Re: [RFC v16 0/9] SMMUv3 Nested Stage Setup (IOMMU part)

[Zhangfei Gao]

Hi, Eric

On 2021/10/27 下午6:44, Eric Auger wrote:
> This series brings the IOMMU part of HW nested paging support
> in the SMMUv3.
>
> The SMMUv3 driver is adapted to support 2 nested stages.
>
> The IOMMU API is extended to convey the guest stage 1
> configuration and the hook is implemented in the SMMUv3 driver.
>
> This allows the guest to own the stage 1 tables and context
> descriptors (so-called PASID table) while the host owns the
> stage 2 tables and main configuration structures (STE).
>
> This work mainly is provided for test purpose as the upper
> layer integration is under rework and bound to be based on
> /dev/iommu instead of VFIO tunneling. In this version we also get
> rid of the MSI BINDING ioctl, assuming the guest enforces
> flat mapping of host IOVAs used to bind physical MSI doorbells.
> In the current QEMU integration this is achieved by exposing
> RMRs to the guest, using Shameer's series [1]. This approach
> is RFC as the IORT spec is not really meant to do that
> (single mapping flag limitation).
>
> Best Regards
>
> Eric
>
> This series (Host) can be found at:
> https://github.com/eauger/linux/tree/v5.15-rc7-nested-v16
> This includes a rebased VFIO integration (although not meant
> to be upstreamed)
>
> Guest kernel branch can be found at:
> https://github.com/eauger/linux/tree/shameer_rmrr_v7
> featuring [1]
>
> QEMU integration (still based on VFIO and exposing RMRs)
> can be found at:
> https://github.com/eauger/qemu/tree/v6.1.0-rmr-v2-nested_smmuv3_v10
> (use iommu=nested-smmuv3 ARM virt option)
>
> Guest dependency:
> [1] [PATCH v7 0/9] ACPI/IORT: Support for IORT RMR node

Thanks a lot for upgrading these patches.

I have basically verified these patches on HiSilicon Kunpeng920.
And integrated them to these branches.
https://github.com/Linaro/linux-kernel-uadk/tree/uacce-devel-5.16
https://github.com/Linaro/qemu/tree/v6.1.0-rmr-v2-nested_smmuv3_v10

Though they are provided for test purpose,

Tested-by: Zhangfei Gao <zhangfei.gao@xxxxxxxxxx>

Thanks