firecracker-microvm/firecracker · error

vsock: invalid queue index: {qidx}

Error message

vsock: invalid queue index: {qidx}

What it means

Error "vsock: invalid queue index: {qidx}" thrown in firecracker-microvm/firecracker.

Source

Thrown at src/vmm/src/devices/virtio/vsock/device.rs:142

    /// Retrieve the cid associated with this vsock device.
    pub fn cid(&self) -> u64 {
        self.cid
    }

    /// Access the backend behind the device.
    pub fn backend(&self) -> &B {
        &self.backend
    }

    /// Signal the guest driver that we've used some virtio buffers that it had previously made
    /// available.
    pub fn signal_used_queue(&self, qidx: usize) -> Result<(), DeviceError> {
        self.device_state
            .active_state()
            .expect("Device is not initialized")
            .interrupt
            .trigger(VirtioInterruptType::Queue(qidx.try_into().unwrap_or_else(
                |_| panic!("vsock: invalid queue index: {qidx}"),
            )))
            .map_err(DeviceError::FailedSignalingIrq)
    }

    /// Signal the guest which queues are ready to be consumed
    pub fn signal_used_queues(&self, used_queues: &[u16]) -> Result<(), DeviceError> {
        self.device_state
            .active_state()
            .expect("Device is not initialized")
            .interrupt
            .trigger_queues(used_queues)
            .map_err(DeviceError::FailedSignalingIrq)
    }

    /// Walk the driver-provided RX queue buffers and attempt to fill them up with any data that we
    /// have pending. Return `true` if the guest needs to be notified (respecting notification
    /// suppression).
    pub fn process_rx(&mut self) -> Result<bool, InvalidAvailIdx> {

View on GitHub (pinned to 81b38b9dad)

Solutions

1. Ensure the vsock queue index is within the number of queues the device exposes.
2. Verify virtio queue negotiation completed before processing queue events.

When it happens

Trigger: Thrown at src/vmm/src/devices/virtio/vsock/device.rs:144 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of firecracker-microvm/firecracker@81b38b9dad (2026-08-19). Data as JSON: /api/errors/3787e22d2f869efc. Report an issue: GitHub.