[PATCH v2 0/6] virt: Add Bao hypervisor IPC and I/O dispatcher drivers

[Greg KH]

On Wed, Jan 07, 2026 at 04:28:23PM +0000, joaopeixoto at osyx.tech wrote:
> From: João Peixoto <joaopeixoto at osyx.tech>
> 
> This series introduces support for Bao hypervisor guest-side drivers
> under drivers/virt/bao, along with the associated Device Tree bindings,
> UAPI headers, and MAINTAINERS entries.
> 
> Bao is a lightweight static-partitioning hypervisor for embedded and
> safety-critical systems. This series adds:
> - Bao IPC shared memory driver: Enables Linux guests to communicate
> with each other via shared memory regions.
> - Bao I/O Dispatcher driver: Allows Bao VMs to share I/O devices using
> device paravirtualization (VirtIO).
> 
> Key updates in this version to align with upstream requirements:
> 1. Switched to misc device API: Removed all cdev, class, and
> alloc_chrdev_region code in favor of misc_register() for simpler,
> standard device management.
> 2. Clean kernel style and formatting: All code passes checkpatch.pl,
> with consistent variable declaration, function naming, and comment style.
> 3. Architecture abstraction: Consolidated ARM, ARM64, and RISC-V hypercall
> logic into architecture-specific headers, removing in-driver #ifdefs.
> 4. Commit messages: Now concise and Linux-kernel-style, describing
> behavior and impact clearly.
> 5. Device Tree compliance: Fixed all make dt_binding_check errors to
> ensure DT binding correctness.
> 
> This series has been validated on Linux guests running under Bao
> hypervisor, confirming correct initialization, IPC shared-memory
> read/write operations, and I/O Dispatcher functionality for
> backend VMs.
> 
> Feedback and review from maintainers of virtualization,
> architecture-specific code (ARM, ARM64, RISC-V), Device Tree
> bindings, and UAPI are welcome.
> 
> João Peixoto (6):
>   dt-bindings: Add Bao IPC shared memory driver binding
>   virt: bao: Add Bao IPC shared memory driver
>   dt-bindings: Add Bao I/O dispatcher driver binding
>   virt: bao: Add Bao I/O dispatcher driver
>   virt: bao: Move BAO_IPCSHMEM_HYPERCALL_ID to common header
>   MAINTAINERS: Add entries for Bao hypervisor drivers, headers, and DT
>     bindings
> 
>  .../bindings/bao/bao,io-dispatcher.yaml       |  75 ++++
>  .../devicetree/bindings/bao/bao,ipcshmem.yaml |  82 ++++
>  .../devicetree/bindings/vendor-prefixes.yaml  |   2 +
>  .../userspace-api/ioctl/ioctl-number.rst      |   2 +
>  MAINTAINERS                                   |  13 +
>  arch/arm/include/asm/bao.h                    |  60 +++
>  arch/arm64/include/asm/bao.h                  |  60 +++
>  arch/riscv/include/asm/bao.h                  |  60 +++
>  drivers/virt/Kconfig                          |   2 +
>  drivers/virt/Makefile                         |   2 +
>  drivers/virt/bao/Kconfig                      |   5 +
>  drivers/virt/bao/Makefile                     |   4 +
>  drivers/virt/bao/io-dispatcher/Kconfig        |  15 +
>  drivers/virt/bao/io-dispatcher/Makefile       |   4 +
>  drivers/virt/bao/io-dispatcher/bao_drv.h      | 361 ++++++++++++++++
>  drivers/virt/bao/io-dispatcher/dm.c           | 405 ++++++++++++++++++
>  drivers/virt/bao/io-dispatcher/driver.c       | 185 ++++++++
>  drivers/virt/bao/io-dispatcher/intc.c         |  64 +++
>  drivers/virt/bao/io-dispatcher/io_client.c    | 405 ++++++++++++++++++
>  .../virt/bao/io-dispatcher/io_dispatcher.c    | 179 ++++++++
>  drivers/virt/bao/io-dispatcher/ioeventfd.c    | 323 ++++++++++++++
>  drivers/virt/bao/io-dispatcher/irqfd.c        | 314 ++++++++++++++
>  drivers/virt/bao/ipcshmem/Kconfig             |   8 +
>  drivers/virt/bao/ipcshmem/Makefile            |   3 +
>  drivers/virt/bao/ipcshmem/ipcshmem.c          | 252 +++++++++++
>  include/linux/bao.h                           |  44 ++
>  include/uapi/linux/bao.h                      |  98 +++++
>  27 files changed, 3027 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/bao/bao,io-dispatcher.yaml
>  create mode 100644 Documentation/devicetree/bindings/bao/bao,ipcshmem.yaml
>  create mode 100644 arch/arm/include/asm/bao.h
>  create mode 100644 arch/arm64/include/asm/bao.h
>  create mode 100644 arch/riscv/include/asm/bao.h
>  create mode 100644 drivers/virt/bao/Kconfig
>  create mode 100644 drivers/virt/bao/Makefile
>  create mode 100644 drivers/virt/bao/io-dispatcher/Kconfig
>  create mode 100644 drivers/virt/bao/io-dispatcher/Makefile
>  create mode 100644 drivers/virt/bao/io-dispatcher/bao_drv.h
>  create mode 100644 drivers/virt/bao/io-dispatcher/dm.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/driver.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/intc.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/io_client.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/io_dispatcher.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/ioeventfd.c
>  create mode 100644 drivers/virt/bao/io-dispatcher/irqfd.c
>  create mode 100644 drivers/virt/bao/ipcshmem/Kconfig
>  create mode 100644 drivers/virt/bao/ipcshmem/Makefile
>  create mode 100644 drivers/virt/bao/ipcshmem/ipcshmem.c
>  create mode 100644 include/linux/bao.h
>  create mode 100644 include/uapi/linux/bao.h
> 
> -- 
> 2.43.0
> 

Hi,

This is the friendly patch-bot of Greg Kroah-Hartman.  You have sent him
a patch that has triggered this response.  He used to manually respond
to these common problems, but in order to save his sanity (he kept
writing the same thing over and over, yet to different people), I was
created.  Hopefully you will not take offence and will fix the problem
in your patch and resubmit it so that it can be accepted into the Linux
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You are receiving this message because of the following common error(s)
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- This looks like a new version of a previously submitted patch, but you
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