From mboxrd@z Thu Jan 1 00:00:00 1970 From: Peter Zijlstra Date: Sat, 24 Mar 2012 12:48:23 +0000 Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes Message-Id: <1332593303.16159.28.camel@twins> List-Id: References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> In-Reply-To: <20120324103030.GG29067@lizard> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.org 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(). From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Message-ID: <1332593303.16159.28.camel@twins> From: Peter Zijlstra Date: Sat, 24 Mar 2012 13:48:23 +0100 In-Reply-To: <20120324103030.GG29067@lizard> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7BIT Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes To: Anton Vorontsov 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 List-ID: 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(). From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from merlin.infradead.org (merlin.infradead.org [IPv6:2001:4978:20e::2]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTPS id C90ABB6FA7 for ; Sat, 24 Mar 2012 23:48:45 +1100 (EST) Message-ID: <1332593303.16159.28.camel@twins> Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes From: Peter Zijlstra To: Anton Vorontsov Date: Sat, 24 Mar 2012 13:48:23 +0100 In-Reply-To: <20120324103030.GG29067@lizard> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> Content-Type: text/plain; charset="ISO-8859-1" Mime-Version: 1.0 Cc: Mike Frysinger , user-mode-linux-devel@lists.sourceforge.net, linux-sh@vger.kernel.org, Richard Weinberger , linuxppc-dev@lists.ozlabs.org, Oleg Nesterov , linux-kernel@vger.kernel.org, linux-mm@kvack.org, Paul Mundt , John Stultz , KOSAKI Motohiro , Russell King , Andrew Morton , uclinux-dist-devel@blackfin.uclinux.org, linux-arm-kernel@lists.infradead.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Sat, 2012-03-24 at 14:30 +0400, Anton Vorontsov wrote: > Traversing the tasks requires holding tasklist_lock, otherwise it > is unsafe.=20 No it doesn't, it either requires tasklist_lock or rcu_read_lock(). From mboxrd@z Thu Jan 1 00:00:00 1970 From: a.p.zijlstra@chello.nl (Peter Zijlstra) Date: Sat, 24 Mar 2012 13:48:23 +0100 Subject: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes In-Reply-To: <20120324103030.GG29067@lizard> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> Message-ID: <1332593303.16159.28.camel@twins> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org 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(). From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx142.postini.com [74.125.245.142]) by kanga.kvack.org (Postfix) with SMTP id 3A2716B0100 for ; Sat, 24 Mar 2012 08:48:39 -0400 (EDT) Message-ID: <1332593303.16159.28.camel@twins> Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes From: Peter Zijlstra Date: Sat, 24 Mar 2012 13:48:23 +0100 In-Reply-To: <20120324103030.GG29067@lizard> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> Content-Type: text/plain; charset="ISO-8859-1" Content-Transfer-Encoding: quoted-printable Mime-Version: 1.0 Sender: owner-linux-mm@kvack.org List-ID: To: Anton Vorontsov 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 On Sat, 2012-03-24 at 14:30 +0400, Anton Vorontsov wrote: > Traversing the tasks requires holding tasklist_lock, otherwise it > is unsafe.=20 No it doesn't, it either requires tasklist_lock or rcu_read_lock(). -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. 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