id = 2125
title = "The value of 'tx_queue_size' is set to only 256 in the network device option on qemu 8.2."
state = "closed"
created_at = "2024-01-26T07:48:51.512Z"
closed_at = "2024-02-05T16:28:01.966Z"
labels = []
url = "https://gitlab.com/qemu-project/qemu/-/issues/2125"
host-os = "Ubuntu 22.04.1 LTS"
host-arch = "x86_64"
qemu-version = "v8.2.0"
guest-os = "whole guest os"
guest-arch = "x86"
description = """I have been using the 'tx_queue_size' value set to 1024 in the network device option on qemu 7.2 without any issues.\\
but when I upgrade to qemu 8.2 I got this error message (and also qemu 8.1) and I cannot use any value other than 256
```
qemu-system-x86_64: -device virtio-net-pci,mq=on,vectors=6,netdev=hostnet_34,id=dpdk_34,mac=F2:20:AF:40:12:65,bus=bridge,addr=0x7,page-per-vq=on,rx_queue_size=1024,tx_queue_size=1024,mrg_rxbuf=on,disable-legacy=on,disable-modern=off,host_mtu=1500,csum=on,guest_csum=on,host_tso4=on,host_tso6=on: Invalid tx_queue_size (= 1024), must be a power of 2 between 256 and 256
```

and I think virtqueue max size value has never changed from 1024.\\
https://gitlab.com/qemu-project/qemu/-/blob/staging-8.2/include/hw/virtio/virtio.h?ref_type=heads#L62"""
reproduce = """1. boot qemu-system-x86_64 on qemu 8.2 and network device option set tx_queue_size value over 256"""
additional = """- I'm using hardware vDPA offloading with mellanox NIC card."""