Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753173AbbG0FLP (ORCPT ); Mon, 27 Jul 2015 01:11:15 -0400 Received: from mail9.hitachi.co.jp ([133.145.228.44]:58451 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751388AbbG0FLN (ORCPT ); Mon, 27 Jul 2015 01:11:13 -0400 X-AuditID: 85900ec0-9d7c9b9000001a57-74-55b5bd363d43 X-Mailbox-Line: From nobody Mon Jul 27 10:58:50 2015 Subject: [V2 PATCH 0/3] x86: Fix panic vs. NMI issues To: Jonathan Corbet , Peter Zijlstra , Ingo Molnar , "Eric W. Biederman" , "H. Peter Anvin" , Andrew Morton , Thomas Gleixner , Vivek Goyal From: Hidehiro Kawai Cc: linux-doc@vger.kernel.org, x86@kernel.org, kexec@lists.infradead.org, linux-kernel@vger.kernel.org, Michal Hocko , Masami Hiramatsu Date: Mon, 27 Jul 2015 10:58:50 +0900 Message-ID: <20150727015850.4928.87717.stgit@softrs> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1598 Lines: 44 When an HA cluster software or administrator detects non-response of a host, they issue an NMI to the host to completely stop current works and take a crash dump. If the kernel has already panicked or is capturing a crash dump at that time, further NMI can cause a crash dump failure. To solve this issue, this patch set does two things: - Don't panic on NMI if the kernel has already panicked - Introduce "noextnmi" boot option which masks external NMI at the boot time (supported only for x86) V2: - Use atomic_cmpxchg() instead of current spin_trylock() to exclude concurrent accesses to panic() and crash_kexec() - Don't introduce no-lock version of panic() and crash_kexec() --- Hidehiro Kawai (3): x86/panic: Fix re-entrance problem due to panic on NMI kexec: Fix race between panic() and crash_kexec() called directly x86/apic: Introduce noextnmi boot option Documentation/kernel-parameters.txt | 4 ++++ arch/x86/kernel/apic/apic.c | 17 ++++++++++++++++- arch/x86/kernel/nmi.c | 15 +++++++++++---- include/linux/kernel.h | 1 + kernel/kexec.c | 20 ++++++++++++++++++++ kernel/panic.c | 13 ++++++++++--- 6 files changed, 62 insertions(+), 8 deletions(-) -- Hidehiro Kawai Hitachi, Ltd. Research & Development Group -- 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/