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.
*
* 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");
--
