Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S933580AbbDPKtv (ORCPT ); Thu, 16 Apr 2015 06:49:51 -0400 Received: from www.linutronix.de ([62.245.132.108]:43465 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756684AbbDPKto (ORCPT ); Thu, 16 Apr 2015 06:49:44 -0400 Date: Thu, 16 Apr 2015 12:49:59 +0200 (CEST) From: Thomas Gleixner To: Peter Zijlstra cc: Davidlohr Bueso , Sebastian Andrzej Siewior , linux-kernel@vger.kernel.org, Ingo Molnar , Darren Hart , Steven Rostedt , fredrik.markstrom@windriver.com, Manfred Spraul , Arnaldo Carvalho de Melo Subject: Re: [PATCH 2/3 v2] futex: avoid double wake up in futex_wake() on -RT In-Reply-To: <20150416101637.GC5029@twins.programming.kicks-ass.net> Message-ID: References: <1428419030-20030-1-git-send-email-bigeasy@linutronix.de> <1428419030-20030-3-git-send-email-bigeasy@linutronix.de> <20150410161135.GF3057@linutronix.de> <1428894155.16668.6.camel@stgolabs.net> <1429160982.6795.35.camel@stgolabs.net> <20150416101637.GC5029@twins.programming.kicks-ass.net> 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,URIBL_BLOCKED=0.001 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1051 Lines: 31 On Thu, 16 Apr 2015, Peter Zijlstra wrote: > On Thu, Apr 16, 2015 at 11:19:41AM +0200, Thomas Gleixner wrote: > > So any code which does not handle a spurious wakeup is broken > > independent of the futex changes. So really nothing to worry about. > > Back when we did this: > > http://lkml.iu.edu/hypermail/linux/kernel/1109.1/01941.html > http://lkml.iu.edu/hypermail/linux/kernel/1109.1/01943.html > > Things came apart -- notably sysvsems. > > And yes its true that anything not dealing with spuriuos wakups is > borken, but there's still quite a lot of borken out there, although I > think we fixed all the really common ones. > > But if we decide we want to go do this, I'd propose we reintroduce this > delayed wake list thing again. Indeed. Forgot about that completely. Thanks, tglx -- 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/