From 04c6862c055fb687c90d9652f32c11a063df15cf Mon Sep 17 00:00:00 2001 From: Seiji Aguchi Date: Wed, 12 Jan 2011 16:59:30 -0800 Subject: [PATCH] kmsg_dump: add kmsg_dump() calls to the reboot, halt, poweroff and emergency_restart paths We need to know the reason why system rebooted in support service. However, we can't inform our customers of the reason because final messages are lost on current Linux kernel. This patch improves the situation above because the final messages are saved by adding kmsg_dump() to reboot, halt, poweroff and emergency_restart path. Signed-off-by: Seiji Aguchi Cc: David Woodhouse Cc: Marco Stornelli Reviewed-by: Artem Bityutskiy Reviewed-by: KOSAKI Motohiro Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- include/linux/kmsg_dump.h | 4 ++++ kernel/printk.c | 4 ++++ kernel/sys.c | 6 ++++++ 3 files changed, 14 insertions(+) diff --git a/include/linux/kmsg_dump.h b/include/linux/kmsg_dump.h index 24b44145a886..2a0d7d651dc3 100644 --- a/include/linux/kmsg_dump.h +++ b/include/linux/kmsg_dump.h @@ -18,6 +18,10 @@ enum kmsg_dump_reason { KMSG_DUMP_OOPS, KMSG_DUMP_PANIC, KMSG_DUMP_KEXEC, + KMSG_DUMP_RESTART, + KMSG_DUMP_HALT, + KMSG_DUMP_POWEROFF, + KMSG_DUMP_EMERG, }; /** diff --git a/kernel/printk.c b/kernel/printk.c index f64b8997fc76..0b0c9aa71e89 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -1539,6 +1539,10 @@ static const char * const kmsg_reasons[] = { [KMSG_DUMP_OOPS] = "oops", [KMSG_DUMP_PANIC] = "panic", [KMSG_DUMP_KEXEC] = "kexec", + [KMSG_DUMP_RESTART] = "restart", + [KMSG_DUMP_HALT] = "halt", + [KMSG_DUMP_POWEROFF] = "poweroff", + [KMSG_DUMP_EMERG] = "emergency_restart", }; static const char *kmsg_to_str(enum kmsg_dump_reason reason) diff --git a/kernel/sys.c b/kernel/sys.c index 2745dcdb6c6c..31b71a276b40 100644 --- a/kernel/sys.c +++ b/kernel/sys.c @@ -43,6 +43,8 @@ #include #include +#include + #include #include #include @@ -285,6 +287,7 @@ out_unlock: */ void emergency_restart(void) { + kmsg_dump(KMSG_DUMP_EMERG); machine_emergency_restart(); } EXPORT_SYMBOL_GPL(emergency_restart); @@ -312,6 +315,7 @@ void kernel_restart(char *cmd) printk(KERN_EMERG "Restarting system.\n"); else printk(KERN_EMERG "Restarting system with command '%s'.\n", cmd); + kmsg_dump(KMSG_DUMP_RESTART); machine_restart(cmd); } EXPORT_SYMBOL_GPL(kernel_restart); @@ -333,6 +337,7 @@ void kernel_halt(void) kernel_shutdown_prepare(SYSTEM_HALT); sysdev_shutdown(); printk(KERN_EMERG "System halted.\n"); + kmsg_dump(KMSG_DUMP_HALT); machine_halt(); } @@ -351,6 +356,7 @@ void kernel_power_off(void) disable_nonboot_cpus(); sysdev_shutdown(); printk(KERN_EMERG "Power down.\n"); + kmsg_dump(KMSG_DUMP_POWEROFF); machine_power_off(); } EXPORT_SYMBOL_GPL(kernel_power_off);