From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751665AbaIJNcb (ORCPT ); Wed, 10 Sep 2014 09:32:31 -0400 Received: from mx1.redhat.com ([209.132.183.28]:65315 "EHLO mx1.redhat.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751634AbaIJNca (ORCPT ); Wed, 10 Sep 2014 09:32:30 -0400 Date: Wed, 10 Sep 2014 14:29:33 +0100 From: Aaron Tomlin To: Chuck Ebbert Cc: peterz@infradead.org, mingo@redhat.com, dzickus@redhat.com, bmr@redhat.com, jcastillo@redhat.com, oleg@redhat.com, pzijlstr@redhat.com, riel@redhat.com, prarit@redhat.com, jgh@redhat.com, linux-kernel@vger.kernel.org, tglx@linutronix.de, x86@kernel.org, rostedt@goodmis.org, hannes@cmpxchg.org, aneesh.kumar@linux.vnet.ibm.com, akpm@linux-foundation.org, akpm@google.com, linuxppc-dev@lists.ozlabs.org, minchan@kernel.org Subject: Re: [PATCH v2 1/3] init/main.c: Give init_task a canary Message-ID: <20140910132933.GG1436@atomlin.usersys.redhat.com> References: <20140904161124.GD1436@atomlin.usersys.redhat.com> <1410255749-2956-1-git-send-email-atomlin@redhat.com> <1410255749-2956-2-git-send-email-atomlin@redhat.com> <20140910022654.29abc9f3@as> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20140910022654.29abc9f3@as> X-PGP-Key: http://pgp.mit.edu/pks/lookup?search=atomlin%40redhat.com X-PGP-Fingerprint: 7906 84EB FA8A 9638 8D1E 6E9B E2DE 9658 19CC 77D6 User-Agent: Mutt/1.5.22.1 (2013-10-16) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Sep 10, 2014 at 02:26:54AM -0500, Chuck Ebbert wrote: > On Tue, 9 Sep 2014 10:42:27 +0100 > Aaron Tomlin wrote: > > > +void task_stack_end_magic(struct task_struct *tsk) > > +{ > > + unsigned long *stackend; > > + > > + stackend = end_of_stack(tsk); > > + *stackend = STACK_END_MAGIC; /* for overflow detection */ > > +} > > + > > For clarity this should probably be called set_task_stack_end_magic(). Agreed. > And has this been tested on parisc and metag, which use STACK_GROWSUP ? > I can't see how end_of_stack() as it's defined now could work on those archs. AFAIU, dup_task_struct() has always done this explicitly. I see no reason why init_task requires special attention. -- Aaron Tomlin From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mx1.redhat.com (mx1.redhat.com [209.132.183.28]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 46FFA1A018A for ; Wed, 10 Sep 2014 23:32:28 +1000 (EST) Date: Wed, 10 Sep 2014 14:29:33 +0100 From: Aaron Tomlin To: Chuck Ebbert Subject: Re: [PATCH v2 1/3] init/main.c: Give init_task a canary Message-ID: <20140910132933.GG1436@atomlin.usersys.redhat.com> References: <20140904161124.GD1436@atomlin.usersys.redhat.com> <1410255749-2956-1-git-send-email-atomlin@redhat.com> <1410255749-2956-2-git-send-email-atomlin@redhat.com> <20140910022654.29abc9f3@as> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 In-Reply-To: <20140910022654.29abc9f3@as> Cc: dzickus@redhat.com, jcastillo@redhat.com, riel@redhat.com, x86@kernel.org, akpm@linux-foundation.org, peterz@infradead.org, bmr@redhat.com, prarit@redhat.com, oleg@redhat.com, rostedt@goodmis.org, linux-kernel@vger.kernel.org, minchan@kernel.org, mingo@redhat.com, aneesh.kumar@linux.vnet.ibm.com, akpm@google.com, hannes@cmpxchg.org, jgh@redhat.com, linuxppc-dev@lists.ozlabs.org, tglx@linutronix.de, pzijlstr@redhat.com List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Wed, Sep 10, 2014 at 02:26:54AM -0500, Chuck Ebbert wrote: > On Tue, 9 Sep 2014 10:42:27 +0100 > Aaron Tomlin wrote: > > > +void task_stack_end_magic(struct task_struct *tsk) > > +{ > > + unsigned long *stackend; > > + > > + stackend = end_of_stack(tsk); > > + *stackend = STACK_END_MAGIC; /* for overflow detection */ > > +} > > + > > For clarity this should probably be called set_task_stack_end_magic(). Agreed. > And has this been tested on parisc and metag, which use STACK_GROWSUP ? > I can't see how end_of_stack() as it's defined now could work on those archs. AFAIU, dup_task_struct() has always done this explicitly. I see no reason why init_task requires special attention. -- Aaron Tomlin