Re: Network issue on 3.10 rcs, bisected

[Joao Correia <joaomiguelcorreia@gmail.com>]

On Fri, May 31, 2013 at 12:13 AM, Pravin Shelar <pshelar@nicira.com> wrote:
> On Thu, May 30, 2013 at 2:14 PM, Joao Correia
> <joaomiguelcorreia@gmail.com> wrote:
>> On Thu, May 30, 2013 at 5:48 PM, Pravin Shelar <pshelar@nicira.com> wrote:
>>> On Wed, May 29, 2013 at 12:53 PM, Joao Correia
>>> <joaomiguelcorreia@gmail.com> wrote:
>>>> On Wed, May 29, 2013 at 7:59 PM, Pravin Shelar <pshelar@nicira.com> wrote:
>>>>>
>>>>> On Wed, May 29, 2013 at 4:37 AM, Joao Correia
>>>>> <joaomiguelcorreia@gmail.com> wrote:
>>>>> > Hello list
>>>>> >
>>>>> > While trying the rc's for 3.10, i've stumbled upon a problem where
>>>>> > networking does not work at all. Iptables will show packet counts going up,
>>>>> > but nothing actually reaches the programs.
>>>>> >
>>>>> > I'm running fedora under hyper-v 3 (a windows 2012 host). Only tested ipv4
>>>>> > traffic, and everything times out (ping, telnet to open ports) on both
>>>>> > directions. The networking devices come up apparently ok - has static ip
>>>>> > set, and dmesg shows no errors (although i don't have many debugging options
>>>>> > enabled).
>>>>> >
>>>>> > I bisected this, and git blames commit
>>>>> > ec5f061564238892005257c83565a0b58ec79295 (net: ill link between CSUM and SG
>>>>> > features.). I can't revert it cleanly on current rc's.
>>>>> >
>>>>> Can you also send network features set on the device?
>>>>> ethtool -k <dev>
>>>>
>>>>
>>>> As requested:
>>>> Features for eth0:
>>>> rx-checksumming: off [fixed]
>>>> tx-checksumming: off
>>>>     tx-checksum-ipv4: off [fixed]
>>>>     tx-checksum-ip-generic: off [fixed]
>>>>     tx-checksum-ipv6: off [fixed]
>>>>     tx-checksum-fcoe-crc: off [fixed]
>>>>     tx-checksum-sctp: off [fixed]
>>>> scatter-gather: on
>>>>     tx-scatter-gather: on
>>>>     tx-scatter-gather-fraglist: off [fixed]
>>>> tcp-segmentation-offload: off
>>>>     tx-tcp-segmentation: off [fixed]
>>>>     tx-tcp-ecn-segmentation: off [fixed]
>>>>     tx-tcp6-segmentation: off [fixed]
>>>> udp-fragmentation-offload: off [fixed]
>>>> generic-segmentation-offload: on
>>>> generic-receive-offload: on
>>>> large-receive-offload: off [fixed]
>>>> rx-vlan-offload: off
>>>> tx-vlan-offload: on
>>>> ntuple-filters: off [fixed]
>>>> receive-hashing: off [fixed]
>>>> highdma: off [fixed]
>>>> tx-vlan-ctag-hw-insert: on [fixed]
>>>> rx-vlan-ctag-hw-parse: off [fixed]
>>>> rx-vlan-ctag-filter: off [fixed]
>>>> tx-vlan-stag-hw-insert: off [fixed]
>>>> rx-vlan-stag-hw-parse: off [fixed]
>>>> rx-vlan-stag-filter: off [fixed]
>>>> vlan-challenged: off [fixed]
>>>> tx-lockless: off [fixed]
>>>> netns-local: off [fixed]
>>>> tx-gso-robust: off [fixed]
>>>> tx-fcoe-segmentation: off [fixed]
>>>> tx-gre-segmentation: off [fixed]
>>>> tx-udp_tnl-segmentation: off [fixed]
>>>> fcoe-mtu: off [fixed]
>>>> tx-nocache-copy: off
>>>> loopback: off [fixed]
>>>> rx-fcs: off [fixed]
>>>> rx-all: off [fixed]
>>>>
>>>> The output is similar on a working (3.9) and a bad (3.10) kernel.
>>>> diff-ing both outputs shows:
>>>> tx-vlan-stag-hw-insert: off [fixed]
>>>> rx-vlan-stag-hw-parse: off [fixed]
>>>> rx-vlan-stag-filter: off [fixed]
>>>> as last on the broken kernels.
>>>>
>>>
>>> I could not reproduce it, I will try it on VM. Meanwhile can you turn
>>> off feature "sg" and try same test ?
>>
>> Hello
>>
>> Your hint was spot-on. With sg off, i can't reproduce the problem and
>> networking seems fine. It works fine either way on 3.9, so this is a
>> regression for 3.10.
>>
> Nice.
> but still this does not look right. Can you tell me driver for the nic?
> `ethtool -i <dev>`

ethtool -i eth0:
driver: hv_netvsc
version: 3.1
firmware-version: N/A
bus-info:
supports-statistics: no
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

>
> Thanks,
> Pravin.