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[v8,00/28] Drivers for gunyah hypervisor

Message ID 20221219225850.2397345-1-quic_eberman@quicinc.com
Headers show
Series Drivers for gunyah hypervisor | expand

Message

Elliot Berman Dec. 19, 2022, 10:58 p.m. UTC
Gunyah is a Type-1 hypervisor independent of any
high-level OS kernel, and runs in a higher CPU privilege level. It does
not depend on any lower-privileged OS kernel/code for its core
functionality. This increases its security and can support a much smaller
trusted computing base than a Type-2 hypervisor.

Gunyah is an open source hypervisor. The source repo is available at
https://github.com/quic/gunyah-hypervisor.

The diagram below shows the architecture.

::

         VM A                    VM B
     +-----+ +-----+  | +-----+ +-----+ +-----+
     |     | |     |  | |     | |     | |     |
 EL0 | APP | | APP |  | | APP | | APP | | APP |
     |     | |     |  | |     | |     | |     |
     +-----+ +-----+  | +-----+ +-----+ +-----+
 ---------------------|-------------------------
     +--------------+ | +----------------------+
     |              | | |                      |
 EL1 | Linux Kernel | | |Linux kernel/Other OS |   ...
     |              | | |                      |
     +--------------+ | +----------------------+
 --------hvc/smc------|------hvc/smc------------
     +----------------------------------------+
     |                                        |
 EL2 |            Gunyah Hypervisor           |
     |                                        |
     +----------------------------------------+

Gunyah provides these following features.

- Threads and Scheduling: The scheduler schedules virtual CPUs (VCPUs) on
physical CPUs and enables time-sharing of the CPUs.
- Memory Management: Gunyah tracks memory ownership and use of all memory
under its control. Memory partitioning between VMs is a fundamental
security feature.
- Interrupt Virtualization: All interrupts are handled in the hypervisor
and routed to the assigned VM.
- Inter-VM Communication: There are several different mechanisms provided
for communicating between VMs.
- Device Virtualization: Para-virtualization of devices is supported using
inter-VM communication. Low level system features and devices such as
interrupt controllers are supported with emulation where required.

This series adds the basic framework for detecting that Linux is running
under Gunyah as a virtual machine, communication with the Gunyah Resource
Manager, and a virtual machine manager capable of launching virtual machines.

Patches 21-28 are presently intended to be submitted separately and are included
for initial RFC. These patches introudce "VM function" framework to expose further
interfaces to interact with Gunyah Virtual Machines. With all 28 patches, it is
possible to create a Gunyah VM supporting virtio.

Changes in v8:
 - Treat VM manager as a library of RM
 - Add patches 21-28 as RFC to support proxy-scheduled vCPUs and necessary bits to support virtio
   from Gunyah userspace

Changes in v7: https://lore.kernel.org/all/20221121140009.2353512-1-quic_eberman@quicinc.com/
 - Refactor to remove gunyah RM bus
 - Refactor allow multiple RM device instances
 - Bump UAPI to start at 0x0
 - Refactor QCOM SCM's platform hooks to allow CONFIG_QCOM_SCM=Y/CONFIG_GUNYAH=M combinations

Changes in v6: https://lore.kernel.org/all/20221026185846.3983888-1-quic_eberman@quicinc.com/
 - *Replace gunyah-console with gunyah VM Manager*
 - Move include/asm-generic/gunyah.h into include/linux/gunyah.h
 - s/gunyah_msgq/gh_msgq/
 - Minor tweaks and documentation tidying based on comments from Jiri, Greg, Arnd, Dmitry, and Bagas.

Changes in v5: https://lore.kernel.org/all/20221011000840.289033-1-quic_eberman@quicinc.com/
 - Dropped sysfs nodes
 - Switch from aux bus to Gunyah RM bus for the subdevices
 - Cleaning up RM console

Changes in v4: https://lore.kernel.org/all/20220928195633.2348848-1-quic_eberman@quicinc.com/
 - Tidied up documentation throughout based on questions/feedback received
 - Switched message queue implementation to use mailboxes
 - Renamed "gunyah_device" as "gunyah_resource"

Changes in v3: https://lore.kernel.org/all/20220811214107.1074343-1-quic_eberman@quicinc.com/
 - /Maintained/Supported/ in MAINTAINERS
 - Tidied up documentation throughout based on questions/feedback received
 - Moved hypercalls into arch/arm64/gunyah/; following hyper-v's implementation
 - Drop opaque typedefs
 - Move sysfs nodes under /sys/hypervisor/gunyah/
 - Moved Gunyah console driver to drivers/tty/
 - Reworked gunyah_device design to drop the Gunyah bus.

