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 ([email protected])
---
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.
*
* The string is overwritten by the next call to print_taint().
*/
@@ -161,7 +163,7 @@ const char *print_tainted(void)
{
static char buf[20];
if (tainted) {
- snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c%c%c%c",
+ snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c%c%c%c%c",
tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G',
tainted & TAINT_FORCED_MODULE ? 'F' : ' ',
tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
@@ -170,7 +172,8 @@ const char *print_tainted(void)
tainted & TAINT_BAD_PAGE ? 'B' : ' ',
tainted & TAINT_USER ? 'U' : ' ',
tainted & TAINT_DIE ? 'D' : ' ',
- tainted & TAINT_OVERRIDDEN_ACPI_TABLE ? 'A' : ' ');
+ tainted & TAINT_OVERRIDDEN_ACPI_TABLE ? 'A' : ' ',
+ tainted & TAINT_WARN ? 'W' : ' ');
}
else
snprintf(buf, sizeof(buf), "Not tainted");
On Tue, Feb 12, 2008 at 03:52:22AM +0800, Nur Hussein wrote:
> 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.
Any architecture that has it's own WARN_ON will not taint the kernel.
Speaking of WARN_ON...
$ git-grep "[^A-Za-z_0-9]WARN_ON(1)" | wc -l
180
Maybe making a WARN() (similar to BUG) that does an unconditional warning
(and sets the taint flag) and having a simple wrapper around it for the
conditional WARN_ON would be worth it? Hm...looks like some of the USB folks
have a #define'd WARN to something quite a bit more complex (format string,
etc.)
Josef 'Jeff' Sipek.
--
Linux, n.:
Generous programmers from around the world all join forces to help
you shoot yourself in the foot for free.
On Tue, 12 Feb 2008 03:52:22 +0800 Nur Hussein wrote:
> 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 ([email protected])
> ---
>
> 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.
> *
Oops. Both 'A' and 'W' also need to be added to
Documentation/oops-tracing.txt, please.
> * The string is overwritten by the next call to print_taint().
> */
> @@ -161,7 +163,7 @@ const char *print_tainted(void)
> {
> static char buf[20];
> if (tainted) {
> - snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c%c%c%c",
> + snprintf(buf, sizeof(buf), "Tainted: %c%c%c%c%c%c%c%c%c%c",
> tainted & TAINT_PROPRIETARY_MODULE ? 'P' : 'G',
> tainted & TAINT_FORCED_MODULE ? 'F' : ' ',
> tainted & TAINT_UNSAFE_SMP ? 'S' : ' ',
> @@ -170,7 +172,8 @@ const char *print_tainted(void)
> tainted & TAINT_BAD_PAGE ? 'B' : ' ',
> tainted & TAINT_USER ? 'U' : ' ',
> tainted & TAINT_DIE ? 'D' : ' ',
> - tainted & TAINT_OVERRIDDEN_ACPI_TABLE ? 'A' : ' ');
> + tainted & TAINT_OVERRIDDEN_ACPI_TABLE ? 'A' : ' ',
> + tainted & TAINT_WARN ? 'W' : ' ');
> }
> else
> snprintf(buf, sizeof(buf), "Not tainted");
> --
---
~Randy