From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
	id S1754014AbbJPKWg (ORCPT <rfc822;w@1wt.eu>);
	Fri, 16 Oct 2015 06:22:36 -0400
Received: from www.linutronix.de ([62.245.132.108]:36734 "EHLO
	Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org
	with ESMTP id S1753917AbbJPKWe (ORCPT
	<rfc822;linux-kernel@vger.kernel.org>);
	Fri, 16 Oct 2015 06:22:34 -0400
Date: Fri, 16 Oct 2015 12:21:51 +0200 (CEST)
From: Thomas Gleixner <tglx@linutronix.de>
To: Heiko Carstens <heiko.carstens@de.ibm.com>
cc: Stefan Liebler <stli@linux.vnet.ibm.com>,
        Preeti U Murthy <preeti@linux.vnet.ibm.com>,
        Peter Zijlstra <peterz@infradead.org>, linux-kernel@vger.kernel.org
Subject: Re: futex timeout not working? (bisected)
In-Reply-To: <20151015104347.GA4166@osiris>
Message-ID: <alpine.DEB.2.11.1510161218400.3960@nanos>
References: <20151015104347.GA4166@osiris>
User-Agent: Alpine 2.11 (DEB 23 2013-08-11)
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII
X-Linutronix-Spam-Score: -1.0
X-Linutronix-Spam-Level: -
X-Linutronix-Spam-Status: No , -1.0 points, 5.0 required,  ALL_TRUSTED=-1,SHORTCIRCUIT=-0.0001
Sender: linux-kernel-owner@vger.kernel.org
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Heiko,

On Thu, 15 Oct 2015, Heiko Carstens wrote:
>   /* We wait for half a second.  */
>   ts.tv_nsec += 500000000;
>   if (ts.tv_nsec >= 1000000000)
>     {
>       ++ts.tv_sec;
>       ts.tv_nsec -= 1000000000;
>     }
> 
>   ret = syscall (__NR_futex, &futex_word, op, expected, ts, NULL, FUTEX_BITSET_MATCH_ANY);

If you actually hand in a pointer to 'ts' then the program works as
expected even with the commit in question applied.

Thanks,

	tglx