lots of bad checksum on igb

[k simon]

Hi,List,

  I have tested haproxy on dfly 3.6.2 and found a lot of bad checksum
unless "ifconfig igb0 -txcsum -rxcsum -tso".

Simon


P.S.
igb0 at pci0:1:0:0:	class=0x020000 card=0xa04c8086 chip=0x10c98086 rev=0x01
hdr=0x00
    vendor     = 'Intel Corporation'
    device     = '82576 Gigabit Network Connection'
    class      = network
    subclass   = ethernet
igb1 at pci0:1:0:1:	class=0x020000 card=0xa04c8086 chip=0x10c98086 rev=0x01
hdr=0x00
    vendor     = 'Intel Corporation'
    device     = '82576 Gigabit Network Connection'
    class      = network
    subclass   = ethernet

# ifconfig igb1
igb1: flags=8843<UP,BROADCAST,RUNNING,SIMPLEX,MULTICAST> mtu 1500
	options=5b<RXCSUM,TXCSUM,VLAN_MTU,VLAN_HWTAGGING,RSS>
	inet6 fe80::21b:21ff:fea8:f6b5%igb1 prefixlen 64 scopeid 0x2
	inet 192.168.130.17 netmask 0xfffffe00 broadcast 192.168.131.255
	ether 00:1b:21:a8:f6:b5
	media: Ethernet 1000baseT <full-duplex>
	status: active


# tcpdump -vv -n -i igb1
tcpdump: listening on igb1, link-type EN10MB (Ethernet), capture size
65535 bytes
00:55:45.864386 IP (tos 0x0, ttl 64, id 24083, offset 0, flags [DF],
proto TCP (6), length 670)
    192.168.130.50.3002 > 192.168.130.17.15231: Flags [P.], cksum 0x9e22
(correct), seq 2769251432:2769252062, ack 3651462828, win 33580, length 630
00:55:45.864403 IP (tos 0x0, ttl 64, id 30506, offset 0, flags [DF],
proto TCP (6), length 40, bad cksum 0 (->3e11)!)
    192.168.130.17.15231 > 192.168.130.50.3002: Flags [.], cksum 0xcccc
(correct), seq 1, ack 630, win 16890, length 0
00:55:45.864435 IP (tos 0x0, ttl 64, id 59651, offset 0, flags [DF],
proto TCP (6), length 40, bad cksum 0 (->cc37)!)
    192.168.130.17.15231 > 192.168.130.50.3002: Flags [F.], cksum 0xcccb
(correct), seq 1, ack 630, win 16890, length 0
00:55:45.864449 IP (tos 0x0, ttl 64, id 29524, offset 0, flags [DF],
proto TCP (6), length 40, bad cksum 0 (->41e7)!)
    192.168.130.17.15231 > 192.168.130.50.3002: Flags [R.], cksum 0xccc7
(correct), seq 2, ack 630, win 16890, length 0
00:55:45.864626 IP (tos 0x0, ttl 64, id 24105, offset 0, flags [DF],
proto TCP (6), length 40)
    192.168.130.50.3002 > 192.168.130.17.15231: Flags [.], cksum 0x8b99
(correct), seq 630, ack 2, win 33580, length 0
00:55:45.864635 IP (tos 0x0, ttl 64, id 17387, offset 0, flags [DF],
proto TCP (6), length 40, bad cksum 0 (->7150)!)
    192.168.130.17.15231 > 192.168.130.50.3002: Flags [R], cksum 0x22c0
(correct), seq 3651462829, win 0, length 0
00:55:46.176994 IP (tos 0x0, ttl 64, id 8022, offset 0, flags [DF],
proto TCP (6), length 48, bad cksum 0 (->95ef)!)
    192.168.130.17.15232 > 192.168.130.32.3003: Flags [S], cksum 0x75b2
(correct), seq 3024833635, win 16384, options [mss 1460,nop,nop,sackOK],
length 0
00:55:46.177062 IP (tos 0x0, ttl 64, id 6400, offset 0, flags [DF],
proto TCP (6), length 44)
    192.168.130.32.3003 > 192.168.130.17.15232: Flags [S.], cksum 0x069f
(correct), seq 2868943112, ack 3024833636, win 32768, options [mss
1460], length 0
00:55:46.177074 IP (tos 0x0, ttl 64, id 45321, offset 0, flags [DF],
proto TCP (6), length 40, bad cksum 0 (->444)!)
    192.168.130.17.15232 > 192.168.130.32.3003: Flags [.], cksum 0x59ec
(correct), seq 1, ack 1, win 17520, length 0
00:55:46.177101 IP (tos 0x0, ttl 64, id 21368, offset 0, flags [DF],
proto TCP (6), length 80, bad cksum 0 (->61ad)!)