Virtual Machine Hotplug via VMM Queue and Interrupt

Solution Overview

Problem

The conventional device hotplug mode using ACPI and PCI mechanisms in secure containers for platform as a service (PaaS) slows down virtual machine startup and increases security risks.

Innovation Solution

A device hotplug method that uses a virtual machine monitor (VMM) to determine operation resource information, stores it in an operation queue, and sends an interrupt trigger signal to the sub-operating system, allowing for hotplug operations without relying on ACPI and PCI mechanisms.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If ACPI and PCI mechanisms are used for device hotplug in secure containers, then device hotplug functionality is achieved, but virtual machine startup speed decreases and security risks increase

Engineering Contradiction:

ImprovesecurityVSAvoidcode complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent extracts the essential hotplug functionality from the complex ACPI and PCI mechanisms, implementing a simplified custom hotplug device that only handles the specific hotplug operations needed. This removes unnecessary complexity while maintaining the core functionality, thereby improving security by reducing the attack surface and speeding up startup by loading fewer components.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent implements a dedicated hotplug device with specialized functionality tailored specifically for secure container hotplug operations, rather than using general-purpose ACPI/PCI mechanisms. This localized solution optimizes performance and security for the specific use case by implementing only the necessary protocols and data structures.

Inventive Principle:

Principle #3Local quality

2Speed

If ACPI and PCI mechanisms are used for device hotplug, then device hotplug functionality is achieved, but virtual machine startup speed decreases

Engineering Contradiction:

Improvestartup speedVSAvoidmechanism complexity

Core Design Contradiction:

SpeedVSDevice complexity

Solution Approach 1:

The patent extracts the essential hotplug functionality from the complex ACPI and PCI mechanisms, implementing a simplified custom hotplug device that only handles the specific hotplug operations needed. This removes unnecessary complexity while maintaining the core functionality, thereby improving security by reducing the attack surface and speeding up startup by loading fewer components.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

Instead of adapting the hotplug functionality to work within the existing ACPI and PCI frameworks, the patent inverts the approach by creating a standalone custom hotplug device that operates independently. This reversal allows optimization for speed without being constrained by the overhead and complexity of the traditional mechanisms.

Inventive Principle:

Principle #13The other way round (Inversion)

3Ease of operation

If ACPI and PCI mechanisms are used for device hotplug, then device hotplug functionality is achieved, but security risks increase

Engineering Contradiction:

Improvehotplug operationVSAvoidsecurity risks

Core Design Contradiction:

Ease of operationVSObject-affected harmful factors

Solution Approach 1:

The patent extracts the essential hotplug functionality from the complex ACPI and PCI mechanisms, implementing a simplified custom hotplug device that only handles the specific hotplug operations needed. This removes unnecessary complexity while maintaining the core functionality, thereby improving security by reducing the attack surface and speeding up startup by loading fewer components.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent introduces a custom hotplug device as an intermediary layer between the virtual machine monitor and the sub-operating system. This intermediary handles all hotplug operations through a controlled interface (operation queue and interrupt trigger signal), providing a security boundary that prevents direct access to underlying system components and reduces exposure to security risks.

Inventive Principle:

Principle #24Intermediary (Mediator)

Data Source

PatentUS20250068721A1Device hotplug method, computer device, and storage medium

Publication Date: 2025.02.27 BEIJING VOLCANO ENGINE TECH CO LTD

AI summary

Provided are a device hot-plug method, a computer device, and a storage medium. The method includes: in response to a hotplug request received by a virtual machine monitor for a virtual target device in a virtual machine, determining operation resource information corresponding to the hotplug request using the virtual machine monitor, where the operation resource information includes resource information needed for performing hotplug on the virtual target device; storing the operation resource information to an operation queue of a preset hotplug device, and sending an interrupt trigger signal to a sub-operating system of the virtual machine; and acquiring the operation resource information from the operation queue by using the sub-operating system when the interrupt trigger signal is detected by the sub-operating system, and executing a hotplug operation for the virtual target device according to the operation resource information.