re(4) checksum offload problem

[Jelte Jansen]

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Hi,

i'm seeing bad IP/UDP checksums on packets on a realtek gigabit network
card. Turning offloading off (ifconfig -txcsum) seems to make the
problem disappear.

Attached are pcap files showing the bad checksums; the IP header is set
to 0x0000 and then TCP/UDP headers are wrong too. The machine in
question is on .99. These were taken on the host itself but i also see
them on the other machine.

pciconf:
re0 at pci0:1:8:0: class=0x020000 card=0xee221113 chip=0x816910ec rev=0x10
hdr=0x00
    vendor     = 'Realtek Semiconductor'
    device     = 'RTL8110SB Single-Chip Gigabit LOM Ethernet Controller'
    class      = network
    subclass   = ethernet

Version:
$FreeBSD: src/sys/dev/re/if_re.c,v 1.95 2007/08/14 02:00:04 yongari E\
xp $

Jelte
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