From 98e5e1bf722c4f976a860aed06dd365a56a34ee0 Mon Sep 17 00:00:00 2001 From: Tejun Heo Date: Tue, 30 Apr 2013 15:27:15 -0700 Subject: [PATCH] dump_stack: implement arch-specific hardware description in task dumps x86 and ia64 can acquire extra hardware identification information from DMI and print it along with task dumps; however, the usage isn't consistent. * x86 show_regs() collects vendor, product and board strings and print them out with PID, comm and utsname. Some of the information is printed again later in the same dump. * warn_slowpath_common() explicitly accesses the DMI board and prints it out with "Hardware name:" label. This applies to both x86 and ia64 but is irrelevant on all other archs. * ia64 doesn't show DMI information on other non-WARN dumps. This patch introduces arch-specific hardware description used by dump_stack(). It can be set by calling dump_stack_set_arch_desc() during boot and, if exists, printed out in a separate line with "Hardware name:" label. dmi_set_dump_stack_arch_desc() is added which sets arch-specific description from DMI data. It uses dmi_ids_string[] which is set from dmi_present() used for DMI debug message. It is superset of the information x86 show_regs() is using. The function is called from x86 and ia64 boot code right after dmi_scan_machine(). This makes the explicit DMI handling in warn_slowpath_common() unnecessary. Removed. show_regs() isn't yet converted to use generic debug information printing and this patch doesn't remove the duplicate DMI handling in x86 show_regs(). The next patch will unify show_regs() handling and remove the duplication. An example WARN dump follows. WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505() Modules linked in: CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #3 Hardware name: empty empty/S3992, BIOS 080011 10/26/2007 0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48 ffffffff8108f500 ffffffff82228240 0000000000000040 ffffffff8234a08e 0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58 Call Trace: [] dump_stack+0x19/0x1b [] warn_slowpath_common+0x70/0xa0 [] warn_slowpath_null+0x1a/0x20 [] init_workqueues+0x35/0x505 ... v2: Use the same string as the debug message from dmi_present() which also contains BIOS information. Move hardware name into its own line as warn_slowpath_common() did. This change was suggested by Bjorn Helgaas. Signed-off-by: Tejun Heo Cc: Bjorn Helgaas Cc: David S. Miller Cc: Fengguang Wu Cc: Heiko Carstens Cc: Jesper Nilsson Cc: Martin Schwidefsky Cc: Mike Frysinger Cc: Vineet Gupta Cc: Sam Ravnborg Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- arch/ia64/kernel/setup.c | 1 + arch/x86/kernel/setup.c | 1 + drivers/firmware/dmi_scan.c | 13 +++++++++++++ include/linux/dmi.h | 2 ++ include/linux/printk.h | 5 +++++ kernel/panic.c | 6 ------ kernel/printk.c | 26 ++++++++++++++++++++++++++ 7 files changed, 48 insertions(+), 6 deletions(-) diff --git a/arch/ia64/kernel/setup.c b/arch/ia64/kernel/setup.c index 2029cc0..13bfdd2 100644 --- a/arch/ia64/kernel/setup.c +++ b/arch/ia64/kernel/setup.c @@ -1063,6 +1063,7 @@ check_bugs (void) static int __init run_dmi_scan(void) { dmi_scan_machine(); + dmi_set_dump_stack_arch_desc(); return 0; } core_initcall(run_dmi_scan); diff --git a/arch/x86/kernel/setup.c b/arch/x86/kernel/setup.c index 4689855..56f7fcf 100644 --- a/arch/x86/kernel/setup.c +++ b/arch/x86/kernel/setup.c @@ -996,6 +996,7 @@ void __init setup_arch(char **cmdline_p) efi_init(); dmi_scan_machine(); + dmi_set_dump_stack_arch_desc(); /* * VMware detection requires dmi to be available, so this diff --git a/drivers/firmware/dmi_scan.c b/drivers/firmware/dmi_scan.c index 862b1d2..98c62081 100644 --- a/drivers/firmware/dmi_scan.c +++ b/drivers/firmware/dmi_scan.c @@ -531,6 +531,19 @@ void __init dmi_scan_machine(void) } /** + * dmi_set_dump_stack_arch_desc - set arch description for dump_stack() + * + * Invoke dump_stack_set_arch_desc() with DMI system information so that + * DMI identifiers are printed out on task dumps. Arch