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:
[<ffffffff81c614dc>] dump_stack+0x19/0x1b
[<ffffffff8108f500>] warn_slowpath_common+0x70/0xa0
[<ffffffff8108f54a>] warn_slowpath_null+0x1a/0x20
[<ffffffff8234a0c3>] 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 <tj@kernel.org>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Fengguang Wu <fengguang.wu@intel.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jesper Nilsson <jesper.nilsson@axis.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Mike Frysinger <vapier@gentoo.org>
Cc: Vineet Gupta <vgupta@synopsys.com>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
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 @@
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 @@
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 @@
}
/**
+ * 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 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 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 @@
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 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..167ec097 100644
--- a/kernel/panic.c
+++ b/kernel/panic.c
@@ -22,7 +22,6 @@
#include <linux/sysrq.h>
#include <linux/init.h>
#include <linux/nmi.h>
-#include <linux/dmi.h>
#define PANIC_TIMER_STEP 100
#define PANIC_BLINK_SPD 18
@@ -400,13 +399,8 @@
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 @@
}
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 @@
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