Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758098AbYAYOy5 (ORCPT ); Fri, 25 Jan 2008 09:54:57 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1752320AbYAYOyu (ORCPT ); Fri, 25 Jan 2008 09:54:50 -0500 Received: from moutng.kundenserver.de ([212.227.126.188]:59301 "EHLO moutng.kundenserver.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752659AbYAYOyt (ORCPT ); Fri, 25 Jan 2008 09:54:49 -0500 Date: Fri, 25 Jan 2008 15:54:42 +0100 (CET) From: Bodo Eggert <7eggert@gmx.de> To: linux-kernel@vger.kernel.org Subject: [PATCH] Introduce softpanic Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=us-ascii X-be10.7eggert.dyndns.org-MailScanner-Information: See www.mailscanner.info for information X-be10.7eggert.dyndns.org-MailScanner: Found to be clean X-be10.7eggert.dyndns.org-MailScanner-From: 7eggert@gmx.de X-Provags-ID: V01U2FsdGVkX181fsUNaTldemhsHPgtJR3C/4HDQ7YDBEjtFtS pwbeoIKx0FWa+xXu1hrb1hCCuHLapXfebksnOyaRf5JvwKEF+4 cwll9lmK+M1q8G33ZPy9w== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5460 Lines: 160 Enabling this option changes a hard panic on boot errors to a soft panic, which does not stop the system completely. You can still scroll the screen and read the messages. Signed-Off-By: Bodo Eggert <7eggert@gmx.de> diff -pruN -X dontdiff linux-2.6.24.pure/include/linux/kernel.h linux-2.6.24.softpanic/include/linux/kernel.h --- linux-2.6.24.pure/include/linux/kernel.h 2008-01-25 15:09:36.000000000 +0100 +++ linux-2.6.24.softpanic/include/linux/kernel.h 2008-01-25 15:31:26.000000000 +0100 @@ -130,6 +130,12 @@ extern struct atomic_notifier_head panic extern long (*panic_blink)(long time); NORET_TYPE void panic(const char * fmt, ...) __attribute__ ((NORET_AND format (printf, 1, 2))) __cold; +#ifdef SOFTPANIC +NORET_TYPE void softpanic(const char *fmt, ...) + __attribute__ ((NORET_AND format (printf, 1, 2))) __cold; +#else +# define softpanic(...) do { panic(__VA_ARGS__); } while (0) +#endif extern void oops_enter(void); extern void oops_exit(void); extern int oops_may_print(void); diff -pruN -X dontdiff linux-2.6.24.pure/init/Kconfig linux-2.6.24.softpanic/init/Kconfig --- linux-2.6.24.pure/init/Kconfig 2008-01-25 15:09:38.000000000 +0100 +++ linux-2.6.24.softpanic/init/Kconfig 2008-01-25 15:15:08.000000000 +0100 @@ -526,6 +526,14 @@ config BUG option for embedded systems with no facilities for reporting errors. Just say Y. +config SOFTPANIC + bool "Enable softpanic for boot errors" if EMBEDDED + default y + help + Enabling this option changes a hard panic on boot errors to a + soft panic, which does not stop the system completely. + You can still scroll the screen and read the messages. + config ELF_CORE default y bool "Enable ELF core dumps" if EMBEDDED diff -pruN -X dontdiff linux-2.6.24.pure/init/do_mounts.c linux-2.6.24.softpanic/init/do_mounts.c --- linux-2.6.24.pure/init/do_mounts.c 2008-01-25 15:08:31.000000000 +0100 +++ linux-2.6.24.softpanic/init/do_mounts.c 2008-01-25 15:15:08.000000000 +0100 @@ -330,7 +330,7 @@ retry: printk("Please append a correct \"root=\" boot option; here are the available partitions:\n"); printk_all_partitions(); - panic("VFS: Unable to mount root fs on %s", b); + softpanic("VFS: Unable to mount root fs on %s", b); } printk("List of all partitions:\n"); @@ -342,7 +342,7 @@ retry: #ifdef CONFIG_BLOCK __bdevname(ROOT_DEV, b); #endif - panic("VFS: Unable to mount root fs on %s", b); + softpanic("VFS: Unable to mount root fs on %s", b); out: putname(fs_names); } diff -pruN -X dontdiff linux-2.6.24.pure/init/main.c linux-2.6.24.softpanic/init/main.c --- linux-2.6.24.pure/init/main.c 2008-01-25 15:09:38.000000000 +0100 +++ linux-2.6.24.softpanic/init/main.c 2008-01-25 15:15:08.000000000 +0100 @@ -585,7 +585,7 @@ asmlinkage void __init start_kernel(void */ console_init(); if (panic_later) - panic(panic_later, panic_param); + softpanic(panic_later, panic_param); lockdep_info(); @@ -800,7 +800,7 @@ static int noinline init_post(void) run_init_process("/bin/init"); run_init_process("/bin/sh"); - panic("No init found. Try passing init= option to kernel."); + softpanic("No init found. Try passing init= option to kernel."); } static int __init kernel_init(void * unused) diff -pruN -X dontdiff linux-2.6.24.pure/kernel/panic.c linux-2.6.24.softpanic/kernel/panic.c --- linux-2.6.24.pure/kernel/panic.c 2008-01-25 15:09:38.000000000 +0100 +++ linux-2.6.24.softpanic/kernel/panic.c 2008-01-25 15:38:52.000000000 +0100 @@ -142,6 +142,66 @@ NORET_TYPE void panic(const char * fmt, EXPORT_SYMBOL(panic); +#ifdef SOFTPANIC +NORET_TYPE void softpanic(const char *fmt, ...) +{ + long i; + static char buf[1024]; + va_list args; +#if defined(CONFIG_S390) + unsigned long caller = (unsigned long) __builtin_return_address(0); +#endif + + va_start(args, fmt); + vsnprintf(buf, sizeof(buf), fmt, args); + va_end(args); + printk(KERN_EMERG "Kernel panic - not syncing: %s\n", buf); + + atomic_notifier_call_chain(&panic_notifier_list, 0, buf); + + if (!panic_blink) + panic_blink = no_blink; + + if (panic_timeout > 0) { + /* + * Delay timeout seconds before rebooting the machine. + * We can't use the "normal" timers since we just panicked.. + */ + printk(KERN_EMERG "Rebooting in %d seconds..", panic_timeout); + for (i = 0; i < panic_timeout*1000; ) { + touch_nmi_watchdog(); + i += panic_blink(i); + mdelay(1); + i++; + } + /* This will not be a clean reboot, with everything + * shutting down. But if there is a chance of + * rebooting the system it will be rebooted. + */ + kernel_restart(NULL); + } +#ifdef __sparc__ + { + extern int stop_a_enabled; + /* Make sure the user can actually press Stop-A (L1-A) */ + stop_a_enabled = 1; + printk(KERN_EMERG + "Press Stop-A (L1-A) to return to the boot prom\n"); + } +#endif +#if defined(CONFIG_S390) + disabled_wait(caller); +#endif + for (i = 0;;) { + touch_softlockup_watchdog(); + i += panic_blink(i); + msleep(1); + i++; + } +} +EXPORT_SYMBOL(softpanic); +#endif + /** * print_tainted - return a string to represent the kernel taint state. * -- Top 100 things you don't want the sysadmin to say: 21. where did you say those backup tapes were kept? -- 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/