Changes in v2: https://lore.kernel.org/all/20220801211240.597859-1-quic_eberman@quicinc.com/
 - DT bindings clean up
 - Switch hypercalls to follow SMCCC 

v1: https://lore.kernel.org/all/20220223233729.1571114-1-quic_eberman@quicinc.com/

Elliot Berman (28):
  docs: gunyah: Introduce Gunyah Hypervisor
  dt-bindings: Add binding for gunyah hypervisor
  gunyah: Common types and error codes for Gunyah hypercalls
  arm64: smccc: Include alternative-macros.h
  virt: gunyah: Add hypercalls to identify Gunyah
  virt: gunyah: Identify hypervisor version
  mailbox: Allow direct registration to a channel
  virt: gunyah: msgq: Add hypercalls to send and receive messages
  mailbox: Add Gunyah message queue mailbox
  gunyah: rsc_mgr: Add resource manager RPC core
  gunyah: rsc_mgr: Add VM lifecycle RPC
  gunyah: vm_mgr: Introduce basic VM Manager
  gunyah: rsc_mgr: Add RPC for sharing memory
  gunyah: vm_mgr: Add/remove user memory regions
  gunyah: vm_mgr: Add ioctls to support basic non-proxy VM boot
  samples: Add sample userspace Gunyah VM Manager
  gunyah: rsc_mgr: Add platform ops on mem_lend/mem_reclaim
  firmware: qcom_scm: Use fixed width src vm bitmap
  firmware: qcom_scm: Register Gunyah platform ops
  docs: gunyah: Document Gunyah VM Manager
  virt: gunyah: Translate gh_rm_hyp_resource into gunyah_resource
  gunyah: vm_mgr: Add framework to add VM Functions
  virt: gunyah: Add resource tickets
  virt: gunyah: Add IO handlers
  virt: gunyah: Add proxy-scheduled vCPUs
  virt: gunyah: Add hypercalls for sending doorbell
  virt: gunyah: Add irqfd interface
  virt: gunyah: Add ioeventfd

 .../bindings/firmware/gunyah-hypervisor.yaml  |  82 ++
 .../userspace-api/ioctl/ioctl-number.rst      |   1 +
 Documentation/virt/gunyah/index.rst           | 115 +++
 Documentation/virt/gunyah/message-queue.rst   |  64 ++
 Documentation/virt/gunyah/vm-manager.rst      | 187 ++++
 Documentation/virt/index.rst                  |   1 +
 MAINTAINERS                                   |  13 +
 arch/arm64/Kbuild                             |   1 +
 arch/arm64/gunyah/Makefile                    |   1 +
 arch/arm64/gunyah/gunyah_hypercall.c          | 157 ++++
 arch/arm64/include/asm/gunyah.h               |  23 +
 drivers/firmware/Kconfig                      |   2 +
 drivers/firmware/qcom_scm.c                   | 107 ++-
 drivers/mailbox/Kconfig                       |  10 +
 drivers/mailbox/Makefile                      |   2 +
 drivers/mailbox/gunyah-msgq.c                 | 229 +++++
 drivers/mailbox/mailbox.c                     |  96 ++-
 drivers/mailbox/omap-mailbox.c                |  18 +-
 drivers/mailbox/pcc.c                         |  18 +-
 drivers/misc/fastrpc.c                        |   6 +-
 drivers/net/wireless/ath/ath10k/qmi.c         |   4 +-
 drivers/remoteproc/qcom_q6v5_mss.c            |   8 +-
 drivers/soc/qcom/rmtfs_mem.c                  |   2 +-
 drivers/virt/Kconfig                          |   1 +
 drivers/virt/Makefile                         |   1 +
 drivers/virt/gunyah/Kconfig                   |  73 ++
 drivers/virt/gunyah/Makefile                  |  10 +
 drivers/virt/gunyah/gunyah.c                  |  46 +
 drivers/virt/gunyah/gunyah_ioeventfd.c        | 109 +++
 drivers/virt/gunyah/gunyah_irqfd.c            | 180 ++++
 drivers/virt/gunyah/gunyah_platform_hooks.c   |  63 ++
 drivers/virt/gunyah/gunyah_vcpu.c             | 350 ++++++++
 drivers/virt/gunyah/rsc_mgr.c                 | 795 ++++++++++++++++++
 drivers/virt/gunyah/rsc_mgr.h                 | 124 +++
 drivers/virt/gunyah/rsc_mgr_rpc.c             | 428 ++++++++++
 drivers/virt/gunyah/vm_mgr.c                  | 594 +++++++++++++
 drivers/virt/gunyah/vm_mgr.h                  |  76 ++
 drivers/virt/gunyah/vm_mgr_mm.c               | 245 ++++++
 include/linux/arm-smccc.h                     |   1 +
 include/linux/gunyah.h                        | 186 ++++
 include/linux/gunyah_rsc_mgr.h                | 136 +++
 include/linux/gunyah_vm_mgr.h                 | 107 +++
 include/linux/mailbox_client.h                |   1 +
 include/linux/qcom_scm.h                      |   2 +-
 include/uapi/linux/gunyah.h                   | 114 +++
 samples/Kconfig                               |  10 +
 samples/Makefile                              |   1 +
 samples/gunyah/.gitignore                     |   2 +
 samples/gunyah/Makefile                       |   6 +
 samples/gunyah/gunyah_vmm.c                   | 270 ++++++
 samples/gunyah/sample_vm.dts                  |  69 ++
 51 files changed, 5075 insertions(+), 72 deletions(-)
 create mode 100644 Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
 create mode 100644 Documentation/virt/gunyah/index.rst
 create mode 100644 Documentation/virt/gunyah/message-queue.rst
 create mode 100644 Documentation/virt/gunyah/vm-manager.rst
 create mode 100644 arch/arm64/gunyah/Makefile
 create mode 100644 arch/arm64/gunyah/gunyah_hypercall.c
 create mode 100644 arch/arm64/include/asm/gunyah.h
 create mode 100644 drivers/mailbox/gunyah-msgq.c
 create mode 100644 drivers/virt/gunyah/Kconfig
 create mode 100644 drivers/virt/gunyah/Makefile
 create mode 100644 drivers/virt/gunyah/gunyah.c
 create mode 100644 drivers/virt/gunyah/gunyah_ioeventfd.c
 create mode 100644 drivers/virt/gunyah/gunyah_irqfd.c
 create mode 100644 drivers/virt/gunyah/gunyah_platform_hooks.c
 create mode 100644 drivers/virt/gunyah/gunyah_vcpu.c
 create mode 100644 drivers/virt/gunyah/rsc_mgr.c
 create mode 100644 drivers/virt/gunyah/rsc_mgr.h
 create mode 100644 drivers/virt/gunyah/rsc_mgr_rpc.c
 create mode 100644 drivers/virt/gunyah/vm_mgr.c
 create mode 100644 drivers/virt/gunyah/vm_mgr.h
 create mode 100644 drivers/virt/gunyah/vm_mgr_mm.c
 create mode 100644 include/linux/gunyah.h
 create mode 100644 include/linux/gunyah_rsc_mgr.h
 create mode 100644 include/linux/gunyah_vm_mgr.h
 create mode 100644 include/uapi/linux/gunyah.h
 create mode 100644 samples/gunyah/.gitignore
 create mode 100644 samples/gunyah/Makefile
 create mode 100644 samples/gunyah/gunyah_vmm.c
 create mode 100644 samples/gunyah/sample_vm.dts


