[PATCH v12 02/24] docs: geniezone: Introduce GenieZone hypervisor

From: Liju-clr Chen
Date: Tue Jul 30 2024 - 04:31:42 EST


From: Yingshiuan Pan <yingshiuan.pan@xxxxxxxxxxxx>

GenieZone is MediaTek proprietary hypervisor solution, and it is running
in EL2 stand alone as a type-I hypervisor. It is a pure EL2
implementation which implies it does not rely any specific host VM, and
this behavior improves GenieZone's security as it limits its interface.

Signed-off-by: Yingshiuan Pan <yingshiuan.pan@xxxxxxxxxxxx>
Co-developed-by: Yi-De Wu <yi-de.wu@xxxxxxxxxxxx>
Signed-off-by: Yi-De Wu <yi-de.wu@xxxxxxxxxxxx>
Signed-off-by: Liju Chen <liju-clr.chen@xxxxxxxxxxxx>
---
Documentation/virt/geniezone/introduction.rst | 87 +++++++++++++++++++
Documentation/virt/index.rst | 1 +
MAINTAINERS | 6 ++
3 files changed, 94 insertions(+)
create mode 100644 Documentation/virt/geniezone/introduction.rst

diff --git a/Documentation/virt/geniezone/introduction.rst b/Documentation/virt/geniezone/introduction.rst
new file mode 100644
index 000000000000..f280476228b3
--- /dev/null
+++ b/Documentation/virt/geniezone/introduction.rst
@@ -0,0 +1,87 @@
+.. SPDX-License-Identifier: GPL-2.0
+
+======================
+GenieZone Introduction
+======================
+
+Overview
+========
+GenieZone hypervisor (gzvm) is a type-1 hypervisor that supports various virtual
+machine types and provides security features such as TEE-like scenarios and
+secure boot. It can create guest VMs for security use cases and has
+virtualization capabilities for both platform and interrupt. Although the
+hypervisor can be booted independently, it requires the assistance of GenieZone
+hypervisor kernel driver(also named gzvm) to leverage the ability of Linux
+kernel for vCPU scheduling, memory management, inter-VM communication and virtio
+backend support.
+
+Supported Architecture
+======================
+GenieZone now only supports MediaTek ARM64 SoC.
+
+Features
+========
+
+- vCPU Management
+
+ VM manager aims to provide vCPUs on the basis of time sharing on physical
+ CPUs. It requires Linux kernel in host VM for vCPU scheduling and VM power
+ management.
+
+- Memory Management
+
+ Direct use of physical memory from VMs is forbidden and designed to be
+ dictated to the privilege models managed by GenieZone hypervisor for security
+ reason. With the help of gzvm module, the hypervisor would be able to manipulate
+ memory as objects.
+
+- Virtual Platform
+
+ We manage to emulate a virtual mobile platform for guest OS running on guest
+ VM. The platform supports various architecture-defined devices, such as
+ virtual arch timer, GIC, MMIO, PSCI, and exception watching...etc.
+
+- Inter-VM Communication
+
+ Communication among guest VMs was provided mainly on RPC. More communication
+ mechanisms were to be provided in the future based on VirtIO-vsock.
+
+- Device Virtualization
+
+ The solution is provided using the well-known VirtIO. The gzvm module would
+ redirect MMIO traps back to VMM where the virtual devices are mostly emulated.
+ Ioeventfd is implemented using eventfd for signaling host VM that some IO
+ events in guest VMs need to be processed.
+
+- Interrupt virtualization
+
+ All Interrupts during some guest VMs running would be handled by GenieZone
+ hypervisor with the help of gzvm module, both virtual and physical ones.
+ In case there's no guest VM running out there, physical interrupts would be
+ handled by host VM directly for performance reason. Irqfd is also implemented
+ using eventfd for accepting vIRQ requests in gzvm module.
+
+Platform architecture component
+===============================
+
+- vm
+
+ The vm component is responsible for setting up the capability and memory
+ management for the protected VMs. The capability is mainly about the lifecycle
+ control and boot context initialization. And the memory management is highly
+ integrated with ARM 2-stage translation tables to convert VA to IPA to PA
+ under proper security measures required by protected VMs.
+
+- vcpu
+
+ The vcpu component is the core of virtualizing aarch64 physical CPU runnable,
+ and it controls the vCPU lifecycle including creating, running and destroying.
+ With self-defined exit handler, the vm component would be able to act
+ accordingly before terminated.
+
+- vgic
+
+ The vgic component exposes control interfaces to Linux kernel via irqchip, and
+ we intend to support all SPI, PPI, and SGI. When it comes to virtual
+ interrupts, the GenieZone hypervisor would write to list registers and trigger
+ vIRQ injection in guest VMs via GIC.
diff --git a/Documentation/virt/index.rst b/Documentation/virt/index.rst
index 7fb55ae08598..cf12444db336 100644
--- a/Documentation/virt/index.rst
+++ b/Documentation/virt/index.rst
@@ -16,6 +16,7 @@ Virtualization Support
coco/sev-guest
coco/tdx-guest
hyperv/index
+ geniezone/introduction

.. only:: html and subproject

diff --git a/MAINTAINERS b/MAINTAINERS
index 12b870712da4..a61f74e258f8 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -9446,6 +9446,12 @@ F: include/vdso/
F: kernel/time/vsyscall.c
F: lib/vdso/

+GENIEZONE HYPERVISOR DRIVER
+M: Yingshiuan Pan <yingshiuan.pan@xxxxxxxxxxxx>
+M: Ze-Yu Wang <ze-yu.wang@xxxxxxxxxxxx>
+M: Liju Chen <liju-clr.chen@xxxxxxxxxxxx>
+F: Documentation/virt/geniezone/
+
GENWQE (IBM Generic Workqueue Card)
M: Frank Haverkamp <haver@xxxxxxxxxxxxx>
S: Supported
--
2.18.0