Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754222AbbLINVc (ORCPT ); Wed, 9 Dec 2015 08:21:32 -0500 Received: from mx2.suse.de ([195.135.220.15]:56128 "EHLO mx2.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752672AbbLINV3 (ORCPT ); Wed, 9 Dec 2015 08:21:29 -0500 From: Petr Mladek To: Andrew Morton Cc: Peter Zijlstra , Steven Rostedt , Russell King , Daniel Thompson , Jiri Kosina , Ingo Molnar , Thomas Gleixner , linux-kernel@vger.kernel.org, x86@kernel.org, linux-arm-kernel@lists.infradead.org, adi-buildroot-devel@lists.sourceforge.net, linux-cris-kernel@axis.com, linux-mips@linux-mips.org, linuxppc-dev@lists.ozlabs.org, linux-s390@vger.kernel.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, Petr Mladek Subject: [PATCH v3 0/4] Cleaning printk stuff in NMI context Date: Wed, 9 Dec 2015 14:21:01 +0100 Message-Id: <1449667265-17525-1-git-send-email-pmladek@suse.com> X-Mailer: git-send-email 1.8.5.6 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2700 Lines: 75 This patch set generalizes the already existing solution for printing NMI messages. The main idea comes from Peter Zijlstra. Changes against v2: + fixed compilation problems reported by 0-day build robot + MN10300 and Xtensa architectures will get handled separately + dropped the patch that printed NMI messages directly when Oops in progress; it made the solution less reliable + made the size of the buffer configurable; use real numbers instead of PAGE_SIZE Changes against v1: + rebased on top of 4.4-rc2; there the old implementation was moved to lib/nmi_backtrace.c and used also on arm; I hope that I got the arm side correctly; I was not able to test on arm :-( + defined HAVE_NMI on arm for !CPU_V7M instead of !CPU_V7; handle_fiq_as_nmi() is called from entry-armv.S that is compiled when !CPU_V7M + defined HAVE_NMI also on mips; it calls nmi_enter() and seems to have real NMIs (or am I wrong?) + serialized backtraces when printing directly (oops_in_progress) Petr Mladek (4): printk/nmi: Generic solution for safe printk in NMI printk/nmi: Use IRQ work only when ready printk/nmi: Warn when some message has been lost in NMI context printk/nmi: Increase the size of NMI buffer and make it configurable arch/Kconfig | 7 ++ arch/arm/Kconfig | 2 + arch/arm/kernel/smp.c | 2 + arch/avr32/Kconfig | 1 + arch/blackfin/Kconfig | 1 + arch/cris/Kconfig | 1 + arch/mips/Kconfig | 1 + arch/powerpc/Kconfig | 1 + arch/s390/Kconfig | 1 + arch/sh/Kconfig | 1 + arch/sparc/Kconfig | 1 + arch/tile/Kconfig | 1 + arch/x86/Kconfig | 1 + arch/x86/kernel/apic/hw_nmi.c | 1 - include/linux/hardirq.h | 2 + include/linux/percpu.h | 3 - include/linux/printk.h | 12 ++- init/Kconfig | 27 ++++++ init/main.c | 1 + kernel/printk/Makefile | 1 + kernel/printk/nmi.c | 218 ++++++++++++++++++++++++++++++++++++++++++ kernel/printk/printk.c | 29 +++--- kernel/printk/printk.h | 55 +++++++++++ lib/nmi_backtrace.c | 89 +---------------- 24 files changed, 352 insertions(+), 107 deletions(-) create mode 100644 kernel/printk/nmi.c create mode 100644 kernel/printk/printk.h -- 1.8.5.6 -- 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/