Date: Thu, 30 Nov 2006 18:47:21 +0000 (GMT) From: wpaul@FreeBSD.ORG (Bill Paul) To: wpaul@FreeBSD.ORG (Bill Paul) Cc: pyunyh@gmail.com, stable@freebsd.org, ed@fxq.nl, net@freebsd.org Subject: Re: re(4) needs promisc to work properly Message-ID: <20061130184721.F14E716A407@hub.freebsd.org> In-Reply-To: <20061129232331.8E55016A415@hub.freebsd.org> from Bill Paul at "Nov 29, 2006 11:23:31 pm"
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> > On Tue, Nov 28, 2006 at 08:46:00PM +0100, Ed Schouten wrote:
> > > Hello,
> > >
> > > I'm running FreeBSD 6.2-PRERELEASE on my new desktop. It has the
> > > following hardware:
> > >
> > > - Intel Core 2 Duo 6400
> > > - Asus P5B motherboard
> > > - On-board Realtek NIC (8168B/8111B)
> > >
> > > For some reason, it drops all incoming IPv6 packets. I can only SSH to
> > > the machine using IPv6 when I run the following command:
> > >
> > > $ ifconfig re0 promisc
> > >
> > > Is this a known issue about these NICs?
> >
> > No, I'm not aware of the issue.
> >
> > The issue can happen on a NIC with incorrectly programmed ethernet
> > address. Would you show me dmesg/tcpdump output of your system?
> > Make sure to add -e option to tcpdump(1).
>
> It's more likely a problem with the multicast filter programming.
> IPv6 is all about the multicasting (neighbord discovery depends on it
> to work correctly). I can't explain why it's not working though.
> I've tested the sample 8168B/8111B cards that RealTek sent me, and I
> didn't have any multicast problems with them.
>
> -Bill
I guess I wasn't diligent enough in my testing. Upon closer inspection
of the documentation, it appears RealTek abitrarily decided to
reverse the order of the multicast hash registers in the PCIe parts:
you have to write the hash table out in reverse order.
I have no idea why they did this. In any case, I'm attaching a patch
which should fix the problem.
-Bill
--ELM826140722-92783-0_
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*** if_re.c.orig Thu Nov 30 10:37:42 2006
--- if_re.c Thu Nov 30 10:37:05 2006
***************
*** 620,625 ****
--- 620,626 ----
struct ifmultiaddr *ifma;
u_int32_t rxfilt;
int mcnt = 0;
+ u_int32_t hwrev;
RL_LOCK_ASSERT(sc);
***************
*** 660,667 ****
rxfilt &= ~RL_RXCFG_RX_MULTI;
CSR_WRITE_4(sc, RL_RXCFG, rxfilt);
! CSR_WRITE_4(sc, RL_MAR0, hashes[0]);
! CSR_WRITE_4(sc, RL_MAR4, hashes[1]);
}
static void
--- 661,684 ----
rxfilt &= ~RL_RXCFG_RX_MULTI;
CSR_WRITE_4(sc, RL_RXCFG, rxfilt);
!
! /*
! * For some unfathomable reason, RealTek decided to reverse
! * the order of the multicast hash registers in the PCI Express
! * parts. This means we have to write the hash pattern in reverse
! * order for those devices.
! */
!
! hwrev = CSR_READ_4(sc, RL_TXCFG) & RL_TXCFG_HWREV;
!
! if (hwrev == RL_HWREV_8100E || hwrev == RL_HWREV_8101E ||
! hwrev == RL_HWREV_8168_SPIN1 || hwrev == RL_HWREV_8168_SPIN2) {
! CSR_WRITE_4(sc, RL_MAR0, bswap32(hashes[1]));
! CSR_WRITE_4(sc, RL_MAR4, bswap32(hashes[0]));
! } else {
! CSR_WRITE_4(sc, RL_MAR0, hashes[0]);
! CSR_WRITE_4(sc, RL_MAR4, hashes[1]);
! }
}
static void
--ELM826140722-92783-0_--
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