base-commit: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476

Comments

Alex Elder Jan. 9, 2023, 9:34 p.m. UTC | #1
On 12/19/22 4:58 PM, Elliot Berman wrote:
> Gunyah is a Type-1 hypervisor independent of any
> high-level OS kernel, and runs in a higher CPU privilege level. It does
> not depend on any lower-privileged OS kernel/code for its core
> functionality. This increases its security and can support a much smaller
> trusted computing base than a Type-2 hypervisor.
> 
> Gunyah is an open source hypervisor. The source repo is available at
> https://github.com/quic/gunyah-hypervisor.

Can you provide any history about the hypervisor code itself?
Was it publicly reviewed?  Has it been reviewed by anyone in
the Linux kernel community, who might have some useful input
on it?

> The diagram below shows the architecture.
> 
> ::
> 
>           VM A                    VM B
>       +-----+ +-----+  | +-----+ +-----+ +-----+
>       |     | |     |  | |     | |     | |     |
>   EL0 | APP | | APP |  | | APP | | APP | | APP |
>       |     | |     |  | |     | |     | |     |
>       +-----+ +-----+  | +-----+ +-----+ +-----+
>   ---------------------|-------------------------
>       +--------------+ | +----------------------+
>       |              | | |                      |
>   EL1 | Linux Kernel | | |Linux kernel/Other OS |   ...
>       |              | | |                      |
>       +--------------+ | +----------------------+
>   --------hvc/smc------|------hvc/smc------------
>       +----------------------------------------+
>       |                                        |
>   EL2 |            Gunyah Hypervisor           |
>       |                                        |
>       +----------------------------------------+
> 
> Gunyah provides these following features.
> 
> - Threads and Scheduling: The scheduler schedules virtual CPUs (VCPUs) on
> physical CPUs and enables time-sharing of the CPUs.
> - Memory Management: Gunyah tracks memory ownership and use of all memory
> under its control. Memory partitioning between VMs is a fundamental
> security feature.
> - Interrupt Virtualization: All interrupts are handled in the hypervisor
> and routed to the assigned VM.
> - Inter-VM Communication: There are several different mechanisms provided
> for communicating between VMs.
> - Device Virtualization: Para-virtualization of devices is supported using
> inter-VM communication. Low level system features and devices such as
> interrupt controllers are supported with emulation where required.
> 
> This series adds the basic framework for detecting that Linux is running
> under Gunyah as a virtual machine, communication with the Gunyah Resource
> Manager, and a virtual machine manager capable of launching virtual machines.
> 
> Patches 21-28 are presently intended to be submitted separately and are included
> for initial RFC. These patches introudce "VM function" framework to expose further
> interfaces to interact with Gunyah Virtual Machines. With all 28 patches, it is
> possible to create a Gunyah VM supporting virtio.

I'm not a virtualization expert, and it's likely some of my
comments demonstrate that...

You're going to need to update your copyright dates to include
2023 now.

I haven't looked at the earlier reviews; perhaps the RFC stuff
was requested.  I'm sure it's useful to see that but it doesn't
seem directly helpful if your goal is to get this code upstream.

At this point I've reviewed only through patch 9.  I currently
have smallish blocks of time and I don't want to hold back my
feedback for too long.

