https://bugzilla.kernel.org/show_bug.cgi?id=219161 Bug ID: 219161 Summary: VM with virtio-net doesn't receive large UDP packets (e.g 65507 bytes) from host Product: Virtualization Version: unspecified Hardware: All OS: Linux Status: NEW Severity: normal Priority: P3 Component: kvm Assignee: virtualization_kvm@xxxxxxxxxxxxxxxxxxxx Reporter: wquan@xxxxxxxxxx Regression: No Description： Large UDP packets (e.g 65507 bytes) are not received in VM using virtio-net when sent from host to VM, while smaller packets are received successfully. The issue occurs with or without vhost enabled, and can be reproduce with 6.5.0-rc5+ Build Date & Hardware: 6.11.0-rc2+ (d4560686726f7a357922f300fc81f5964be8df04 Merge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost) Steps to Reproduce: 1. boot a vm from kvm -device '{"id": "pcie-root-port-3", "port": 3, "driver": "pcie-root-port", "addr": "0x1.0x3", "bus": "pcie.0", "chassis": 4}' \ -device '{"driver": "virtio-net-pci", "mac": "9a:59:9c:26:c7:52", "id": "id1GUehY", "netdev": "idIlyxUy", "bus": "pcie-root-port-3", "addr": "0x0"}' \ -netdev '{"id": "idIlyxUy", "type": "tap", "vhost": true}' \ 2. on vm, disable iptables and nftables. then run "netserver" 3. on host # netperf -H 192.168.58.21 -t UDP_STREAM -- -m 65507 MIGRATED UDP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.58.21 () port 0 AF_INET : interval : demo Socket Message Elapsed Messages Size Size Time Okay Errors Throughput bytes bytes secs # # 10^6bits/sec 212992 65507 10.00 385575 0 20206.13 212992 10.00 86 4.51 # netperf -H 192.168.58.21 -t UDP_STREAM -- -m 2800 MIGRATED UDP STREAM TEST from 0.0.0.0 (0.0.0.0) port 0 AF_INET to 192.168.58.21 () port 0 AF_INET : interval : demo Socket Message Elapsed Messages Size Size Time Okay Errors Throughput bytes bytes secs # # 10^6bits/sec 212992 2800 10.00 5125735 0 11481.60 212992 10.00 3562544 7980.07 -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
