From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753977AbbCBMeN (ORCPT ); Mon, 2 Mar 2015 07:34:13 -0500 Received: from cpsmtpb-ews05.kpnxchange.com ([213.75.39.8]:59863 "EHLO cpsmtpb-ews05.kpnxchange.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753885AbbCBMeJ (ORCPT ); Mon, 2 Mar 2015 07:34:09 -0500 Message-ID: <1425299648.24292.118.camel@x220> Subject: Re: [PATCH 01/16] CONFIG_DISABLE_OBSOLETE_CPUMASK_FUNCTIONS: set if CPUMASK_OFFSTACK. From: Paul Bolle To: Rusty Russell Cc: linux-kernel@vger.kernel.org Date: Mon, 02 Mar 2015 13:34:08 +0100 In-Reply-To: <1425296150-4722-1-git-send-email-rusty@rustcorp.com.au> References: <1425296150-4722-1-git-send-email-rusty@rustcorp.com.au> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.10.4 (3.10.4-4.fc20) Mime-Version: 1.0 Content-Transfer-Encoding: 7bit X-OriginalArrivalTime: 02 Mar 2015 12:34:08.0126 (UTC) FILETIME=[2D7E99E0:01D054E5] X-RcptDomain: vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Mon, 2015-03-02 at 22:05 +1030, Rusty Russell wrote: > Using these functions with offstack cpus is unsafe. They use all NR_CPUS > bits, unstead of nr_cpumask_bits. > > In particular, lustre (in staging) used cpus_ and that caused a bug. > > Reported-by: Oleg Drokin > Signed-off-by: Rusty Russell > --- > lib/Kconfig | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/lib/Kconfig b/lib/Kconfig > index 87da53bb1fef..722427805220 100644 > --- a/lib/Kconfig > +++ b/lib/Kconfig > @@ -398,8 +398,8 @@ config CPUMASK_OFFSTACK > stack overflow. > > config DISABLE_OBSOLETE_CPUMASK_FUNCTIONS > - bool "Disable obsolete cpumask functions" if DEBUG_PER_CPU_MAPS > - depends on BROKEN > + bool > + depends on CPUMASK_OFFSTACK This removes the "prompt" from this symbol's entry. And nothing selects it either (not in next-20150302 nor in this series). So I think this just disables this Kconfig symbol entirely. Ie, it can't be set even if CPUMAK_OFFSTACK is set. Should this entry perhaps be using def_bool y instead? > config CPU_RMAP > bool Thanks, Paul Bolle