Re: [PATCH 00/20] Add SMMUv3 Stage 1 Support for XEN guests

[Julien Grall <julien.grall.oss@xxxxxxxxx>]

Hi Milan,

On Thu, 7 Aug 2025 at 17:55, Milan Djokic <milan_djokic@xxxxxxxx> wrote:

This patch series represents a rebase of an older patch series implemented and
sumbitted by Rahul Singh as an RFC: https://patchwork.kernel.org/project/xen-devel/cover/cover.1669888522.git.rahul.singh@xxxxxxx/.
Original patch series content is aligned with the latest xen structure in terms of common/arch-specific code structuring.
Some minor bugfixes are also applied:
- Sanity checks / error handling
- Non-pci devices support for emulated iommu

Overall description of stage-1 support is available in the original
patch series cover letter. Original commits structure with detailed explanation for each commit
functionality is maintained.

I am a bit surprised not much has changed. Last time we asked a document to explain the overall design of the vSMMU including some details on the security posture. I can’t remember if this was ever posted.

If not, then you need to start with that. Otherwise, if is going to be pretty difficult to review this series.

Cheers,

Patch series testing is performed in qemu arm environment. Additionally,
stage-1 translation for non-pci devices is verified on a Renesas platform.

Jean-Philippe Brucker (1):
  xen/arm: smmuv3: Maintain a SID->device structure

Rahul Singh (19):
  xen/arm: smmuv3: Add support for stage-1 and nested stage translation
  xen/arm: smmuv3: Alloc io_domain for each device
  xen/arm: vIOMMU: add generic vIOMMU framework
  xen/arm: vsmmuv3: Add dummy support for virtual SMMUv3 for guests
  xen/domctl: Add XEN_DOMCTL_CONFIG_VIOMMU_* and viommu config param
  xen/arm: vIOMMU: Add cmdline boot option "viommu = <boolean>"
  xen/arm: vsmmuv3: Add support for registers emulation
  xen/arm: vsmmuv3: Add support for cmdqueue handling
  xen/arm: vsmmuv3: Add support for command CMD_CFGI_STE
  xen/arm: vsmmuv3: Attach Stage-1 configuration to SMMUv3 hardware
  xen/arm: vsmmuv3: Add support for event queue and global error
  xen/arm: vsmmuv3: Add "iommus" property node for dom0 devices
  xen/arm: vIOMMU: IOMMU device tree node for dom0
  xen/arm: vsmmuv3: Emulated SMMUv3 device tree node for dom0less
  arm/libxl: vsmmuv3: Emulated SMMUv3 device tree node in libxl
  xen/arm: vsmmuv3: Alloc virq for virtual SMMUv3
  xen/arm: vsmmuv3: Add support to send stage-1 event to guest
  libxl/arm: vIOMMU: Modify the partial device tree for iommus
  xen/arm: vIOMMU: Modify the partial device tree for dom0less

 docs/man/xl.cfg.5.pod.in                |  13 +
 docs/misc/xen-command-line.pandoc       |   7 +
 tools/golang/xenlight/helpers.gen.go    |   2 +
 tools/golang/xenlight/types.gen.go      |   1 +
 tools/include/libxl.h                   |   5 +
 tools/libs/light/libxl_arm.c            | 123 +++-
 tools/libs/light/libxl_types.idl        |   6 +
 tools/xl/xl_parse.c                     |  10 +
 xen/arch/arm/dom0less-build.c           |  72 ++
 xen/arch/arm/domain.c                   |  26 +
 xen/arch/arm/domain_build.c             | 103 ++-
 xen/arch/arm/include/asm/domain.h       |   4 +
 xen/arch/arm/include/asm/viommu.h       | 102 +++
 xen/common/device-tree/dom0less-build.c |  31 +-
 xen/drivers/passthrough/Kconfig         |  14 +
 xen/drivers/passthrough/arm/Makefile    |   2 +
 xen/drivers/passthrough/arm/smmu-v3.c   | 369 +++++++++-
 xen/drivers/passthrough/arm/smmu-v3.h   |  49 +-
 xen/drivers/passthrough/arm/viommu.c    |  87 +++
 xen/drivers/passthrough/arm/vsmmu-v3.c  | 895 ++++++++++++++++++++++++
 xen/drivers/passthrough/arm/vsmmu-v3.h  |  32 +
 xen/include/public/arch-arm.h           |  14 +-
 xen/include/public/device_tree_defs.h   |   1 +
 xen/include/xen/iommu.h                 |  14 +
 24 files changed, 1935 insertions(+), 47 deletions(-)
 create mode 100644 xen/arch/arm/include/asm/viommu.h
 create mode 100644 xen/drivers/passthrough/arm/viommu.c
 create mode 100644 xen/drivers/passthrough/arm/vsmmu-v3.c
 create mode 100644 xen/drivers/passthrough/arm/vsmmu-v3.h

--
2.43.0