[PATCH 1/2] RFC: hung_task: taint kernel

Daniel Vetter
2019-05-02T19:42:07Z

There's the hung_task_panic sysctl, but that's a bit an extreme measure.
As a fallback taint at least the machine.

Our CI uses this to decide when a reboot is necessary, plus to figure
out whether the kernel is still happy.

Signed-off-by: Daniel Vetter <daniel.vetter@intel.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: "Paul E. McKenney" <paulmck@linux.ibm.com>
Cc: Valdis Kletnieks <valdis.kletnieks@vt.edu>
Cc: Daniel Vetter <daniel.vetter@ffwll.ch>
Cc: Vitaly Kuznetsov <vkuznets@redhat.com>
Cc: "Liu, Chuansheng" <chuansheng.liu@intel.com>
---
kernel/hung_task.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/kernel/hung_task.c b/kernel/hung_task.c
index f108a95882c6..7fae16f1b49c 100644
--- a/kernel/hung_task.c
+++ b/kernel/hung_task.c
@@ -203,6 +203,8 @@ static void check_hung_uninterruptible_tasks(unsigned long timeout)
if (hung_task_call_panic) {
trigger_all_cpu_backtrace();
panic("hung_task: blocked tasks");
+ } else {
+ add_taint(TAINT_WARN, LOCKDEP_STILL_OK);
}
}

--
2.20.1