virtio-net regression for aarch64 guests

Host environment

Operating system: Pop! OS 22.04 LTS
OS/kernel version: Linux 6.9.3
Architecture: x86
QEMU flavor: qemu-system-aarch64
QEMU version: 9.2
QEMU command line: qemu-system-aarch64 -kernel kernel-6.12.7 -append "root=/dev/vda1 console=ttyAMA0 ro" -machine type=virt -cpu cortex-a76 -smp cpus=4 -m size=30720 -drive file=lbl.qcow2,index=0,media=disk -netdev tap,id=net0,ifname=tap0,script=no,downscript=no -device virtio-net-device,netdev=net0,mac=aa:bb:cc:dd:ee:01 -nographic

Emulated/Virtualized environment

Operating system: Custom Linux
OS/kernel version: 6.12.7
Architecture: aarch64

Description of problem

The host system is running DHCP via dnsmasq 2.88. QEMU 9.1 works properly and completes DHCP handshake. QEMU 9.2 fails the DHCP handshake after DHCPOFFER with "eth0: checksum failure from 10.2.83.1".

I found by bisecting that the issue was introduced by commit 7987d2be "virtio-net: Copy received header to buffer". Reverting that commit on 9.2.0 corrects the issue.

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