msk driver issues [was: Re: vlan issues with 7.0-RC3]

[Pyun YongHyeon]

On Sun, Mar 02, 2008 at 07:57:28PM -0800, Christopher Cowart wrote:
 > On Fri, Feb 29, 2008 at 03:03:53PM +0900, Pyun YongHyeon wrote:
 > > On Wed, Feb 27, 2008 at 06:38:40PM -0800, Christopher Cowart wrote:
 > >>On Tue, Feb 26, 2008 at 04:43:55PM +0900, Pyun YongHyeon wrote:
 > >>>On Mon, Feb 25, 2008 at 01:17:12AM -0800, Christopher Cowart wrote:
 > >>>> I have a mac mini running 7.0-RC3, which I'm trying to turn it into a
 > >>>> router. I have a Linksys SRW2008 "fully managed" (via an IE only web
 > >>>> interface, ick) switch. 
 > >>>> 
 > >>>> Switch:
 > >>>>   Port 1 - Trunk vlans 10,60,98 - FreeBSD Box
 > >>>>   Port 7 - Access vlan 98 - Existing LAN (192.168.1.0/24)
 > >>>> 
 > >>>> OpenWRT (192.168.1.1):
 > >>>>   WRT54G box on the Existing LAN
 > >>>> 
 > >>>> FreeBSD Box:
 > >>>>   ifconfig msk0 up
 > >>>>   ifconfig vlan98 create vlan 98 vlandev msk0 inet 192.168.1.67/24
 > >>>> 
 > >>>> With this configuration, I can ping hosts on the other lan segment (Port
 > >>>> 7). Arp and icmp seem to be quite happy. Unfortunately, I'm not having
 > >>>> any luck with tcp and udp. Any attempt to ssh to OpenWRT or dig
 > >>>> @OpenWRT hangs indefinitely. If I do a tcpdump, I see the SYN or A?
 > >>>> leaving and absolutely no response returning. If I run a tcpdump on
 > >>>> OpenWRT, I see no incoming traffic.
 > >>>> 
 > >>>> When I try to connect *to* the FreeBSD box from the other lan segment, I
 > >>>> continue to have problems. tcpdump shows the SYNs arriving via vlan98
 > >>>> and the FreeBSD box responding with SYN-ACK. OpenWRT receives the SYNACK.
 > >>>> 
 > >>>> I disabled ipfw just to be sure (sysctl -w net.inet.ip.fw.enable=0), but
 > >>>> it had no effect on the problem. If I connect the FreeBSD box to a vlan
 > >>>> 98 access port and assign the address to msk0, my connectivity problems
 > >>>> go away. This leads me to believe that the firewall on OpenWRT is not
 > >>>> the problem and the problem is related to vlans.
 > >>>> 
 > >>>> Thinking it was a problem with the not-so-cheap Linksys POS (bitterness
 > >>>> about the IE web interface again), I plugged my MacBook (running
 > >>>> Leopard, not FreeBSD) into the trunk port. Running the ifconfig commands
 > >>>> above (s/msk0/en0/), I got up and running without any problems. This
 > >>>> causes me to suspect the FreeBSD box.
 > >>>> 
 > >>>> Does anyone have any idea what's going on here? Any suggestions for
 > >>>> further troubleshooting?
 > >>>
 > >>> Try disabling hardware features one by one in msk(4) and see how
 > >>> it goes.
 > >>>  o Disable TSO.
 > >>>  o Disable Tx checksum offload.
 > >>>  o Disable VLAN hardware tagging.
 > >>
 > >>Works great after `sudo ifconfig msk0 -txcsum'. 
 > >>
 > >>Is this a known bug, or should I file a PR? Let me know if there are any
 > >>other details I can provide to help somebody squash it.
 > > 
 > > Would you capture broken TCP/UDP frames with tcpdump on receiving side
 > > and show it to me?
 > 
 > Thanks for your help. I will e-mail you the corresponding tracefile
 > off-list. I wanted to discuss my initial findings here.
 > 
 > When the FreeBSD box sends tcp or udp traffic to elsewhere on the
 > network, it is not seen at the receiving side, not even with bad
 > checksums. I tried setting up the Linksys device with a port mirror, but
 > apparently that's only supported on native vlan access ports. Great.
 > 
 > So, I decided to cross-connect the FreeBSD box with my MacBook. I set up
 > a vlan interface and was able to reproduce the behavior. I did a traffic
 > dump on the parent interface (not the vlan interface) on the MacBook,
 > and noticed that the ethernet frames originating from the FreeBSD box
 > lacked 802.1q tags. Is it possible that the interface is not performing
 > the hardware tagging when txcsum is enabled? 
 > 

Fix committed to HEAD, if_msk.c rev 1.30.

 > While I have your attention, I am also suffering from a problem that was
 > reported to -questions here[1]. About 3 times a day, I'll see the
 > watchdog timeout (missed Tx interrupts) message get logged, after which
 > point the NIC is useless until I reboot. Any ideas?
 > 
 > [1] http://lists.freebsd.org/pipermail/freebsd-questions/2008-February/169633.html
 > 

I'll have a look.

-- 
Regards,
Pyun YongHyeon