From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-3.9 required=3.0 tests=DKIMWL_WL_HIGH,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 765D9C282DD for ; Thu, 9 Jan 2020 21:55:05 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 4C0E120656 for ; Thu, 9 Jan 2020 21:55:05 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=arista.com header.i=@arista.com header.b="o37iHXGp" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729139AbgAIVzE (ORCPT ); Thu, 9 Jan 2020 16:55:04 -0500 Received: from mail-pj1-f67.google.com ([209.85.216.67]:39839 "EHLO mail-pj1-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728831AbgAIVzD (ORCPT ); Thu, 9 Jan 2020 16:55:03 -0500 Received: by mail-pj1-f67.google.com with SMTP id m1so69976pjv.4 for ; Thu, 09 Jan 2020 13:55:02 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=arista.com; s=googlenew; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=N7GVSKV4F6bNHQbtnn1xWNA8+a7ZmcRqqi6Z4aNgeGA=; b=o37iHXGp65Rk0F0pK1xFqFPpnQd/WKN5KY466a+wyzlHSoLBCsdZxrfPvUUQSLOlT8 rHhH3A+iDPu6V11/cmz+hyZ8RRAChafIntBfQm7i0/fNDXHeGI98GV+O2S93KYmpCDrG N4gJf3oYaJlKnwlSb7UsfkgcXGoK/W4wx/Pyn7uLtj00Ms5Foa4pGAqa9nJfg1kVwApW qPA49nyCy8y05IRz2dMCAelP4+0HTNB2qykTRdVa8tzMf6tQDMYeKYAfsp/m4wKqUX95 LFxXoOV4qxPkXN5Mvn16Qq2zeVY4wc87USuITxzTan5jrZrwZrd9z3Nvgb4JmEXRoGw9 V2TQ== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=N7GVSKV4F6bNHQbtnn1xWNA8+a7ZmcRqqi6Z4aNgeGA=; b=iz3CLwG0HvGxfuXTSAl+e3ZehUxffXjJtiVu+3Imc1xO3311PUy5qU1gHPMTQRlU3E H1wQ1vmkexW2FMFNa0x+8ulAbUNlE05Zg5tJ5+IN4efvNNHUHwELVdkNQRtvw3O9CaZT gR77YBN0bFM6znUiGmPTcQmU7VQo0vRgDdXJvdPPDHrzQlS7IcTv+MEMwTQzz0cSJ/Tc VU45TzzI11yKfcpnJEjLuWD419NF2AOCU5nM+2ltzUmV7RCXJP8cTWRELwv5zpvFqc8+ 0QbJxkvwhRRlmVnJZ/fs5cnNV60MtE89vXLxrUEfCgU0FHmxPw0UqImpcaIAVIZ/Bh2o VfTw== X-Gm-Message-State: APjAAAVlFFFwAYR4jcsAJ1xyNiya5F1s0Bo79SpvK4splet2BASQaJfI qSRBq1F8uyxZ5D5jhath6xzm2D4VSgM= X-Google-Smtp-Source: APXvYqzay0u4UiA0c3NMCDCn2cO+dnn7O2PaiaVMcZodtNNHJIDvBJOVl2BTM9pOsCj6E9bkX3PJEw== X-Received: by 2002:a17:902:7102:: with SMTP id a2mr99621pll.301.1578606901747; Thu, 09 Jan 2020 13:55:01 -0800 (PST) Received: from Mindolluin.ire.aristanetworks.com ([217.173.96.166]) by smtp.gmail.com with ESMTPSA id r20sm8711536pgu.89.2020.01.09.13.54.56 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 09 Jan 2020 13:55:00 -0800 (PST) From: Dmitry Safonov To: linux-kernel@vger.kernel.org Cc: Dmitry Safonov <0x7f454c46@gmail.com>, Dmitry Safonov , Greg Kroah-Hartman , Jiri Slaby , Vasiliy Khoruzhick , linux-serial@vger.kernel.org, Iurii Zaikin , Luis Chamberlain , Kees Cook , linux-fsdevel@vger.kernel.org Subject: [PATCH-next 0/3] serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE Date: Thu, 9 Jan 2020 21:54:41 +0000 Message-Id: <20200109215444.95995-1-dima@arista.com> X-Mailer: git-send-email 2.24.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Magic sysrq has proven for Arista usecases to be useful for debugging issues in field, over serial line when the switch is in such bad state that it can't accept network connections anymore. Unfortunately, having sysrq always enabled doesn't work for some embedded boards that tend to generate garbage on serial line (including BREAKs). Since commit 732dbf3a6104 ("serial: do not accept sysrq characters via serial port"), it's possible to keep sysrq enabled, but over serial line. Add a way to enable sysrq on a uart, where currently it can be constantly either on or off (CONFIG_MAGIC_SYSRQ_SERIAL). While doing so, cleanup __sysrq_enabled and serial_core header file. Sending against -next tree as it's based on removing SUPPORT_SYSRQ ifdeffery [1]. [1]: https://lkml.kernel.org/r/20191213000657.931618-1-dima@arista.com Cc: Greg Kroah-Hartman Cc: Jiri Slaby Cc: Vasiliy Khoruzhick Cc: linux-serial@vger.kernel.org Thanks, Dmitry Dmitry Safonov (3): serial_core: Move sysrq functions from header file sysctl/sysrq: Remove __sysrq_enabled copy serial/sysrq: Add MAGIC_SYSRQ_SERIAL_SEQUENCE drivers/tty/serial/serial_core.c | 123 +++++++++++++++++++++++++++++++ drivers/tty/sysrq.c | 7 ++ include/linux/serial_core.h | 86 ++------------------- include/linux/sysrq.h | 1 + kernel/sysctl.c | 41 ++++++----- lib/Kconfig.debug | 8 ++ 6 files changed, 167 insertions(+), 99 deletions(-) -- 2.24.1