					-Alex

> Changes in v8:
>   - Treat VM manager as a library of RM
>   - Add patches 21-28 as RFC to support proxy-scheduled vCPUs and necessary bits to support virtio
>     from Gunyah userspace
> 
> Changes in v7: https://lore.kernel.org/all/20221121140009.2353512-1-quic_eberman@quicinc.com/
>   - Refactor to remove gunyah RM bus
>   - Refactor allow multiple RM device instances
>   - Bump UAPI to start at 0x0
>   - Refactor QCOM SCM's platform hooks to allow CONFIG_QCOM_SCM=Y/CONFIG_GUNYAH=M combinations
> 
> Changes in v6: https://lore.kernel.org/all/20221026185846.3983888-1-quic_eberman@quicinc.com/
>   - *Replace gunyah-console with gunyah VM Manager*
>   - Move include/asm-generic/gunyah.h into include/linux/gunyah.h
>   - s/gunyah_msgq/gh_msgq/
>   - Minor tweaks and documentation tidying based on comments from Jiri, Greg, Arnd, Dmitry, and Bagas.
> 
> Changes in v5: https://lore.kernel.org/all/20221011000840.289033-1-quic_eberman@quicinc.com/
>   - Dropped sysfs nodes
>   - Switch from aux bus to Gunyah RM bus for the subdevices
>   - Cleaning up RM console
> 
> Changes in v4: https://lore.kernel.org/all/20220928195633.2348848-1-quic_eberman@quicinc.com/
>   - Tidied up documentation throughout based on questions/feedback received
>   - Switched message queue implementation to use mailboxes
>   - Renamed "gunyah_device" as "gunyah_resource"
> 
> Changes in v3: https://lore.kernel.org/all/20220811214107.1074343-1-quic_eberman@quicinc.com/
>   - /Maintained/Supported/ in MAINTAINERS
>   - Tidied up documentation throughout based on questions/feedback received
>   - Moved hypercalls into arch/arm64/gunyah/; following hyper-v's implementation
>   - Drop opaque typedefs
>   - Move sysfs nodes under /sys/hypervisor/gunyah/
>   - Moved Gunyah console driver to drivers/tty/
>   - Reworked gunyah_device design to drop the Gunyah bus.
> 
> Changes in v2: https://lore.kernel.org/all/20220801211240.597859-1-quic_eberman@quicinc.com/
>   - DT bindings clean up
>   - Switch hypercalls to follow SMCCC
> 
> v1: https://lore.kernel.org/all/20220223233729.1571114-1-quic_eberman@quicinc.com/
> 
> Elliot Berman (28):
>    docs: gunyah: Introduce Gunyah Hypervisor
>    dt-bindings: Add binding for gunyah hypervisor
>    gunyah: Common types and error codes for Gunyah hypercalls
>    arm64: smccc: Include alternative-macros.h
>    virt: gunyah: Add hypercalls to identify Gunyah
>    virt: gunyah: Identify hypervisor version
>    mailbox: Allow direct registration to a channel
>    virt: gunyah: msgq: Add hypercalls to send and receive messages
>    mailbox: Add Gunyah message queue mailbox
>    gunyah: rsc_mgr: Add resource manager RPC core
>    gunyah: rsc_mgr: Add VM lifecycle RPC
>    gunyah: vm_mgr: Introduce basic VM Manager
>    gunyah: rsc_mgr: Add RPC for sharing memory
>    gunyah: vm_mgr: Add/remove user memory regions
>    gunyah: vm_mgr: Add ioctls to support basic non-proxy VM boot
>    samples: Add sample userspace Gunyah VM Manager
>    gunyah: rsc_mgr: Add platform ops on mem_lend/mem_reclaim
>    firmware: qcom_scm: Use fixed width src vm bitmap
>    firmware: qcom_scm: Register Gunyah platform ops
>    docs: gunyah: Document Gunyah VM Manager
>    virt: gunyah: Translate gh_rm_hyp_resource into gunyah_resource
>    gunyah: vm_mgr: Add framework to add VM Functions
>    virt: gunyah: Add resource tickets
>    virt: gunyah: Add IO handlers
>    virt: gunyah: Add proxy-scheduled vCPUs
>    virt: gunyah: Add hypercalls for sending doorbell
>    virt: gunyah: Add irqfd interface
>    virt: gunyah: Add ioeventfd
> 
>   .../bindings/firmware/gunyah-hypervisor.yaml  |  82 ++
>   .../userspace-api/ioctl/ioctl-number.rst      |   1 +
>   Documentation/virt/gunyah/index.rst           | 115 +++
>   Documentation/virt/gunyah/message-queue.rst   |  64 ++
>   Documentation/virt/gunyah/vm-manager.rst      | 187 ++++
>   Documentation/virt/index.rst                  |   1 +
>   MAINTAINERS                                   |  13 +
>   arch/arm64/Kbuild                             |   1 +
>   arch/arm64/gunyah/Makefile                    |   1 +
>   arch/arm64/gunyah/gunyah_hypercall.c          | 157 ++++
>   arch/arm64/include/asm/gunyah.h               |  23 +
>   drivers/firmware/Kconfig                      |   2 +
>   drivers/firmware/qcom_scm.c                   | 107 ++-
>   drivers/mailbox/Kconfig                       |  10 +
>   drivers/mailbox/Makefile                      |   2 +
>   drivers/mailbox/gunyah-msgq.c                 | 229 +++++
>   drivers/mailbox/mailbox.c                     |  96 ++-