boot code should + * call this function after dmi_scan_machine() if it wants to print out DMI + * identifiers on task dumps. + */ +void __init dmi_set_dump_stack_arch_desc(void) +{ + dump_stack_set_arch_desc("%s", dmi_ids_string); +} + +/** * dmi_matches - check if dmi_system_id structure matches system DMI data * @dmi: pointer to the dmi_system_id structure to check */ diff --git a/include/linux/dmi.h b/include/linux/dmi.h index f156cca..b6eb7a0 100644 --- a/include/linux/dmi.h +++ b/include/linux/dmi.h @@ -99,6 +99,7 @@ extern const char * dmi_get_system_info(int field); extern const struct dmi_device * dmi_find_device(int type, const char *name, const struct dmi_device *from); extern void dmi_scan_machine(void); +extern void dmi_set_dump_stack_arch_desc(void); extern bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp); extern int dmi_name_in_vendors(const char *str); extern int dmi_name_in_serial(const char *str); @@ -114,6 +115,7 @@ static inline const char * dmi_get_system_info(int field) { return NULL; } static inline const struct dmi_device * dmi_find_device(int type, const char *name, const struct dmi_device *from) { return NULL; } static inline void dmi_scan_machine(void) { return; } +static inline void dmi_set_dump_stack_arch_desc(void) { } static inline bool dmi_get_date(int field, int *yearp, int *monthp, int *dayp) { if (yearp) diff --git a/include/linux/printk.h b/include/linux/printk.h index 7ce1f87..47827c0 100644 --- a/include/linux/printk.h +++ b/include/linux/printk.h @@ -145,6 +145,7 @@ extern void wake_up_klogd(void); void log_buf_kexec_setup(void); void __init setup_log_buf(int early); +void dump_stack_set_arch_desc(const char *fmt, ...); void dump_stack_print_info(const char *log_lvl); #else static inline __printf(1, 0) @@ -184,6 +185,10 @@ static inline void setup_log_buf(int early) { } +static inline void dump_stack_set_arch_desc(const char *fmt, ...) +{ +} + static inline void dump_stack_print_info(const char *log_lvl) { } diff --git a/kernel/panic.c b/kernel/panic.c index 7c57cc9..167ec09 100644 --- a/kernel/panic.c +++ b/kernel/panic.c @@ -22,7 +22,6 @@ #include #include #include -#include #define PANIC_TIMER_STEP 100 #define PANIC_BLINK_SPD 18 @@ -400,13 +399,8 @@ struct slowpath_args { static void warn_slowpath_common(const char *file, int line, void *caller, unsigned taint, struct slowpath_args *args) { - const char *board; - printk(KERN_WARNING "------------[ cut here ]------------\n"); printk(KERN_WARNING "WARNING: at %s:%d %pS()\n", file, line, caller); - board = dmi_get_system_info(DMI_PRODUCT_NAME); - if (board) - printk(KERN_WARNING "Hardware name: %s\n", board); if (args) vprintk(args->fmt, args->args); diff --git a/kernel/printk.c b/kernel/printk.c index 70b4b94..73a96de 100644 --- a/kernel/printk.c +++ b/kernel/printk.c @@ -2851,6 +2851,28 @@ void kmsg_dump_rewind(struct kmsg_dumper *dumper) } EXPORT_SYMBOL_GPL(kmsg_dump_rewind); +static char dump_stack_arch_desc_str[128]; + +/** + * dump_stack_set_arch_desc - set arch-specific str to show with task dumps + * @fmt: printf-style format string + * @...: arguments for the format string + * + * The configured string will be printed right after utsname during task + * dumps. Usually used to add arch-specific system identifiers. If an + * arch wants to make use of such an ID string, it should initialize this + * as soon as possible during boot. + */ +void __init dump_stack_set_arch_desc(const char *fmt, ...) +{ + va_list args; + + va_start(args, fmt); + vsnprintf(dump_stack_arch_desc_str, sizeof(dump_stack_arch_desc_str), + fmt, args); + va_end(args); +} + /** * dump_stack_print_info - print generic debug info for dump_stack() * @log_lvl: log level @@ -2865,6 +2887,10 @@ void dump_stack_print_info(const char *log_lvl) print_tainted(), init_utsname()->release, (int)strcspn(init_utsname()->version, " "), init_utsname()->version); + + if (dump_stack_arch_desc_str[0] != '\0') + printk("%sHardware name: %s\n", + log_lvl, dump_stack_arch_desc_str); } #endif -- 2.7.4