dump_stack() is used for many different cases, which may require a log
level consistent with other kernel messages surrounding the dump_stack()
call. Without that, certain systems that are configured to ignore the
default level messages will miss stack traces in critical error reports.
This patch introduces dump_stack_lvl() that behaves similarly to
dump_stack(), but accepts a custom log level. The old dump_stack()
becomes equal to dump_stack_lvl(KERN_DEFAULT).
A somewhat similar patch has been proposed in 2012:
https://lore.kernel.org/lkml/
1332493269.2359.9.camel@hebo/ , but wasn't
merged.
[elver@google.com: add missing dump_stack_lvl() stub if CONFIG_PRINTK=n]
Link: https://lkml.kernel.org/r/YJ0KAM0hQev1AmWe@elver.google.com
Link: https://lkml.kernel.org/r/20210506105405.3535023-1-glider@google.com
Signed-off-by: Alexander Potapenko <glider@google.com>
Reviewed-by: Marco Elver <elver@google.com>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: he, bo <bo.he@intel.com>
Cc: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Prasad Sodagudi <psodagud@quicinc.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Sergey Senozhatsky <senozhatsky@chromium.org>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Andrey Ryabinin <ryabinin.a.a@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
__printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
void dump_stack_print_info(const char *log_lvl);
void show_regs_print_info(const char *log_lvl);
__printf(1, 2) void dump_stack_set_arch_desc(const char *fmt, ...);
void dump_stack_print_info(const char *log_lvl);
void show_regs_print_info(const char *log_lvl);
+extern asmlinkage void dump_stack_lvl(const char *log_lvl) __cold;
extern asmlinkage void dump_stack(void) __cold;
extern void printk_safe_flush(void);
extern void printk_safe_flush_on_panic(void);
extern asmlinkage void dump_stack(void) __cold;
extern void printk_safe_flush(void);
extern void printk_safe_flush_on_panic(void);
+static inline void dump_stack_lvl(const char *log_lvl)
+{
+}
+
static inline void dump_stack(void)
{
}
static inline void dump_stack(void)
{
}
dump_stack_print_info(log_lvl);
}
dump_stack_print_info(log_lvl);
}
-static void __dump_stack(void)
+static void __dump_stack(const char *log_lvl)
- dump_stack_print_info(KERN_DEFAULT);
- show_stack(NULL, NULL, KERN_DEFAULT);
+ dump_stack_print_info(log_lvl);
+ show_stack(NULL, NULL, log_lvl);
#ifdef CONFIG_SMP
static atomic_t dump_lock = ATOMIC_INIT(-1);
#ifdef CONFIG_SMP
static atomic_t dump_lock = ATOMIC_INIT(-1);
-asmlinkage __visible void dump_stack(void)
+asmlinkage __visible void dump_stack_lvl(const char *log_lvl)
{
unsigned long flags;
int was_locked;
{
unsigned long flags;
int was_locked;
if (!was_locked)
atomic_set(&dump_lock, -1);
if (!was_locked)
atomic_set(&dump_lock, -1);
local_irq_restore(flags);
}
#else
local_irq_restore(flags);
}
#else
-asmlinkage __visible void dump_stack(void)
+asmlinkage __visible void dump_stack_lvl(const char *log_lvl)
+EXPORT_SYMBOL(dump_stack_lvl);
+
+asmlinkage __visible void dump_stack(void)
+{
+ dump_stack_lvl(KERN_DEFAULT);
+}
EXPORT_SYMBOL(dump_stack);
EXPORT_SYMBOL(dump_stack);