>   drivers/mailbox/omap-mailbox.c                |  18 +-
>   drivers/mailbox/pcc.c                         |  18 +-
>   drivers/misc/fastrpc.c                        |   6 +-
>   drivers/net/wireless/ath/ath10k/qmi.c         |   4 +-
>   drivers/remoteproc/qcom_q6v5_mss.c            |   8 +-
>   drivers/soc/qcom/rmtfs_mem.c                  |   2 +-
>   drivers/virt/Kconfig                          |   1 +
>   drivers/virt/Makefile                         |   1 +
>   drivers/virt/gunyah/Kconfig                   |  73 ++
>   drivers/virt/gunyah/Makefile                  |  10 +
>   drivers/virt/gunyah/gunyah.c                  |  46 +
>   drivers/virt/gunyah/gunyah_ioeventfd.c        | 109 +++
>   drivers/virt/gunyah/gunyah_irqfd.c            | 180 ++++
>   drivers/virt/gunyah/gunyah_platform_hooks.c   |  63 ++
>   drivers/virt/gunyah/gunyah_vcpu.c             | 350 ++++++++
>   drivers/virt/gunyah/rsc_mgr.c                 | 795 ++++++++++++++++++
>   drivers/virt/gunyah/rsc_mgr.h                 | 124 +++
>   drivers/virt/gunyah/rsc_mgr_rpc.c             | 428 ++++++++++
>   drivers/virt/gunyah/vm_mgr.c                  | 594 +++++++++++++
>   drivers/virt/gunyah/vm_mgr.h                  |  76 ++
>   drivers/virt/gunyah/vm_mgr_mm.c               | 245 ++++++
>   include/linux/arm-smccc.h                     |   1 +
>   include/linux/gunyah.h                        | 186 ++++
>   include/linux/gunyah_rsc_mgr.h                | 136 +++
>   include/linux/gunyah_vm_mgr.h                 | 107 +++
>   include/linux/mailbox_client.h                |   1 +
>   include/linux/qcom_scm.h                      |   2 +-
>   include/uapi/linux/gunyah.h                   | 114 +++
>   samples/Kconfig                               |  10 +
>   samples/Makefile                              |   1 +
>   samples/gunyah/.gitignore                     |   2 +
>   samples/gunyah/Makefile                       |   6 +
>   samples/gunyah/gunyah_vmm.c                   | 270 ++++++
>   samples/gunyah/sample_vm.dts                  |  69 ++
>   51 files changed, 5075 insertions(+), 72 deletions(-)
>   create mode 100644 Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
>   create mode 100644 Documentation/virt/gunyah/index.rst
>   create mode 100644 Documentation/virt/gunyah/message-queue.rst
>   create mode 100644 Documentation/virt/gunyah/vm-manager.rst
>   create mode 100644 arch/arm64/gunyah/Makefile
>   create mode 100644 arch/arm64/gunyah/gunyah_hypercall.c
>   create mode 100644 arch/arm64/include/asm/gunyah.h
>   create mode 100644 drivers/mailbox/gunyah-msgq.c
>   create mode 100644 drivers/virt/gunyah/Kconfig
>   create mode 100644 drivers/virt/gunyah/Makefile
>   create mode 100644 drivers/virt/gunyah/gunyah.c
>   create mode 100644 drivers/virt/gunyah/gunyah_ioeventfd.c
>   create mode 100644 drivers/virt/gunyah/gunyah_irqfd.c
>   create mode 100644 drivers/virt/gunyah/gunyah_platform_hooks.c
>   create mode 100644 drivers/virt/gunyah/gunyah_vcpu.c
>   create mode 100644 drivers/virt/gunyah/rsc_mgr.c
>   create mode 100644 drivers/virt/gunyah/rsc_mgr.h
>   create mode 100644 drivers/virt/gunyah/rsc_mgr_rpc.c
>   create mode 100644 drivers/virt/gunyah/vm_mgr.c
>   create mode 100644 drivers/virt/gunyah/vm_mgr.h
>   create mode 100644 drivers/virt/gunyah/vm_mgr_mm.c
>   create mode 100644 include/linux/gunyah.h
>   create mode 100644 include/linux/gunyah_rsc_mgr.h
>   create mode 100644 include/linux/gunyah_vm_mgr.h
>   create mode 100644 include/uapi/linux/gunyah.h
>   create mode 100644 samples/gunyah/.gitignore
>   create mode 100644 samples/gunyah/Makefile
>   create mode 100644 samples/gunyah/gunyah_vmm.c
>   create mode 100644 samples/gunyah/sample_vm.dts
> 
> 
> base-commit: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476
Elliot Berman Jan. 10, 2023, 5:54 p.m. UTC | #2
On 1/9/2023 1:34 PM, Alex Elder wrote:
> On 12/19/22 4:58 PM, Elliot Berman wrote:
>> Gunyah is a Type-1 hypervisor independent of any
>> high-level OS kernel, and runs in a higher CPU privilege level. It does
>> not depend on any lower-privileged OS kernel/code for its core
>> functionality. This increases its security and can support a much smaller
>> trusted computing base than a Type-2 hypervisor.
>>
>> Gunyah is an open source hypervisor. The source repo is available at
>> https://github.com/quic/gunyah-hypervisor.
> 
> Can you provide any history about the hypervisor code itself?
> Was it publicly reviewed?  Has it been reviewed by anyone in
> the Linux kernel community, who might have some useful input
> on it?
> 

