[PATCH v2] kasan: Respect /proc/sys/kernel/traceoff_on_warning

[Andrey Ryabinin]

From: Peter Zijlstra <peterz@xxxxxxxxxxxxx>

After much waiting I finally reproduced a KASAN issue, only to find my
trace-buffer empty of useful information because it got spooled out :/

Make kasan_report honour the /proc/sys/kernel/traceoff_on_warning
interface.

Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Acked-by: Alexander Potapenko <glider@xxxxxxxxxx>
Cc: Dmitry Vyukov <dvyukov@xxxxxxxxxx>
Cc: Steven Rostedt <rostedt@xxxxxxxxxxx>
Signed-off-by: Andrey Ryabinin <aryabinin@xxxxxxxxxxxxx>
---
 mm/kasan/report.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/mm/kasan/report.c b/mm/kasan/report.c
index b82b3e2..f479365 100644
--- a/mm/kasan/report.c
+++ b/mm/kasan/report.c
@@ -13,6 +13,7 @@
  *
  */
 
+#include <linux/ftrace.h>
 #include <linux/kernel.h>
 #include <linux/mm.h>
 #include <linux/printk.h>
@@ -300,6 +301,8 @@ void kasan_report(unsigned long addr, size_t size,
 	if (likely(!kasan_report_enabled()))
 		return;
 
+	disable_trace_on_warning();
+
 	info.access_addr = (void *)addr;
 	info.access_size = size;
 	info.is_write = is_write;
-- 
2.10.2