On 2020/10/30 19:50, Joakim Tjernlund wrote:
> On Fri, 2020-10-30 at 09:36 +0800, Yunsheng Lin wrote:
>> CAUTION: This email originated from outside of the organization. Do not
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>>
>>
>> On 2020/10/29 23:18, David Ahern wrote:
>>> On 10/29/20 8:10 AM, Joakim Tjernlund wrote:
>>>> OK, bisecting (was a bit of a bother since we merge upstream releases into
>>>> our tree, is there a way to just bisect that?)
>>>>
>>>> Result was commit "net: sch_generic: aviod concurrent reset and enqueue op
>>>> for lockless qdisc" (749cc0b0c7f3dcdfe5842f998c0274e54987384f)
>>>>
>>>> Reverting that commit on top of our tree made it work again. How to fix?
>>>
>>> Adding the author of that patch ([email protected]) to take a look.
>>>
>>>
>>>>
>>>> Jocke
>>>>
>>>> On Mon, 2020-10-26 at 12:31 -0600, David Ahern wrote:
>>>>>
>>>>> On 10/26/20 6:58 AM, Joakim Tjernlund wrote:
>>>>>> Ping (maybe it should read "arping" instead :)
>>>>>>
>>>>>> Jocke
>>>>>>
>>>>>> On Thu, 2020-10-22 at 17:19 +0200, Joakim Tjernlund wrote:
>>>>>>> strace arping -q -c 1 -b -U -I eth1 0.0.0.0
>>>>>>> ...
>>>>>>> sendto(3, "\0\1\10\0\6\4\0\1\0\6\234\v\6
>>>>>>> \v\v\v\v\377\377\377\377\377\377\0\0\0\0", 28, 0, {sa_family=AF_PACKET,
>>>>>>> proto=0x806, if4, pkttype=PACKET_HOST, addr(6)={1, ffffffffffff},
>>>>>>> 20) = -1 ENOBUFS (No buffer space available)
>>>>>>> ....
>>>>>>> and then arping loops.
>>>>>>>
>>>>>>> in 4.19.127 it was:
>>>>>>> sendto(3,
>>>>>>> "\0\1\10\0\6\4\0\1\0\6\234\5\271\362\n\322\212E\377\377\377\377\377\377\0\0\0\0",
>>>>>>> 28, 0, {​sa_family=AF_PACKET, proto=0x806, if4, pkttype=PACKET_HOST,
>>>>>>> addr(6)={​1,
>>>>>>> ffffffffffff}​, 20) = 28
>>>>>>>
>>>>>>> Seems like something has changed the IP behaviour between now and then ?
>>>>>>> eth1 is UP but not RUNNING and has an IP address.
>>
>> "eth1 is UP but not RUNNING" usually mean user has configure the netdev as
>> up,
>> but the hardware has not detected a linkup yet.
>>
>> Also What is the output of "ethtool eth1"?
>
> echo 1 > /sys/class/net/eth1/carrier
> cu3-jocke ~ # arping -q -c 1 -b -U -I eth1 0.0.0.0
> cu3-jocke ~ # echo 0 > /sys/class/net/eth1/carrier
> cu3-jocke ~ # arping -q -c 1 -b -U -I eth1 0.0.0.0
> ^Ccu3-jocke ~ # ethtool eth1
> Settings for eth1:
> Supported ports: [ MII ]
> Supported link modes: 1000baseT/Full
> Supported pause frame use: Symmetric Receive-only
> Supports auto-negotiation: Yes
> Advertised link modes: 1000baseT/Full
> Advertised pause frame use: Symmetric Receive-only
> Advertised auto-negotiation: Yes
> Speed: 10Mb/s
> Duplex: Half
> Port: MII
> PHYAD: 1
> Transceiver: external
> Auto-negotiation: on
> Current message level: 0x00000037 (55)
> drv probe link ifdown ifup
> Link detected: no
>
> We have a writeable carrier since eth device is PHY less. Maybe that path is
> different ?
> Check drivers/net/ethernet/freescale/dpaa/dpa_eth.c
The above difference does not seems to matter.
>
>>
>> It would be good to see the status of netdev before and after executing
>> arping cmd
>> too.
>
> hmm, how do you mean?
I was trying to find out when the netdev' state became "eth1 is UP but not
RUNNING".
Anyway, when I looked at the backported patch, I did find new qdisc assignment
is
missing from the upstream patch.
Please see if the below patch fix your problem, thanks:
diff --git a/net/sched/sch_generic.c b/net/sched/sch_generic.c
index bd96fd2..4e15913 100644
--- a/net/sched/sch_generic.c
+++ b/net/sched/sch_generic.c
@@ -1116,10 +1116,13 @@ static void dev_deactivate_queue(struct net_device *dev,
void *_qdisc_default)
{
struct Qdisc *qdisc = rtnl_dereference(dev_queue->qdisc);
+ struct Qdisc *qdisc_default = _qdisc_default;
if (qdisc) {
if (!(qdisc->flags & TCQ_F_BUILTIN))
set_bit(__QDISC_STATE_DEACTIVATED, &qdisc->state);
+
+ rcu_assign_pointer(dev_queue->qdisc, qdisc_default);
}
}
>
>>
>> Thanks.
>>
>>>>>>>
>>>>>>> Jocke
>>>>>>
>>>>>
>>>>> do a git bisect between the releases to find out which commit is causing
>>>>> the change in behavior.
>>
>> unfortunately, I did not reproduce the above problem in 4.19.150 too.
>>
>> root@(none)$ arping -q -c 1 -b -U -I eth0 0.0.0.0
>> root@(none)$ arping -v
>> ARPing 2.21, by Thomas Habets <[email protected]>
>> usage: arping [ -0aAbdDeFpPqrRuUv ] [ -w <sec> ] [ -W <sec> ] [ -S <host/ip>
>> ]
>> [ -T <host/ip ] [ -s <MAC> ] [ -t <MAC> ] [ -c <count> ]
>> [ -C <count> ] [ -i <interface> ] [ -m <type> ] [ -g <group> ]
>> [ -V <vlan> ] [ -Q <priority> ] <host/ip/MAC | -B>
>> For complete usage info, use --help or check the manpage.
>> root@(none)$ cat /proc/version
>> Linux version 4.19.150 (linyunsheng@ubuntu) (gcc version 5.4.0 20160609
>> (Ubuntu/Linaro 5.4.0-6ubuntu1~16.04.12)) #4 SMP PREEMPT Fri Oct 30 09:22:06
>> CST 2020
>>
>>
>>
>>>>
>>>
>>>
>