This is Gunyah's first interaction with wider public community. Gunyah 
has been deployed in devices for past few generation of Qualcomm 
Technolgoies, Inc. (mobile) chipsets.

Thanks,
Elliot
Elliot Berman Jan. 10, 2023, 9:47 p.m. UTC | #3
On 1/9/2023 1:34 PM, Alex Elder wrote:
> On 12/19/22 4:58 PM, Elliot Berman wrote:
>> Gunyah is a Type-1 hypervisor independent of any
>> high-level OS kernel, and runs in a higher CPU privilege level. It does
>> not depend on any lower-privileged OS kernel/code for its core
>> functionality. This increases its security and can support a much smaller
>> trusted computing base than a Type-2 hypervisor.
>>
>> Gunyah is an open source hypervisor. The source repo is available at
>> https://github.com/quic/gunyah-hypervisor.
> 
> Can you provide any history about the hypervisor code itself?
> Was it publicly reviewed?  Has it been reviewed by anyone in
> the Linux kernel community, who might have some useful input
> on it?
> 
>> The diagram below shows the architecture.
>>
>> ::
>>
>>           VM A                    VM B
>>       +-----+ +-----+  | +-----+ +-----+ +-----+
>>       |     | |     |  | |     | |     | |     |
>>   EL0 | APP | | APP |  | | APP | | APP | | APP |
>>       |     | |     |  | |     | |     | |     |
>>       +-----+ +-----+  | +-----+ +-----+ +-----+
>>   ---------------------|-------------------------
>>       +--------------+ | +----------------------+
>>       |              | | |                      |
>>   EL1 | Linux Kernel | | |Linux kernel/Other OS |   ...
>>       |              | | |                      |
>>       +--------------+ | +----------------------+
>>   --------hvc/smc------|------hvc/smc------------
>>       +----------------------------------------+
>>       |                                        |
>>   EL2 |            Gunyah Hypervisor           |
>>       |                                        |
>>       +----------------------------------------+
>>
>> Gunyah provides these following features.
>>
>> - Threads and Scheduling: The scheduler schedules virtual CPUs (VCPUs) on
>> physical CPUs and enables time-sharing of the CPUs.
>> - Memory Management: Gunyah tracks memory ownership and use of all memory
>> under its control. Memory partitioning between VMs is a fundamental
>> security feature.
>> - Interrupt Virtualization: All interrupts are handled in the hypervisor
>> and routed to the assigned VM.
>> - Inter-VM Communication: There are several different mechanisms provided
>> for communicating between VMs.
>> - Device Virtualization: Para-virtualization of devices is supported 
>> using
>> inter-VM communication. Low level system features and devices such as
>> interrupt controllers are supported with emulation where required.
>>
>> This series adds the basic framework for detecting that Linux is running
>> under Gunyah as a virtual machine, communication with the Gunyah Resource
>> Manager, and a virtual machine manager capable of launching virtual 
>> machines.
>>
>> Patches 21-28 are presently intended to be submitted separately and 
>> are included
>> for initial RFC. These patches introudce "VM function" framework to 
>> expose further
>> interfaces to interact with Gunyah Virtual Machines. With all 28 
>> patches, it is
>> possible to create a Gunyah VM supporting virtio.
> 
> I'm not a virtualization expert, and it's likely some of my
> comments demonstrate that...
> 
> You're going to need to update your copyright dates to include
> 2023 now.
> 
> I haven't looked at the earlier reviews; perhaps the RFC stuff
> was requested.  I'm sure it's useful to see that but it doesn't
> seem directly helpful if your goal is to get this code upstream.
> 

Right, the RFC patches were requested. Do you have a recommendation for 
sharing those later patches? I understand it's best practice not to post 
too many patches. The logical split was to have 1-20 go in first, and 
the remaining patches submitted later.

