I can confirm, after patch this issue never appeared again. So maybe
good to push it to stable and etc :) Thanks a lot Eric, you saved me
again.
Still i have some weird panic issues, maybe related to conntrack, but
they are rare even on high load, so i am slowly gathering data, and i
found at least one more person with similar conntrack crashes on latest
kernels.
On 2015-11-04 06:46, Eric Dumazet wrote:
On Wed, 2015-11-04 at 06:25 +0200, Denys Fedoryshchenko wrote:
On 2015-11-04 00:06, Cong Wang wrote:
> On Mon, Nov 2, 2015 at 6:11 AM, Denys Fedoryshchenko
> <nuclear...@nuclearcat.com> wrote:
>> Hi!
>>
>> Actually seems i was getting this panic for a while (once per week) on
>> loaded pppoe server, but just now was able to get full panic message.
>> After checking commit logs on sch_fq.c i didnt seen any fixes, so
>> probably
>> upgrading to newer kernel wont help?
>
>
> Can you share your `tc qdisc show dev xxxx` with us? And how to
> reproduce
> it? I tried to setup htb+fq and then flip the interface back and forth
> but I don't
> see any crash.
My guess it wont be easy to reproduce, it is happening on box with
4.5k
interfaces, that constantly create/delete interfaces,
and even with that this problem may happen once per day, or may not
happen for 1 week.
Here is script that is being fired after new ppp interface detected.
But
pppoe process are independent from
process that are "establishing" shapers.
It is probably a generic bug. sch_fq seems OK to me.
Somehow nobody tries to change qdisc hundred times per second ;)
Could you try following patch ?
It seems to 'fix' the issue for me.
diff --git a/net/core/dev.c b/net/core/dev.c
index 8ce3f74cd6b9..bf136103bc7b 100644
--- a/net/core/dev.c
+++ b/net/core/dev.c
@@ -2880,6 +2880,12 @@ static inline int __dev_xmit_skb(struct sk_buff
*skb, struct Qdisc *q,
spin_lock(&q->busylock);
spin_lock(root_lock);
+ if (unlikely(q != rcu_dereference_bh(txq->qdisc))) {
+ pr_err_ratelimited("Arg, qdisc changed ! state %lx\n",
q->state);
+ kfree_skb(skb);
+ rc = NET_XMIT_DROP;
+ goto end;
+ }
if (unlikely(test_bit(__QDISC_STATE_DEACTIVATED, &q->state))) {
kfree_skb(skb);
rc = NET_XMIT_DROP;
@@ -2913,6 +2919,7 @@ static inline int __dev_xmit_skb(struct sk_buff
*skb, struct Qdisc *q,
__qdisc_run(q);
}
}
+end:
spin_unlock(root_lock);
if (unlikely(contended))
spin_unlock(&q->busylock);
--
To unsubscribe from this list: send the line "unsubscribe netdev" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
