Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1762685AbXEPQgE (ORCPT ); Wed, 16 May 2007 12:36:04 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1762301AbXEPQfx (ORCPT ); Wed, 16 May 2007 12:35:53 -0400 Received: from smtp2.linux-foundation.org ([207.189.120.14]:44384 "EHLO smtp2.linux-foundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1762083AbXEPQfu (ORCPT ); Wed, 16 May 2007 12:35:50 -0400 Date: Wed, 16 May 2007 09:33:44 -0700 From: Andrew Morton To: Aaron Durbin Cc: linux-kernel@vger.kernel.org, len.brown@intel.com Subject: Re: [PATCH] acpi: Fix potential call to a freed memory section. Message-Id: <20070516093344.cf0ea55e.akpm@linux-foundation.org> In-Reply-To: <20070516160911.GA15066@google.com> References: <20070516160911.GA15066@google.com> X-Mailer: Sylpheed 2.4.1 (GTK+ 2.8.17; x86_64-unknown-linux-gnu) Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2550 Lines: 75 On Wed, 16 May 2007 09:09:11 -0700 Aaron Durbin wrote: > Strip __cpuinit[data] from Node <-> PXM routines and supporting data structures. > Also make pxm_to_node_map and node_to_pxm_map local to the numa acpi module. > > This fixes a bug triggered by the following conditions: > - boot on a machine with a SLIT table defined > - kernel is configured w/ CONFIG_HOTPLUG_CPU=n > - cat /sys/devices/system/node/node*/distance > This will cause an oops by calling into a freed memory section. > > In particular, on x86_64, __node_distance calls node_to_pxm(). > Yeah, those section warnings we get aren't just noise. I think this patch is also needed in 2.6.21.x, yes? > --- > > diff --git a/drivers/acpi/numa.c b/drivers/acpi/numa.c > index 8fcd6a1..a2efae8 100644 > --- a/drivers/acpi/numa.c > +++ b/drivers/acpi/numa.c > @@ -40,19 +40,19 @@ #define PXM_INVAL -1 > #define NID_INVAL -1 > > /* maps to convert between proximity domain and logical node ID */ > -int __cpuinitdata pxm_to_node_map[MAX_PXM_DOMAINS] > +static int pxm_to_node_map[MAX_PXM_DOMAINS] > = { [0 ... MAX_PXM_DOMAINS - 1] = NID_INVAL }; > -int __cpuinitdata node_to_pxm_map[MAX_NUMNODES] > +static int node_to_pxm_map[MAX_NUMNODES] > = { [0 ... MAX_NUMNODES - 1] = PXM_INVAL }; > > -int __cpuinit pxm_to_node(int pxm) > +int pxm_to_node(int pxm) > { > if (pxm < 0) > return NID_INVAL; > return pxm_to_node_map[pxm]; > } > > -int __cpuinit node_to_pxm(int node) > +int node_to_pxm(int node) > { > if (node < 0) > return PXM_INVAL; > diff --git a/include/acpi/acpi_numa.h b/include/acpi/acpi_numa.h > index f9d2bde..b62cd36 100644 > --- a/include/acpi/acpi_numa.h > +++ b/include/acpi/acpi_numa.h > @@ -11,11 +11,8 @@ #else > #define MAX_PXM_DOMAINS (256) /* Old pxm spec is defined 8 bit */ > #endif > > -extern int __cpuinitdata pxm_to_node_map[MAX_PXM_DOMAINS]; > -extern int __cpuinitdata node_to_pxm_map[MAX_NUMNODES]; > - > -extern int __cpuinit pxm_to_node(int); > -extern int __cpuinit node_to_pxm(int); > +extern int pxm_to_node(int); > +extern int node_to_pxm(int); > extern int __cpuinit acpi_map_pxm_to_node(int); > extern void __cpuinit acpi_unmap_pxm_to_node(int); > Moving from __fooinit into .text is always safe. Len, do you want me to merge this up? - 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/