From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1764645AbYHHWk4 (ORCPT ); Fri, 8 Aug 2008 18:40:56 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752166AbYHHWkt (ORCPT ); Fri, 8 Aug 2008 18:40:49 -0400 Received: from e36.co.us.ibm.com ([32.97.110.154]:41729 "EHLO e36.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751943AbYHHWks (ORCPT ); Fri, 8 Aug 2008 18:40:48 -0400 Subject: Re: [PATCH 2/2] Repost Cell OProfile: SPU mutex lock fix, version 4 From: Carl Love To: Arnd Bergmann Cc: linuxppc-dev@ozlabs.org, cel , cbe-oss-dev@ozlabs.org, linux-kernel In-Reply-To: <200808081526.21405.arnd@arndb.de> References: <1217620879.15667.145.camel@carll-linux-desktop> <200808081526.21405.arnd@arndb.de> Content-Type: text/plain Date: Fri, 08 Aug 2008 15:39:44 -0700 Message-Id: <1218235184.6637.111.camel@carll-linux-desktop> Mime-Version: 1.0 X-Mailer: Evolution 2.12.1 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Updated to address Arnd's comments. If an error occurs on opcontrol start, the event and per cpu buffers are released. If later opcontrol shutdown is called then the free function will be called again to free buffers that no longer exist. This results in a kernel oops. The following changes prevent the call to delete buffers that don't exist. Signed-off-by: Carl Love Index: Cell_kernel_6_26_2008/drivers/oprofile/cpu_buffer.c =================================================================== --- Cell_kernel_6_26_2008.orig/drivers/oprofile/cpu_buffer.c +++ Cell_kernel_6_26_2008/drivers/oprofile/cpu_buffer.c @@ -38,8 +38,10 @@ void free_cpu_buffers(void) { int i; - for_each_online_cpu(i) + for_each_online_cpu(i) { vfree(per_cpu(cpu_buffer, i).buffer); + per_cpu(cpu_buffer, i).buffer = NULL; + } } unsigned long oprofile_get_cpu_buffer_size(void) Index: Cell_kernel_6_26_2008/drivers/oprofile/event_buffer.c =================================================================== --- Cell_kernel_6_26_2008.orig/drivers/oprofile/event_buffer.c +++ Cell_kernel_6_26_2008/drivers/oprofile/event_buffer.c @@ -93,6 +93,8 @@ out: void free_event_buffer(void) { vfree(event_buffer); + + event_buffer = NULL; }