From 95b570c9cef3b12356454c7112571b7e406b4b51 Mon Sep 17 00:00:00 2001 From: Nur Hussein Date: Tue, 29 Apr 2008 00:58:39 -0700 Subject: [PATCH] Taint kernel after WARN_ON(condition) 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 Cc: Arjan van de Ven Cc: "Randy.Dunlap" Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Kyle McMartin Cc: Martin Schwidefsky Cc: Haavard Skinnemoen Cc: Paul Mundt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- Documentation/oops-tracing.txt | 4 ++++ include/linux/kernel.h | 1 + kernel/panic.c | 8 ++++++-- 3 files changed, 11 insertions(+), 2 deletions(-) diff --git a/Documentation/oops-tracing.txt b/Documentation/oops-tracing.txt index 7f60dfe642ca..b152e81da592 100644 --- a/Documentation/oops-tracing.txt +++ b/Documentation/oops-tracing.txt @@ -253,6 +253,10 @@ characters, each representing a particular tainted value. 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 --git a/include/linux/kernel.h b/include/linux/kernel.h index cd6d02cf854d..28caa53dd1f7 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 24af9f8bac99..425567f45b9f 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"); @@ -312,6 +315,7 @@ void warn_on_slowpath(const char *file, int line) print_modules(); dump_stack(); print_oops_end_marker(); + add_taint(TAINT_WARN); } EXPORT_SYMBOL(warn_on_slowpath); #endif -- 2.30.2