What were you trying to do that didn't work?

Run qemu-nbd in a kubernetes Pod with port-probing to learn if the service was up. Every port probe (several a minute, to make sure the service is still healthy) results in another line added to the logs about a client not finishing connection.

What is the impact of this issue to you?

Noisy logs detract from correct operation, and port probes are normal enough that they shouldn't trigger server noise.

Please provide the package NVR for which the bug is seen:

How reproducible is this bug?:

100%

Steps to reproduce

1. qemu-nbd -r -f raw path/to/file &
2. nc localhost 10809 </dev/null
3. bash -c 'exec </dev/tcp/localhost/10809'
4. kill $!

Expected results

No messages from qemu-nbd

Actual results

Messages such as:

    qemu-nbd: option negotiation failed: Failed to read flags: Unexpected end-of-file before all data were read
    qemu-nbd: option negotiation failed: Failed to read flags: Unable to read from socket: Connection reset by peer

Upstream patch proposed:

https://lists.gnu.org/archive/html/qemu-devel/2024-11/msg03411.html

but may be too late for qemu 9.2