> This patch will taint the kernel with a new flag, 'W', whenever a
> warning is issued with WARN_ON(condition). Whenever a warning occurs, it
> is helpful to record this within the kernel state as a taint. When a BUG
> happens, it'd be useful to know if it was also preceded by a WARN.
>
> This patch applies to Linus's git tree.
>
> Signed-off-by: Nur Hussein (
nurhussein@gmail.com)
> ---
>
> diff --git a/include/asm-generic/bug.h b/include/asm-generic/bug.h
> index 2632328..0633e96 100644
> --- a/include/asm-generic/bug.h
> +++ b/include/asm-generic/bug.h
> @@ -42,8 +42,10 @@ extern void warn_on_slowpath(const char *file, const int line);
> #ifndef WARN_ON
> #define WARN_ON(condition) ({ \
> int __ret_warn_on = !!(condition); \
> - if (unlikely(__ret_warn_on)) \
> + if (unlikely(__ret_warn_on)) { \
> __WARN(); \
> + add_taint(TAINT_WARN); \
> + } \
> unlikely(__ret_warn_on); \
> })
> #endif
> @@ -60,6 +62,8 @@ extern void warn_on_slowpath(const char *file, const int line);
> #ifndef HAVE_ARCH_WARN_ON
> #define WARN_ON(condition) ({ \
> int __ret_warn_on = !!(condition); \
> + if (unlikely(__ret_warn_on)) \
> + add_taint(TAINT_WARN); \
> unlikely(__ret_warn_on); \
> })
> #endif
> diff --git a/include/linux/kernel.h b/include/linux/kernel.h
> index 2df44e7..d90c1a4 100644
> --- a/include/linux/kernel.h
> +++ b/include/linux/kernel.h
> @@ -255,6 +255,7 @@ extern enum system_states {
> #define TAINT_USER (1<<6)
> #define TAINT_DIE (1<<7)
> #define TAINT_OVERRIDDEN_ACPI_TABLE (1<<8)
> +#define TAINT_WARN (1<<9)
>
> extern void dump_stack(void) __cold;
>
> diff --git a/kernel/panic.c b/kernel/panic.c
> index 24af9f8..e113a85 100644
> --- a/kernel/panic.c
> +++ b/kernel/panic.c
> @@ -153,6 +153,8 @@ EXPORT_SYMBOL(panic);
> * 'M' - System experienced a machine check exception.
> * 'B' - System has hit bad_page.
> * 'U' - Userspace-defined naughtiness.
> + * 'A' - ACPI table overridden.
> + * 'W' - Taint on warning.
> *