From mboxrd@z Thu Jan 1 00:00:00 1970 From: Anton Vorontsov Date: Sat, 24 Mar 2012 16:43:35 +0000 Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes Message-Id: <20120324164335.GA4955@lizard> List-Id: References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> <1332593303.16159.28.camel@twins> In-Reply-To: <1332593303.16159.28.camel@twins> MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: linux-arm-kernel@lists.infradead.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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Date: Sat, 24 Mar 2012 20:43:35 +0400 From: Anton Vorontsov 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> Sender: linux-kernel-owner@vger.kernel.org Subject: Re: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes 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 List-ID: 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 From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-bk0-f51.google.com (mail-bk0-f51.google.com [209.85.214.51]) (using TLSv1 with cipher ECDHE-RSA-RC4-SHA (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority" (not verified)) by ozlabs.org (Postfix) with ESMTPS id D1302B6FBE for ; Sun, 25 Mar 2012 03:44:39 +1100 (EST) Received: by mail-bk0-f51.google.com with SMTP id j10so3335324bkw.38 for ; Sat, 24 Mar 2012 09:44:39 -0700 (PDT) Date: Sat, 24 Mar 2012 20:43:35 +0400 From: Anton Vorontsov To: Peter Zijlstra 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 In-Reply-To: <1332593303.16159.28.camel@twins> 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, 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 From mboxrd@z Thu Jan 1 00:00:00 1970 From: anton.vorontsov@linaro.org (Anton Vorontsov) Date: Sat, 24 Mar 2012 20:43:35 +0400 Subject: [PATCH 07/10] um: Should hold tasklist_lock while traversing processes In-Reply-To: <1332593303.16159.28.camel@twins> References: <20120324102609.GA28356@lizard> <20120324103030.GG29067@lizard> <1332593303.16159.28.camel@twins> Message-ID: <20120324164335.GA4955@lizard> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.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 at gmail.com From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx125.postini.com [74.125.245.125]) by kanga.kvack.org (Postfix) with SMTP id E11856B004D for ; Sat, 24 Mar 2012 12:44:39 -0400 (EDT) Received: by mail-bk0-f41.google.com with SMTP id q16so4417103bkw.14 for ; Sat, 24 Mar 2012 09:44:39 -0700 (PDT) Date: Sat, 24 Mar 2012 20:43:35 +0400 From: Anton Vorontsov 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> Sender: owner-linux-mm@kvack.org List-ID: 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 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 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org