Re: wake-on-lan lost from rpi4 (works on rpi3)

From: Ronald Klop <ronald-lists_at_klop.ws>
Date: Sat, 29 Oct 2022 05:16:46 UTC
Van: Ronald Klop <ronald-lists@klop.ws>
Datum: 25 oktober 2022 20:32
Aan: mike@karels.net
CC: freebsd-arm@freebsd.org
Onderwerp: Re: wake-on-lan lost from rpi4 (works on rpi3)

> 
> 
> 
>  
> Van: Mike Karels 
> Datum: dinsdag, 25 oktober 2022 18:11
> Aan: Ronald Klop 
> CC: freebsd-arm@freebsd.org
> Onderwerp: Re: wake-on-lan lost from rpi4 (works on rpi3)
>> 
>> I wrote:
>> > On 25 Oct 2022, at 9:13, Ronald Klop wrote:
>> 
>> > > Van: Mike Karels 
>> > > Datum: dinsdag, 25 oktober 2022 14:55
>> > > Aan: Ronald Klop 
>> > > CC: freebsd-arm@freebsd.org
>> > > Onderwerp: Re: wake-on-lan lost from rpi4 (works on rpi3)
>> > >>
>> > >> On 25 Oct 2022, at 6:57, Ronald Klop wrote:
>> > >>
>> > >>> Hi,
>> > >>>
>> > >>> When I do "wake ue0 `cat /home/ronald/freenas.ethernet `" on my RPI3B+ my NAS boots and tcpdump shows the following line on my rpi3 as well as on my router.
>> > >>> 13:39:44.344111 IPX 00217046.6c:da:00:21:70:46.6cda > 00217046.6c:da:00:21:70:46.6cda: ipx-#6cda 65505
>> > >>>
>> > >>> When I do "wake genet0 `cat /home/ronald/freenas.ethernet `" on my RPI4 my NAS does not boot and tcpdump only show this on my rpi4 and *not* on my router.
>> > >>> 13:37:26.448251 IPX 00217046.6c:da:00:21:70:46.6cda > 00217046.6c:da:00:21:70:46.6cda: ipx-#6cda 65505
>> > >>>
>> > >>> Firewall ipfw does not indicate that it blocks anything.
>> > >>>
>> > >>> RPI4 runs:
>> > >>> FreeBSD rpi4 14.0-CURRENT FreeBSD 14.0-CURRENT #11 main-4f0c9b76cf: Sat Aug 13 23:59:19 CEST 2022     ronald@rpi4:/home/ronald/dev/obj/home/ronald/dev/freebsd/arm64.aarch64/sys/GENERIC-NODEBUG arm64
>> > >>>
>> > >>> genet0: flags=8943 metric 0 mtu 1500
>> > >>>    options=68000b
>> > >>>
>> > >>>
>> > >>> RPI3 runs:
>> > >>> FreeBSD rpi3 13.1-RELEASE-p2 FreeBSD 13.1-RELEASE-p2 GENERIC arm64
>> > >>>
>> > >>> ue0: flags=8943 metric 0 mtu 1500
>> > >>>    options=80009
>> > >>>
>> > >>>
>> > >>> Does genet0 not support these packages?
>> > >>> What can prevent this packet to go on the ethernet while tcpdump still shows it is outgoing on the interface?
>> > >>> genet0 does have a vlan configured connected to a bridge0 for some jails
>> > >>> vlan3: flags=8943 metric 0 mtu 1500
>> > >>>    options=80000
>> > >>>    groups: vlan
>> > >>>    vlan: 3 vlanproto: 802.1q vlanpcp: 0 parent interface: genet0
>> > >>>
>> > >>> ue0 is itself connected to a bridge0
>> > >>
>> > >> Is the RPI3 also on a vlan and bridge?
>> > >>
>> > >> Is the router (or switch) expecting the packet on the vlan?
>> > >> If so, maybe you need to send on vlan3 rather than genet0.
>> > >>
>> > >> The genet interface has some oddities about packet layouts;
>> > >> that could be hitting here.  You could try disabling TCP TX
>> > >> checksum offload: ifconfig genet0 -txcsum -txcsum6; that
>> > >> simplifies some of the issues.
>> > >>
>> > >>         Mike
>> > >>
>> > >>> Regards,
>> > >>> Ronald.
>> > >
>> > >
>> > > Hi,
>> > >
>> > > Thanks for the hint. I experimented some further.
>> > >
>> > > Disabling -txcsum -rxcsum didn't matter.
>> 
>> > -rxcsum doesn't matter, but you need to do -txcsum6 as well as
>> > -txcsum.  (See the code that calls gen_parse_tx.)
>> 
>> > > But when I use bridge0 or vlan3 as device then it goes into the wire but on the VLAN which is not where my NAS is which I want to boot.
>> > >
>> > > Looking at the driver I found this interesting peace of code.
>> > >
>> > > static int
>> > > gen_parse_tx(struct mbuf *m, int csum_flags) {
>> > > ...
>> > >        if (ether_type == ETHERTYPE_IP) {
>> > >                COPY(((struct ip *)p)->ip_hl << 2);
>> > >                offset += ((struct ip *)p)->ip_hl << 2;
>> > >        } else if (ether_type == ETHERTYPE_IPV6) {
>> > >                COPY(sizeof(struct ip6_hdr));
>> > >                offset += sizeof(struct ip6_hdr);
>> > >        } else {
>> > >                /*
>> > >                 * Unknown whether other cases require moving a header;
>> > >                 * ARP works without.
>> > >                 */
>> > >        }
>> > > ...
>> > > }
>> > >
>> > > There is also some code which handles EHTERTYPE_VLAN.
>> > >
>> > > I don't have time to start debugging this today. But would this ring a bell to anybody in connection to a wake-on-lan packet?
>> 
>> > I ran some experiments with tx checksum disabled, and it seems to
>> > matter.  I have a change for the last block you listed that might
>> > help, but I haven't tested it yet.
>> 
>> This patch seems to work:
>> 
>> diff --git a/sys/arm64/broadcom/genet/if_genet.c b/sys/arm64/broadcom/genet/if_genet.c
>> index 327af8acbcdd..b7ab86e7931d 100644
>> --- a/sys/arm64/broadcom/genet/if_genet.c
>> +++ b/sys/arm64/broadcom/genet/if_genet.c
>> @@ -1305,6 +1305,8 @@ gen_parse_tx(struct mbuf *m, int csum_flags)
>>          * Unknown whether other cases require moving a header;
>>          * ARP works without.
>>          */
>> +       COPY(min(gen_tx_hdr_min, m->m_len));
>> +       offset += min(gen_tx_hdr_min, m->m_len);
>>     }
>>     return (offset);
>>  #undef COPY
>> 
>> It needs an updated comment, but should be testable.
>> 
>>         Mike
>> 
>> > > Regards,
>> > > Ronald.
>> 
>>  
> 
> Hi,
> 
> Thanks. Disabling both -txcsum and -txcsum6 works for me also.
> I can test your patch tommorow or on Thursday. I'm first testing a big mongodb 6.0 patch I hope to commit soon and this build occupies my rpi4 for some more hours.
> 
> Regards,
> Ronald.
>  


Hi,

Your patch works for me. I can send wake-on-lan packets now. Should I test other specific things also?

Regards,

Ronald.