I have several virtual machines running OpenSUSE Leap 15.6 in a Nutanix AHV
environment. Since upgrading the kernel in several of these from
6.4.0-150600.23.17-default to 6.4.0-150600.23.22-default I am seeing a severe
impact on network performance and reliability - slow transfer speeds and
disconnections.

This issue has been accompanied by these entries in /var/log/messages:

2024-10-04T10:22:08.639264+01:00 testserver1 kernel: message repeated 3 times:
[[    C2] eth1: bad gso: type: 1, size: 1448]
2024-10-04T10:22:08.639265+01:00 testserver1 kernel: [    C2] eth1: bad gso:
type: 1, size: 1388
2024-10-04T10:22:08.642595+01:00 testserver1 kernel: [    C2] eth1: bad gso:
type: 1, size: 1448
2024-10-04T10:22:08.642602+01:00 testserver1 kernel: [    C2] eth1: bad gso:
type: 1, size: 1448

Reverting to 6.4.0-150600.23.17 resolves the issue.

NIC details:

# ethtool -i eth1
driver: virtio_net
version: 1.0.0
firmware-version: 
expansion-rom-version: 
bus-info: 0000:00:03.0
supports-statistics: yes
supports-test: no
supports-eeprom-access: no
supports-register-dump: no
supports-priv-flags: no

# lspci -nn | grep Ethernet
00:03.0 Ethernet controller [0200]: Red Hat, Inc. Virtio network device
[1af4:1000]

Comparison of wget download speed of a 97MB file between the kernel versions
(file is served via HTTP from another virtual machine in the same physical
location):

# uname -a
Linux testserver1 6.4.0-150600.23.17-default #1 SMP PREEMPT_DYNAMIC Tue Jul 30
06:37:32 UTC 2024 (9c450d7) x86_64 x86_64 x86_64 GNU/Linux

...
2024-10-04 14:59:05 (262 MB/s) - ‘tmp.dat’ saved [101473111/101473111]

# uname -a
Linux testserver1 6.4.0-150600.23.22-default #1 SMP PREEMPT_DYNAMIC Fri Sep 13
10:42:50 UTC 2024 (5c05eeb) x86_64 x86_64 x86_64 GNU/Linux

...
2024-10-04 15:08:18 (899 KB/s) - ‘tmp.dat’ saved [101473111/101473111]