From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752584Ab1IOBHE (ORCPT ); Wed, 14 Sep 2011 21:07:04 -0400 Received: from szxga04-in.huawei.com ([119.145.14.67]:51140 "EHLO szxga04-in.huawei.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752243Ab1IOBHB (ORCPT ); Wed, 14 Sep 2011 21:07:01 -0400 Date: Thu, 15 Sep 2011 09:06:50 +0800 From: "canquan.shen" Subject: [PATCH v4] acpi: Fix CPU hot removal problem X-Originating-IP: [10.166.80.130] To: len.brown@intel.com Cc: Bjorn Helgaas , "shemminger@vyatta.com" , "yakui.zhao@intel.com" , "xiaowei.yang@huawei.com" , hanweidong , linqiangmin@huawei.com, "linux-kernel@vger.kernel.org" , "linux-acpi@vger.kernel.org" Message-id: <4E714FAA.8060708@huawei.com> MIME-version: 1.0 Content-type: text/plain; charset=ISO-8859-1; format=flowed Content-transfer-encoding: 7BIT User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:6.0.2) Gecko/20110902 Thunderbird/6.0.2 X-CFilter-Loop: Reflected Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org We run linux as a guest in Xen environment. When we used the xen tools (xm vcpu-set ) to hot add and remove vcpu to and from the guest, we encountered the failure on vcpu removal. We found the reason is that it didn't go to really remove cpu in the cpu removal code path. This patch adds acpi_bus_trim in acpi_process_hotplug_notify to fix this issue. With this patch, it works fine for us. Signed-off-by:Canquan Shen --- drivers/acpi/processor_driver.c | 6 ++++++ 1 files changed, 6 insertions(+), 0 deletions(-) diff --git a/drivers/acpi/processor_driver.c b/drivers/acpi/processor_driver.c index a4e0f1b..03d92d6 100644 --- a/drivers/acpi/processor_driver.c +++ b/drivers/acpi/processor_driver.c @@ -641,6 +641,7 @@ static void acpi_processor_hotplug_notify(acpi_handle handle, struct acpi_processor *pr; struct acpi_device *device = NULL; int result; + u32 id; switch (event) { @@ -677,6 +678,11 @@ static void acpi_processor_hotplug_notify(acpi_handle handle, "Driver data is NULL, dropping EJECT\n"); return; } + id = pr->id; + if (acpi_bus_trim(device, 1)) { + printk(KERN_ERR PREFIX + "Fail to Remove CPU %d\n", id); + } break; default: ACPI_DEBUG_PRINT((ACPI_DB_INFO, -- 1.7.6.0