From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754849AbcGEMN2 (ORCPT ); Tue, 5 Jul 2016 08:13:28 -0400 Received: from fallback.hitachi.co.jp ([133.145.228.49]:60904 "EHLO mailx.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751168AbcGEMN0 (ORCPT ); Tue, 5 Jul 2016 08:13:26 -0400 X-Greylist: delayed 2194 seconds by postgrey-1.27 at vger.kernel.org; Tue, 05 Jul 2016 08:13:25 EDT Subject: [V3 PATCH 0/2] kexec: crash_kexec_post_notifiers boot option related fixes To: Andrew Morton , Dave Young , "Eric W. Biederman" , Baoquan He From: Hidehiro Kawai Cc: x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, HATAYAMA Daisuke , Masami Hiramatsu , "H. Peter Anvin" , Daniel Walker , Thomas Gleixner , Borislav Petkov , Ingo Molnar , Vivek Goyal Date: Tue, 05 Jul 2016 20:33:23 +0900 Message-ID: <20160705113323.5864.66834.stgit@softrs> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-TM-AS-GCONF: 00 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This is the update version of the patch which I posted one year ago (https://lkml.org/lkml/2015/7/23/864). Because I couldn't received positive opinions against the previous version, I had changed the approach to another one which utilizes kexec purgatory. Then I'm back here. PATCH 1/2 is a bugfix for crash_kexec_post_notifiers boot option which allows users to call panic notifiers and kmsg dumpers before kdump. When this option is enabled, smp_send_stop() is used to stop other CPUs instead of a function provided by kdump. smp_send_stop() just stops other CPUs and doesn't other things needed for kdump. So, fix it by replacing smp_send_stop() with new appropriate one, panic_smp_send_stop(). Since panic_smp_send_stop() is architecture specific and I can't simply copy from kdump routines, only x86-specific version is provided. PATCH 2/2 makes crash_kexec_post_notifiers boot option modifiable after boot. We don't need to limit it to being modifiable at boot time. Changes in V3: - Revise comments, description, and symbol names (the logic doesn't change) - Make crash_kexec_post_notifiers boot option modifiable after boot Changes in V2: https://lkml.org/lkml/2015/7/23/864 - Replace smp_send_stop() call with crash_kexec version which saves cpu states and does cleanups instead of changing execution flow - Drop a fix for Problem 1 - Drop other patches because they aren't needed anymore V1: https://lkml.org/lkml/2015/7/10/316 --- Hidehiro Kawai (2): x86/panic: Replace smp_send_stop() with kdump friendly version kexec: Use core_param for crash_kexec_post_notifiers boot option arch/x86/kernel/crash.c | 14 ++++++++---- kernel/panic.c | 56 ++++++++++++++++++++++++++++++----------------- 2 files changed, 46 insertions(+), 24 deletions(-) -- Hidehiro Kawai Hitachi, Ltd. Research & Development Group