mixed VLAN problems on msk(4)

[Ian Freislich]

Hi

Debugging some network problems last night, I noticed that I'd get
packet loss on a mixed tagged/untagged network every time a tagged
VLAN packet arrived, so long as hardware VLAN support was enabled
on my NIC.  The moment hardware tagging was disabled (manually, or
by tcpdump) the packet loss disappeared.

My msk(4) hardware:

mskc0 at pci0:2:0:0:       class=0x020000 card=0x532111ab chip=0x436211ab rev=0x22 hdr=0x00
    vendor     = 'Marvell Semiconductor (Was: Galileo Technology Ltd)'
    device     = 'Marvell Yukon 88E8053 PCI-E Gigabit Ethernet Controller (88E8053)'
    class      = network
    subclass   = ethernet
    cap 01[48] = powerspec 2  supports D0 D1 D2 D3  current D0
    cap 03[50] = VPD
    cap 05[5c] = MSI supports 2 messages, 64 bit enabled with 2 messages
    cap 10[e0] = PCI-Express 1 legacy endpoint max data 128(128) link x1(x1)

The switch was configured as follows:

Port is member in: 
 
Vlan               Name               Egress rule Port Membership Type 
---- -------------------------------- ----------- -------------------- 
 14                 14                 Untagged          Static        
 26                 26                  Tagged           Static        
1000               1000                 Tagged           Static        

It appears not to matter whether the vlans are configured with the
msk(4) interface as the parent or not.  For example, whenever one
of these broadcasts is recieved:

12:49:36.093250 IP 41.154.87.2 > 224.0.0.18: VRRPv2, Advertisement, vrid 19, prio 0, authtype none, intvl 1s, length 36
12:49:37.097514 IP 41.154.87.2 > 224.0.0.18: VRRPv2, Advertisement, vrid 19, prio 0, authtype none, intvl 1s, length 36
12:49:38.099525 IP 41.154.87.2 > 224.0.0.18: VRRPv2, Advertisement, vrid 19, prio 0, authtype none, intvl 1s, length 36

traffic to the untagged address on vlan14 (basically the address
on msk0) is dropped.  If I disable vlanhwtag on msk0, the interface
suffers no packet loss on reciept of tagged frames.

Ian

--
Ian Freislich