From patchwork Mon Jan 29 12:56:31 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "gregkh@linuxfoundation.org" X-Patchwork-Id: 867303 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Authentication-Results: ozlabs.org; spf=none (mailfrom) smtp.mailfrom=vger.kernel.org (client-ip=209.132.180.67; helo=vger.kernel.org; envelope-from=linux-pci-owner@vger.kernel.org; receiver=) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by ozlabs.org (Postfix) with ESMTP id 3zVhnr1s9Bz9rxj for ; Tue, 30 Jan 2018 08:04:00 +1100 (AEDT) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752984AbeA2UIC (ORCPT ); Mon, 29 Jan 2018 15:08:02 -0500 Received: from mail.linuxfoundation.org ([140.211.169.12]:51718 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752964AbeA2UIA (ORCPT ); Mon, 29 Jan 2018 15:08:00 -0500 Received: from localhost (LFbn-1-12258-90.w90-92.abo.wanadoo.fr [90.92.71.90]) by mail.linuxfoundation.org (Postfix) with ESMTPSA id 094382EF6; Mon, 29 Jan 2018 13:01:30 +0000 (UTC) From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Rui Wang , Thomas Gleixner , tony.luck@intel.com, linux-pci@vger.kernel.org, rjw@rjwysocki.net, linux-acpi@vger.kernel.org, bhelgaas@google.com, Ingo Molnar , Joerg Roedel Subject: [PATCH 4.4 26/74] x86/ioapic: Fix incorrect pointers in ioapic_setup_resources() Date: Mon, 29 Jan 2018 13:56:31 +0100 Message-Id: <20180129123848.802267981@linuxfoundation.org> X-Mailer: git-send-email 2.16.1 In-Reply-To: <20180129123847.507563674@linuxfoundation.org> References: <20180129123847.507563674@linuxfoundation.org> User-Agent: quilt/0.65 MIME-Version: 1.0 Sender: linux-pci-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-pci@vger.kernel.org 4.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rui Wang commit 9d98bcec731756b8688b59ec998707924d716d7b upstream. On a 4-socket Brickland system, hot-removing one ioapic is fine. Hot-removing the 2nd one causes panic in mp_unregister_ioapic() while calling release_resource(). It is because the iomem_res pointer has already been released when removing the first ioapic. To explain the use of &res[num] here: res is assigned to ioapic_resources, and later in ioapic_insert_resources() we do: struct resource *r = ioapic_resources; for_each_ioapic(i) { insert_resource(&iomem_resource, r); r++; } Here 'r' is treated as an arry of 'struct resource', and the r++ ensures that each element of the array is inserted separately. Thus we should call release_resouce() on each element at &res[num]. Fix it by assigning the correct pointers to ioapics[i].iomem_res in ioapic_setup_resources(). Signed-off-by: Rui Wang Signed-off-by: Thomas Gleixner Cc: tony.luck@intel.com Cc: linux-pci@vger.kernel.org Cc: rjw@rjwysocki.net Cc: linux-acpi@vger.kernel.org Cc: bhelgaas@google.com Link: http://lkml.kernel.org/r/1465369193-4816-3-git-send-email-rui.y.wang@intel.com Signed-off-by: Ingo Molnar Acked-by: Joerg Roedel Signed-off-by: Greg Kroah-Hartman --- arch/x86/kernel/apic/io_apic.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) --- a/arch/x86/kernel/apic/io_apic.c +++ b/arch/x86/kernel/apic/io_apic.c @@ -2592,8 +2592,8 @@ static struct resource * __init ioapic_s res[num].flags = IORESOURCE_MEM | IORESOURCE_BUSY; snprintf(mem, IOAPIC_RESOURCE_NAME_SIZE, "IOAPIC %u", i); mem += IOAPIC_RESOURCE_NAME_SIZE; + ioapics[i].iomem_res = &res[num]; num++; - ioapics[i].iomem_res = res; } ioapic_resources = res;