> At this point I've reviewed only through patch 9.  I currently
> have smallish blocks of time and I don't want to hold back my
> feedback for too long.
> 
>                      -Alex
> 
>> Changes in v8:
>>   - Treat VM manager as a library of RM
>>   - Add patches 21-28 as RFC to support proxy-scheduled vCPUs and 
>> necessary bits to support virtio
>>     from Gunyah userspace
>>
>> Changes in v7: 
>> https://lore.kernel.org/all/20221121140009.2353512-1-quic_eberman@quicinc.com/
>>   - Refactor to remove gunyah RM bus
>>   - Refactor allow multiple RM device instances
>>   - Bump UAPI to start at 0x0
>>   - Refactor QCOM SCM's platform hooks to allow 
>> CONFIG_QCOM_SCM=Y/CONFIG_GUNYAH=M combinations
>>
>> Changes in v6: 
>> https://lore.kernel.org/all/20221026185846.3983888-1-quic_eberman@quicinc.com/
>>   - *Replace gunyah-console with gunyah VM Manager*
>>   - Move include/asm-generic/gunyah.h into include/linux/gunyah.h
>>   - s/gunyah_msgq/gh_msgq/
>>   - Minor tweaks and documentation tidying based on comments from 
>> Jiri, Greg, Arnd, Dmitry, and Bagas.
>>
>> Changes in v5: 
>> https://lore.kernel.org/all/20221011000840.289033-1-quic_eberman@quicinc.com/
>>   - Dropped sysfs nodes
>>   - Switch from aux bus to Gunyah RM bus for the subdevices
>>   - Cleaning up RM console
>>
>> Changes in v4: 
>> https://lore.kernel.org/all/20220928195633.2348848-1-quic_eberman@quicinc.com/
>>   - Tidied up documentation throughout based on questions/feedback 
>> received
>>   - Switched message queue implementation to use mailboxes
>>   - Renamed "gunyah_device" as "gunyah_resource"
>>
>> Changes in v3: 
>> https://lore.kernel.org/all/20220811214107.1074343-1-quic_eberman@quicinc.com/
>>   - /Maintained/Supported/ in MAINTAINERS
>>   - Tidied up documentation throughout based on questions/feedback 
>> received
>>   - Moved hypercalls into arch/arm64/gunyah/; following hyper-v's 
>> implementation
>>   - Drop opaque typedefs
>>   - Move sysfs nodes under /sys/hypervisor/gunyah/
>>   - Moved Gunyah console driver to drivers/tty/
>>   - Reworked gunyah_device design to drop the Gunyah bus.
>>
>> Changes in v2: 
>> https://lore.kernel.org/all/20220801211240.597859-1-quic_eberman@quicinc.com/
>>   - DT bindings clean up
>>   - Switch hypercalls to follow SMCCC
>>
>> v1: 
>> https://lore.kernel.org/all/20220223233729.1571114-1-quic_eberman@quicinc.com/
>>
>> Elliot Berman (28):
>>    docs: gunyah: Introduce Gunyah Hypervisor
>>    dt-bindings: Add binding for gunyah hypervisor
>>    gunyah: Common types and error codes for Gunyah hypercalls
>>    arm64: smccc: Include alternative-macros.h
>>    virt: gunyah: Add hypercalls to identify Gunyah
>>    virt: gunyah: Identify hypervisor version
>>    mailbox: Allow direct registration to a channel
>>    virt: gunyah: msgq: Add hypercalls to send and receive messages
>>    mailbox: Add Gunyah message queue mailbox
>>    gunyah: rsc_mgr: Add resource manager RPC core
>>    gunyah: rsc_mgr: Add VM lifecycle RPC
>>    gunyah: vm_mgr: Introduce basic VM Manager
>>    gunyah: rsc_mgr: Add RPC for sharing memory
>>    gunyah: vm_mgr: Add/remove user memory regions
>>    gunyah: vm_mgr: Add ioctls to support basic non-proxy VM boot
>>    samples: Add sample userspace Gunyah VM Manager
>>    gunyah: rsc_mgr: Add platform ops on mem_lend/mem_reclaim
>>    firmware: qcom_scm: Use fixed width src vm bitmap
>>    firmware: qcom_scm: Register Gunyah platform ops
>>    docs: gunyah: Document Gunyah VM Manager
>>    virt: gunyah: Translate gh_rm_hyp_resource into gunyah_resource
>>    gunyah: vm_mgr: Add framework to add VM Functions
>>    virt: gunyah: Add resource tickets
>>    virt: gunyah: Add IO handlers
>>    virt: gunyah: Add proxy-scheduled vCPUs
>>    virt: gunyah: Add hypercalls for sending doorbell
>>    virt: gunyah: Add irqfd interface
>>    virt: gunyah: Add ioeventfd
>>
>>   .../bindings/firmware/gunyah-hypervisor.yaml  |  82 ++
>>   .../userspace-api/ioctl/ioctl-number.rst      |   1 +
>>   Documentation/virt/gunyah/index.rst           | 115 +++
>>   Documentation/virt/gunyah/message-queue.rst   |  64 ++
>>   Documentation/virt/gunyah/vm-manager.rst      | 187 ++++
>>   Documentation/virt/index.rst                  |   1 +
>>   MAINTAINERS                                   |  13 +
>>   arch/arm64/Kbuild                             |   1 +
>>   arch/arm64/gunyah/Makefile                    |   1 +
>>   arch/arm64/gunyah/gunyah_hypercall.c          | 157 ++++
>>   arch/arm64/include/asm/gunyah.h               |  23 +
>>   drivers/firmware/Kconfig                      |   2 +
>>   drivers/firmware/qcom_scm.c                   | 107 ++-
>>   drivers/mailbox/Kconfig                       |  10 +
>>   drivers/mailbox/Makefile                      |   2 +
>>   drivers/mailbox/gunyah-msgq.c                 | 229 +++++
>>   drivers/mailbox/mailbox.c                     |  96 ++-
>>   drivers/mailbox/omap-mailbox.c                |  18 +-
>>   drivers/mailbox/pcc.c                         |  18 +-
>>   drivers/misc/fastrpc.c                        |   6 +-
