Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755861Ab3HFKHK (ORCPT ); Tue, 6 Aug 2013 06:07:10 -0400 Received: from fgwmail5.fujitsu.co.jp ([192.51.44.35]:39255 "EHLO fgwmail5.fujitsu.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755808Ab3HFKHG (ORCPT ); Tue, 6 Aug 2013 06:07:06 -0400 X-SecurityPolicyCheck: OK by SHieldMailChecker v2.0.1 X-SHieldMailCheckerPolicyVersion: FJ-ISEC-20120718-3 Message-ID: <5200CAAD.5080102@jp.fujitsu.com> Date: Tue, 6 Aug 2013 19:06:37 +0900 From: Yasuaki Ishimatsu User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:17.0) Gecko/20130620 Thunderbird/17.0.7 MIME-Version: 1.0 To: , , CC: , Subject: Re: acpi_bus_trim does not detach devices in post order References: <52006888.5030203@jp.fujitsu.com> In-Reply-To: <52006888.5030203@jp.fujitsu.com> Content-Type: text/plain; charset="ISO-2022-JP" Content-Transfer-Encoding: 7bit X-SecurityPolicyCheck-GC: OK by FENCE-Mail Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2689 Lines: 73 (2013/08/06 12:07), Yasuaki Ishimatsu wrote: > > I acked the following commit but I hit a problem by the commit. > So I report it. > > commit cecdb193c8d91a42d9489d00618cc3dfff92e55a > Author: Rafael J. Wysocki > Date: Tue Jan 15 13:24:02 2013 +0100 > > ACPI / scan: Change the implementation of acpi_bus_trim() > > Before applying the commit, acpi_bus_trim() detachs devices in post order. > > When I hot add memory devices and processor devices by container device > in my x86 box, memory devices are added first and processor devices are added > second. So I expect that processor devices are removed first and memory > devices are removed second when I remove them. And before applying the > commit, acpi_bus_trim() did so. > > But after appling the commit, acpi_bus_trim() does not detach devices in > post order. So when I remove them, memory devices are removed first and > processor devices are removed second. > > By this, I hit a problem. > > In Linux on x86 arch, NUMA node is depend on memory devices. So new NUMA > node is created at memory hot adding. Thus when I hot add memory devices and > processor devices, we must hot add memory device first. Otherwise, processor > devices are not set to correct NUMA node number. > > And Linux expects that when removing them, processor devices are removed > first before removing memory devices. But acpi_bus_trim() does not do so. > By this, NUMA node is not cleared in my x86 box when hot removing memory device > and processor devices. When removing memory devices, NUMA node is cleared. > But if there are processor devices related with the NUMA node, NUMA node is > not be cleared at memory hot removing. > > So when I remove them, NUMA node's sysfs file remained as follows: I had little mistake. CPU also tries to clear NUMA node. But current implementation has bug. So I'll fix it. Thanks, Yasuaki Ishimatsu > > # ls /sys/devices/system/node/node1/ > compact cpumap meminfo power subsystem vmstat > cpulist distance numastat scan_unevictable_pages uevent > > CPU and memory sysfs files are removed correctly. But node1 sysfs file > remained. > > Thanks, > Yasuaki Ishimatsu > > > > > > > -- > To unsubscribe from this list: send the line "unsubscribe linux-acpi" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- 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/