Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754176Ab3HVVoV (ORCPT ); Thu, 22 Aug 2013 17:44:21 -0400 Received: from mx1.redhat.com ([209.132.183.28]:57102 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753431Ab3HVVoU (ORCPT ); Thu, 22 Aug 2013 17:44:20 -0400 Date: Thu, 22 Aug 2013 17:43:47 -0400 From: Richard Guy Briggs To: Peter Zijlstra , linux-audit@redhat.com, linux-kernel@vger.kernel.org Cc: Eric Paris , "Eric W. Biederman" , "Serge E. Hallyn" , Oleg Nesterov , Ingo Molnar , Andrew Morton Subject: Re: [PATCH 11/12] pid: rewrite task helper functions avoiding task->pid and task->tgid Message-ID: <20130822214347.GB21110@madcap2.tricolour.ca> References: <20130822200555.GN31370@twins.programming.kicks-ass.net> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20130822200555.GN31370@twins.programming.kicks-ass.net> 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 Content-Length: 2204 Lines: 66 On Thu, Aug 22, 2013 at 10:05:55PM +0200, Peter Zijlstra wrote: > On Tue, Aug 20, 2013 at 05:32:03PM -0400, Richard Guy Briggs wrote: > > This stops these four task helper functions from using the deprecated and > > error-prone task->pid and task->tgid. > > > > (informed by ebiederman's ea5a4d01) > > Cc: "Eric W. Biederman" > > Signed-off-by: Richard Guy Briggs > > --- > > include/linux/sched.h | 8 ++++---- > > 1 files changed, 4 insertions(+), 4 deletions(-) > > > > diff --git a/include/linux/sched.h b/include/linux/sched.h > > index 8e69807..46e739d 100644 > > --- a/include/linux/sched.h > > +++ b/include/linux/sched.h > > @@ -1579,7 +1579,7 @@ static inline int pid_alive(struct task_struct *p) > > */ > > static inline int is_global_init(struct task_struct *tsk) > > { > > - return tsk->pid == 1; > > + return task_pid_nr(tsk) == 1; > > } > > > > extern struct pid *cad_pid; > > @@ -1930,7 +1930,7 @@ extern struct task_struct *idle_task(int cpu); > > */ > > static inline bool is_idle_task(const struct task_struct *p) > > { > > - return p->pid == 0; > > + return task_pid(p) == &init_struct_pid; > > } > > extern struct task_struct *curr_task(int cpu); > > extern void set_curr_task(int cpu, struct task_struct *p); > > Why would you ever want to do this? It just makes these tests more > expensive for no gain what so ff'ing ever. Backups are generally considered a good idea, but in this case, I'd quote: "A man with one watch knows what time it is. A man with two is never certain." Reminds me of the twist of a phrase frequently seen in the US gov: "Government Duplicity, Do Not Propagate" ;-) Can you suggest a safe way to live with this duplicity? - RGB -- Richard Guy Briggs Senior Software Engineer Kernel Security AMER ENG Base Operating Systems Remote, Ottawa, Canada Voice: +1.647.777.2635 Internal: (81) 32635 Alt: +1.613.693.0684x3545 -- 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/