From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755484Ab2CXQol (ORCPT ); Sat, 24 Mar 2012 12:44:41 -0400 Received: from mail-bk0-f46.google.com ([209.85.214.46]:52500 "EHLO mail-bk0-f46.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1754869Ab2CXQoj (ORCPT ); Sat, 24 Mar 2012 12:44:39 -0400 Date: Sat, 24 Mar 2012 20:43:35 +0400 From: Anton Vorontsov To: Peter Zijlstra Cc: Andrew Morton , Oleg Nesterov , Russell King , Mike Frysinger , Benjamin Herrenschmidt , Richard Weinberger , Paul Mundt , KOSAKI Motohiro , John Stultz , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, uclinux-dist-devel@blackfin.uclinux.org, linuxppc-dev@lists.ozlabs.org, linux-sh@vger.kernel.org, user-mode-linux-devel@lists.sourceforge.net, linux-mm@kvack.org Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes Message-ID: <20120324164335.GA4955@lizard> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> <1332593303.16159.28.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <1332593303.16159.28.camel@twins> User-Agent: Mutt/1.5.21 (2010-09-15) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sat, Mar 24, 2012 at 01:48:23PM +0100, Peter Zijlstra wrote: > On Sat, 2012-03-24 at 14:30 +0400, Anton Vorontsov wrote: > > Traversing the tasks requires holding tasklist_lock, otherwise it > > is unsafe. > > No it doesn't, it either requires tasklist_lock or rcu_read_lock(). Well, currently the code does neither. :-) -- Anton Vorontsov Email: cbouatmailru@gmail.com