>>   drivers/net/wireless/ath/ath10k/qmi.c         |   4 +-
>>   drivers/remoteproc/qcom_q6v5_mss.c            |   8 +-
>>   drivers/soc/qcom/rmtfs_mem.c                  |   2 +-
>>   drivers/virt/Kconfig                          |   1 +
>>   drivers/virt/Makefile                         |   1 +
>>   drivers/virt/gunyah/Kconfig                   |  73 ++
>>   drivers/virt/gunyah/Makefile                  |  10 +
>>   drivers/virt/gunyah/gunyah.c                  |  46 +
>>   drivers/virt/gunyah/gunyah_ioeventfd.c        | 109 +++
>>   drivers/virt/gunyah/gunyah_irqfd.c            | 180 ++++
>>   drivers/virt/gunyah/gunyah_platform_hooks.c   |  63 ++
>>   drivers/virt/gunyah/gunyah_vcpu.c             | 350 ++++++++
>>   drivers/virt/gunyah/rsc_mgr.c                 | 795 ++++++++++++++++++
>>   drivers/virt/gunyah/rsc_mgr.h                 | 124 +++
>>   drivers/virt/gunyah/rsc_mgr_rpc.c             | 428 ++++++++++
>>   drivers/virt/gunyah/vm_mgr.c                  | 594 +++++++++++++
>>   drivers/virt/gunyah/vm_mgr.h                  |  76 ++
>>   drivers/virt/gunyah/vm_mgr_mm.c               | 245 ++++++
>>   include/linux/arm-smccc.h                     |   1 +
>>   include/linux/gunyah.h                        | 186 ++++
>>   include/linux/gunyah_rsc_mgr.h                | 136 +++
>>   include/linux/gunyah_vm_mgr.h                 | 107 +++
>>   include/linux/mailbox_client.h                |   1 +
>>   include/linux/qcom_scm.h                      |   2 +-
>>   include/uapi/linux/gunyah.h                   | 114 +++
>>   samples/Kconfig                               |  10 +
>>   samples/Makefile                              |   1 +
>>   samples/gunyah/.gitignore                     |   2 +
>>   samples/gunyah/Makefile                       |   6 +
>>   samples/gunyah/gunyah_vmm.c                   | 270 ++++++
>>   samples/gunyah/sample_vm.dts                  |  69 ++
>>   51 files changed, 5075 insertions(+), 72 deletions(-)
>>   create mode 100644 
>> Documentation/devicetree/bindings/firmware/gunyah-hypervisor.yaml
>>   create mode 100644 Documentation/virt/gunyah/index.rst
>>   create mode 100644 Documentation/virt/gunyah/message-queue.rst
>>   create mode 100644 Documentation/virt/gunyah/vm-manager.rst
>>   create mode 100644 arch/arm64/gunyah/Makefile
>>   create mode 100644 arch/arm64/gunyah/gunyah_hypercall.c
>>   create mode 100644 arch/arm64/include/asm/gunyah.h
>>   create mode 100644 drivers/mailbox/gunyah-msgq.c
>>   create mode 100644 drivers/virt/gunyah/Kconfig
>>   create mode 100644 drivers/virt/gunyah/Makefile
>>   create mode 100644 drivers/virt/gunyah/gunyah.c
>>   create mode 100644 drivers/virt/gunyah/gunyah_ioeventfd.c
>>   create mode 100644 drivers/virt/gunyah/gunyah_irqfd.c
>>   create mode 100644 drivers/virt/gunyah/gunyah_platform_hooks.c
>>   create mode 100644 drivers/virt/gunyah/gunyah_vcpu.c
>>   create mode 100644 drivers/virt/gunyah/rsc_mgr.c
>>   create mode 100644 drivers/virt/gunyah/rsc_mgr.h
>>   create mode 100644 drivers/virt/gunyah/rsc_mgr_rpc.c
>>   create mode 100644 drivers/virt/gunyah/vm_mgr.c
>>   create mode 100644 drivers/virt/gunyah/vm_mgr.h
>>   create mode 100644 drivers/virt/gunyah/vm_mgr_mm.c
>>   create mode 100644 include/linux/gunyah.h
>>   create mode 100644 include/linux/gunyah_rsc_mgr.h
>>   create mode 100644 include/linux/gunyah_vm_mgr.h
>>   create mode 100644 include/uapi/linux/gunyah.h
>>   create mode 100644 samples/gunyah/.gitignore
>>   create mode 100644 samples/gunyah/Makefile
>>   create mode 100644 samples/gunyah/gunyah_vmm.c
>>   create mode 100644 samples/gunyah/sample_vm.dts
>>
>>
>> base-commit: 830b3c68c1fb1e9176028d02ef86f3cf76aa2476
>
Alex Elder Jan. 17, 2023, 7:20 p.m. UTC | #4
On 1/10/23 3:47 PM, Elliot Berman wrote:
>>
>> I haven't looked at the earlier reviews; perhaps the RFC stuff
>> was requested.  I'm sure it's useful to see that but it doesn't
>> seem directly helpful if your goal is to get this code upstream.
>>
> 
> Right, the RFC patches were requested. Do you have a recommendation for 
> sharing those later patches? I understand it's best practice not to post 
> too many patches. The logical split was to have 1-20 go in first, and 
> the remaining patches submitted later.

If they're RFC they should be tagged "RFC".

I do think it's easier for reviewers if you can divide up the
code into a few smaller series, so reviewing each (sub-)series
isn't such an overwhelming thing to consider.  I've started
looking (IN GREAT DETAIL) the RPC core code, and haven't gone
much past that, so I don't have any guidance about how things
could be structured.  (I do appreciate that the early patches
were small, and built things up gradually.)

I personally try to keep my series to closer to 5-10 patches,
though the maintainer(s) involved need to agree to accept the
smaller series before the full functionality gets enabled when
it's all accepted.

You'll get (lots) more feedback from me on the remaining patches,
eventually.  If you decide to re-spin things soon I'd like to know
your plan so I can review the latest when it's available.

					-Alex