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=-9.0 required=3.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY,SPF_PASS,URIBL_BLOCKED, USER_AGENT_GIT autolearn=ham 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 7BDB1C282C2 for ; Thu, 7 Feb 2019 20:59:46 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 552A72175B for ; Thu, 7 Feb 2019 20:59:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727580AbfBGU7o (ORCPT ); Thu, 7 Feb 2019 15:59:44 -0500 Received: from emh01.mail.saunalahti.fi ([62.142.5.107]:59338 "EHLO emh01.mail.saunalahti.fi" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727423AbfBGU7o (ORCPT ); Thu, 7 Feb 2019 15:59:44 -0500 Received: from localhost.localdomain (85-76-102-43-nat.elisa-mobile.fi [85.76.102.43]) by emh01.mail.saunalahti.fi (Postfix) with ESMTP id AD9FF20028; Thu, 7 Feb 2019 22:59:40 +0200 (EET) From: Aaro Koskinen To: Kees Cook , Andrew Morton , linux-kernel@vger.kernel.org Cc: Aaro Koskinen Subject: [PATCH] panic/reboot: allow specifying reboot_mode for panic only Date: Thu, 7 Feb 2019 22:59:09 +0200 Message-Id: <20190207205909.28765-1-aaro.koskinen@iki.fi> X-Mailer: git-send-email 2.17.0 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: Aaro Koskinen Allow specifying reboot_mode for panic only. This is needed on systems where ramoops is used to store panic logs, and user wants to use warm reset to preserve those, while still having cold reset on normal reboots. Signed-off-by: Aaro Koskinen --- .../admin-guide/kernel-parameters.txt | 4 +++- include/linux/reboot.h | 1 + kernel/panic.c | 2 ++ kernel/reboot.c | 20 ++++++++++++++----- 4 files changed, 21 insertions(+), 6 deletions(-) diff --git a/Documentation/admin-guide/kernel-parameters.txt b/Documentation/admin-guide/kernel-parameters.txt index b799bcf67d7b..033c93048a95 100644 --- a/Documentation/admin-guide/kernel-parameters.txt +++ b/Documentation/admin-guide/kernel-parameters.txt @@ -3950,7 +3950,9 @@ [[,]s[mp]#### \ [[,]b[ios] | a[cpi] | k[bd] | t[riple] | e[fi] | p[ci]] \ [[,]f[orce] - Where reboot_mode is one of warm (soft) or cold (hard) or gpio, + Where reboot_mode is one of warm (soft) or cold (hard) or gpio + (prefix with 'panic_' to set mode for panic + reboot only), reboot_type is one of bios, acpi, kbd, triple, efi, or pci, reboot_force is either force or not specified, reboot_cpu is s[mp]#### with #### being the processor diff --git a/include/linux/reboot.h b/include/linux/reboot.h index e63799a6e895..61962f9826fa 100644 --- a/include/linux/reboot.h +++ b/include/linux/reboot.h @@ -21,6 +21,7 @@ enum reboot_mode { REBOOT_GPIO, }; extern enum reboot_mode reboot_mode; +extern enum reboot_mode panic_reboot_mode; enum reboot_type { BOOT_TRIPLE = 't', diff --git a/kernel/panic.c b/kernel/panic.c index f121e6ba7e11..c4285e3a27ef 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -306,6 +306,8 @@ void panic(const char *fmt, ...) * shutting down. But if there is a chance of * rebooting the system it will be rebooted. */ + if (panic_reboot_mode != -1) + reboot_mode = panic_reboot_mode; emergency_restart(); } #ifdef __sparc__ diff --git a/kernel/reboot.c b/kernel/reboot.c index e1b79b6a2735..d5627a92508d 100644 --- a/kernel/reboot.c +++ b/kernel/reboot.c @@ -31,6 +31,7 @@ EXPORT_SYMBOL(cad_pid); #define DEFAULT_REBOOT_MODE #endif enum reboot_mode reboot_mode DEFAULT_REBOOT_MODE; +enum reboot_mode panic_reboot_mode = -1; /* * This variable is used privately to keep track of whether or not @@ -519,6 +520,8 @@ EXPORT_SYMBOL_GPL(orderly_reboot); static int __init reboot_setup(char *str) { for (;;) { + enum reboot_mode *mode; + /* * Having anything passed on the command line via * reboot= will cause us to disable DMI checking @@ -526,17 +529,24 @@ static int __init reboot_setup(char *str) */ reboot_default = 0; + if (!strncmp(str, "panic_", 6)) { + mode = &panic_reboot_mode; + str += 6; + } else { + mode = &reboot_mode; + } + switch (*str) { case 'w': - reboot_mode = REBOOT_WARM; + *mode = REBOOT_WARM; break; case 'c': - reboot_mode = REBOOT_COLD; + *mode = REBOOT_COLD; break; case 'h': - reboot_mode = REBOOT_HARD; + *mode = REBOOT_HARD; break; case 's': @@ -553,11 +563,11 @@ static int __init reboot_setup(char *str) if (rc) return rc; } else - reboot_mode = REBOOT_SOFT; + *mode = REBOOT_SOFT; break; } case 'g': - reboot_mode = REBOOT_GPIO; + *mode = REBOOT_GPIO; break; case 'b': -- 2.17.0