On Tue, Oct 31, 2017 at 2:55 PM, Lucas Bates [off-list ref] wrote:

On Tue, Oct 31, 2017 at 7:00 AM, Jamal Hadi Salim [off-list ref] wrote:

quoted

On 17-10-31 01:44 AM, Cong Wang wrote:

quoted

Can you try this patch? From your stack trace it is not clear where
the cause is, but we know that the crash is in __tcf_idr_release(),
this is how I came up with the following patch:

diff --git a/include/net/act_api.h b/include/net/act_api.h
index b944e0eb93be..5072446d5f06 100644
--- a/include/net/act_api.h
+++ b/include/net/act_api.h

@@ -122,7 +122,9 @@ void tcf_idrinfo_destroy(const struct tc_action_ops

*ops,

  static inline void tc_action_net_exit(struct tc_action_net *tn)
  {
+       rtnl_lock();
         tcf_idrinfo_destroy(tn->ops, tn->idrinfo);
+       rtnl_unlock();
         kfree(tn->idrinfo);
  }

Looks like an excellent bet;-> tdc kills the container at the end of the
test.

Unfortunately it doesn't seem to have had any effect, I'm still seeing
the same bug as yesterday. At Jamal's suggestion I put in a delay
after tdc completed running the tests but before it deleted the
container - and I didn't run into the bug after many runs. I had no
luck getting serial console access on any of our other systems so I
have another stack trace photo which I'll send to you directly.

I forgot to mention: it appears the bug appears to be related to
deleting the container. Test d052 is the last to run before tdc does
its teardown and deletes the container; if I add the sleep the bug
never gets triggered.