The patch titled
Taint kernel after WARN_ON(condition)
has been added to the -mm tree. Its filename is
taint-kernel-after-warn_oncondition.patch
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*** Remember to use Documentation/SubmitChecklist when testing your code ***
See http://www.zip.com.au/~akpm/linux/patches/stuff/added-to-mm.txt to find
out what to do about this
The current -mm tree may be found at http://userweb.kernel.org/~akpm/mmotm/
------------------------------------------------------
Subject: Taint kernel after WARN_ON(condition)
From: Nur Hussein <nurhussein@xxxxxxxxx>
The kernel is sent to tainted within the warn_on_slowpath() function, and
whenever a warning occurs the new taint flag 'W' is set. This is useful to
know if a warning occurred before a BUG by preserving the warning as a flag
in the taint state.
This does not work on architectures where WARN_ON has its own definition.
These archs are:
1. s390
2. superh
3. avr32
4. parisc
The maintainers of these architectures have been added in the Cc: list
in this email to alert them to the situation.
The documentation in oops-tracing.txt has been updated to include the
new flag.
Signed-off-by: Nur Hussein <nurhussein@xxxxxxxxx>
Cc: Arjan van de Ven <arjan@xxxxxxxxxxxxx>
Cc: "Randy.Dunlap" <rdunlap@xxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxx>
Cc: Peter Zijlstra <a.p.zijlstra@xxxxxxxxx>
Cc: Kyle McMartin <kyle@xxxxxxxxxxx>
Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx>
Cc: Haavard Skinnemoen <hskinnemoen@xxxxxxxxx>
Cc: Paul Mundt <lethal@xxxxxxxxxxxx>
Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx>
---
Documentation/oops-tracing.txt | 4 ++++
include/linux/kernel.h | 1 +
kernel/panic.c | 8 ++++++--
3 files changed, 11 insertions(+), 2 deletions(-)
diff -puN Documentation/oops-tracing.txt~taint-kernel-after-warn_oncondition Documentation/oops-tracing.txt
--- a/Documentation/oops-tracing.txt~taint-kernel-after-warn_oncondition
+++ a/Documentation/oops-tracing.txt
@@ -253,6 +253,10 @@ characters, each representing a particul
8: 'D' if the kernel has died recently, i.e. there was an OOPS or BUG.
+ 9: 'A' if the ACPI table has been overridden.
+
+ 10: 'W' if a warning has previously been issued by the kernel.
+
The primary reason for the 'Tainted: ' string is to tell kernel
debuggers if this is a clean kernel or if anything unusual has
occurred. Tainting is permanent: even if an offending module is
diff -puN include/linux/kernel.h~taint-kernel-after-warn_oncondition include/linux/kernel.h
--- a/include/linux/kernel.h~taint-kernel-after-warn_oncondition
+++ a/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 -puN kernel/panic.c~taint-kernel-after-warn_oncondition kernel/panic.c
--- a/kernel/panic.c~taint-kernel-after-warn_oncondition
+++ a/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");
@@ -312,6 +315,7 @@ void warn_on_slowpath(const char *file,
print_modules();
dump_stack();
print_oops_end_marker();
+ add_taint(TAINT_WARN);
}
EXPORT_SYMBOL(warn_on_slowpath);
#endif
_
Patches currently in -mm which might be from nurhussein@xxxxxxxxx are
taint-kernel-after-warn_oncondition.patch
-
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