From: Marco Elver <elver@xxxxxxxxxx> Subject: panic: use error_report_end tracepoint on warnings Introduce the error detector "warning" to the error_report event and use the error_report_end tracepoint at the end of a warning report. This allows in-kernel tests but also userspace to more easily determine if a warning occurred without polling kernel logs. [akpm@xxxxxxxxxxxxxxxxxxxx: add comma to enum list, per Andy] Link: https://lkml.kernel.org/r/20211115085630.1756817-1-elver@xxxxxxxxxx Signed-off-by: Marco Elver <elver@xxxxxxxxxx> Cc: Steven Rostedt <rostedt@xxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Alexander Potapenko <glider@xxxxxxxxxx> Cc: Petr Mladek <pmladek@xxxxxxxx> Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx> Cc: Wei Liu <wei.liu@xxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxx> Cc: Arnd Bergmann <arnd@xxxxxxxx> Cc: John Ogness <john.ogness@xxxxxxxxxxxxx> Cc: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx> Cc: Alexander Popov <alex.popov@xxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/trace/events/error_report.h | 8 +++++--- kernel/panic.c | 2 ++ 2 files changed, 7 insertions(+), 3 deletions(-) --- a/include/trace/events/error_report.h~panic-use-error_report_end-tracepoint-on-warnings +++ a/include/trace/events/error_report.h @@ -17,14 +17,16 @@ enum error_detector { ERROR_DETECTOR_KFENCE, - ERROR_DETECTOR_KASAN + ERROR_DETECTOR_KASAN, + ERROR_DETECTOR_WARN, }; #endif /* __ERROR_REPORT_DECLARE_TRACE_ENUMS_ONCE_ONLY */ -#define error_detector_list \ +#define error_detector_list \ EM(ERROR_DETECTOR_KFENCE, "kfence") \ - EMe(ERROR_DETECTOR_KASAN, "kasan") + EM(ERROR_DETECTOR_KASAN, "kasan") \ + EMe(ERROR_DETECTOR_WARN, "warning") /* Always end the list with an EMe. */ #undef EM --- a/kernel/panic.c~panic-use-error_report_end-tracepoint-on-warnings +++ a/kernel/panic.c @@ -32,6 +32,7 @@ #include <linux/bug.h> #include <linux/ratelimit.h> #include <linux/debugfs.h> +#include <trace/events/error_report.h> #include <asm/sections.h> #define PANIC_TIMER_STEP 100 @@ -609,6 +610,7 @@ void __warn(const char *file, int line, print_irqtrace_events(current); print_oops_end_marker(); + trace_error_report_end(ERROR_DETECTOR_WARN, (unsigned long)caller); /* Just a warning, don't kill lockdep. */ add_taint(taint, LOCKDEP_STILL_OK); _
