux-kernel@vger.kernel.org, luto@kernel.org, torvalds@linux-foundation.org, mingo@kernel.org, viro@zeniv.linux.org.uk, akpm@linux-foundation.org Cc: Thomas Gleixner , Ingo Molnar , Peter Zijlstra , Darren Hart Subject: [RFC PATCH 03/35] syscalls: mm_release(): use do_futex() instead of sys_futex() Date: Sun, 11 Mar 2018 11:55:25 +0100 Message-Id: <20180311105557.20807-4-linux@dominikbrodowski.net> X-Mailer: git-send-email 2.16.2 In-Reply-To: <20180311105557.20807-1-linux@dominikbrodowski.net> References: <20180311105557.20807-1-linux@dominikbrodowski.net> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org sys_futex() is a wrapper to do_futex() which does not modify any values here: - uaddr, val and val3 are kept the same - op is masked with FUTEX_CMD_MASK, but is always set to FUTEX_WAKE. Therefore, val2 is always 0. - as utime is set to NULL, *timeout is NULL CC: Thomas Gleixner CC: Ingo Molnar CC: Peter Zijlstra CC: Darren Hart CC: Andrew Morton Signed-off-by: Dominik Brodowski --- kernel/fork.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/kernel/fork.c b/kernel/fork.c index e5d9d405ae4e..b1e031aac9db 100644 --- a/kernel/fork.c +++ b/kernel/fork.c @@ -1198,8 +1198,8 @@ void mm_release(struct task_struct *tsk, struct mm_struct *mm) * not set up a proper pointer then tough luck. */ put_user(0, tsk->clear_child_tid); - sys_futex(tsk->clear_child_tid, FUTEX_WAKE, - 1, NULL, NULL, 0); + do_futex(tsk->clear_child_tid, FUTEX_WAKE, + 1, NULL, NULL, 0, 0); } tsk->clear_child_tid = NULL; } -- 2.16.2