From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from caramon.arm.linux.org.uk (caramon.arm.linux.org.uk [217.147.92.249]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (Client did not present a certificate) by ozlabs.org (Postfix) with ESMTP id EC761DDE03 for ; Tue, 13 Mar 2007 20:41:03 +1100 (EST) Date: Tue, 13 Mar 2007 09:40:39 +0000 From: Russell King To: Heiko Carstens Subject: Re: /sys/devices/system/cpu/cpuX/online are missing Message-ID: <20070313094038.GA20518@flint.arm.linux.org.uk> References: <20070311222652.5ea40da1.pochini@shiny.it> <20070312085826.GA9985@osiris.boeblingen.de.ibm.com> <20070313090350.GA9890@osiris.boeblingen.de.ibm.com> <20070313091159.GB9890@osiris.boeblingen.de.ibm.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii In-Reply-To: <20070313091159.GB9890@osiris.boeblingen.de.ibm.com> Sender: Russell King Cc: Suresh Siddha , Giuliano Pochini , linux-kernel@vger.kernel.org, linuxppc-dev@ozlabs.org List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On Tue, Mar 13, 2007 at 10:11:59AM +0100, Heiko Carstens wrote: > On Tue, Mar 13, 2007 at 10:03:50AM +0100, Heiko Carstens wrote: > > On Tue, Mar 13, 2007 at 01:39:25AM +0100, Andreas Schwab wrote: > > > Giuliano Pochini writes: > > > > > > > I had a look at arch/powerpc/kernel/smp.c but I'm not familiar at all with > > > > those parts of the kernel. > > > > > > See arch/powerpc/kernel/sysfs.c:topology_init. I don't think there is > > > anything to do here. You probably don't have CONFIG_HOTPLUG_CPU enabled. > > > > I was referring to arch/ppc not arch/powerpc. But it seems that arch/ppc > > doesn't support cpu hotplug anyway. So I guess it's indeed just a missing > > config option. > > > > Grepping a bit further shows that arm suffered by the change that inverted > > the logic if the 'online' attribute for cpus should appear. Since arm > > supports cpu hotplug but the patch left arm out, it doesn't work there > > anymore (cc'ing arm people: changeset 72486f1f8f0a2bc828b9d30cf4690cf2dd6807fc > > is most probably disabling cpu hotplug support on arm like it did on s390). > > Should have cc'ed Suresh Siddha who caused the breakage ;) Welcome to why cleanups are bad news. ;( Yes, ARM also needs to be fixed and I'd ask that in future people doing cleanups in core code take a little more time to review the code before submitting patches *AND* give heads-up to *EVERYONE* who might be affected by the change. -- Russell King Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/ maintainer of: