From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752672Ab1LJGvR (ORCPT ); Sat, 10 Dec 2011 01:51:17 -0500 Received: from e23smtp02.au.ibm.com ([202.81.31.144]:54118 "EHLO e23smtp02.au.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752391Ab1LJGvO (ORCPT ); Sat, 10 Dec 2011 01:51:14 -0500 Subject: [RFC PATCH v6 07/10] fadump: Introduce cleanup routine to invalidate /proc/vmcore. To: linuxppc-dev , Linux Kernel , Benjamin Herrenschmidt From: Mahesh J Salgaonkar Cc: Amerigo Wang , Kexec-ml , Milton Miller , Haren Myneni , Randy Dunlap , "Eric W. Biederman" , Ananth Narayan , Vivek Goyal , Anton Blanchard Date: Sat, 10 Dec 2011 12:21:03 +0530 Message-ID: <20111210065103.10195.1172.stgit@mars.in.ibm.com> In-Reply-To: <20111210064301.10195.3344.stgit@mars.in.ibm.com> References: <20111210064301.10195.3344.stgit@mars.in.ibm.com> User-Agent: StGit/0.15-1-ged5e-dirty MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit x-cbid: 11120920-5490-0000-0000-0000004F7295 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Mahesh Salgaonkar With the firmware-assisted dump support we don't require a reboot when we are in second kernel after crash. The second kernel after crash is a normal kernel boot and has knowledge about entire system RAM with the page tables initialized for entire system RAM. Hence once the dump is saved to disk, we can just release the reserved memory area for general use and continue with second kernel as production kernel. Hence when we release the reserved memory that contains dump data, the '/proc/vmcore' will not be valid anymore. Hence this patch introduces a cleanup routine that invalidates and removes the /proc/vmcore file. This routine will be invoked before we release the reserved dump memory area. Signed-off-by: Mahesh Salgaonkar --- fs/proc/vmcore.c | 23 +++++++++++++++++++++++ 1 files changed, 23 insertions(+), 0 deletions(-) diff --git a/fs/proc/vmcore.c b/fs/proc/vmcore.c index b0f450a..0d5071d 100644 --- a/fs/proc/vmcore.c +++ b/fs/proc/vmcore.c @@ -700,3 +700,26 @@ static int __init vmcore_init(void) return 0; } module_init(vmcore_init) + +/* Cleanup function for vmcore module. */ +void vmcore_cleanup(void) +{ + struct list_head *pos, *next; + + if (proc_vmcore) { + remove_proc_entry(proc_vmcore->name, proc_vmcore->parent); + proc_vmcore = NULL; + } + + /* clear the vmcore list. */ + list_for_each_safe(pos, next, &vmcore_list) { + struct vmcore *m; + + m = list_entry(pos, struct vmcore, list); + list_del(&m->list); + kfree(m); + } + kfree(elfcorebuf); + elfcorebuf = NULL; +} +EXPORT_SYMBOL_GPL(vmcore_cleanup);