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{
    "id": 2231622,
    "url": "http://patchwork.ozlabs.org/api/covers/2231622/?format=api",
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        "id": 28,
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        "name": "Linux PCI development",
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    "msgid": "<20260501004157.3108202-1-mrathor@linux.microsoft.com>",
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    "date": "2026-05-01T00:41:46",
    "name": "[V2,00/11] PCI passthru on Hyper-V (Part I)",
    "submitter": {
        "id": 91512,
        "url": "http://patchwork.ozlabs.org/api/people/91512/?format=api",
        "name": "Mukesh R",
        "email": "mrathor@linux.microsoft.com"
    },
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            "url": "http://patchwork.ozlabs.org/api/series/502410/?format=api",
            "web_url": "http://patchwork.ozlabs.org/project/linux-pci/list/?series=502410",
            "date": "2026-05-01T00:41:46",
            "name": "PCI passthru on Hyper-V (Part I)",
            "version": 2,
            "mbox": "http://patchwork.ozlabs.org/series/502410/mbox/"
        }
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        "From": "Mukesh R <mrathor@linux.microsoft.com>",
        "To": "hpa@zytor.com,\n\trobin.murphy@arm.com,\n\trobh@kernel.org,\n\twei.liu@kernel.org,\n\tmrathor@linux.microsoft.com,\n\tmhklinux@outlook.com,\n\tmuislam@microsoft.com,\n\tnamjain@linux.microsoft.com,\n\tmagnuskulke@linux.microsoft.com,\n\tanbelski@linux.microsoft.com,\n\tlinux-kernel@vger.kernel.org,\n\tlinux-hyperv@vger.kernel.org,\n\tiommu@lists.linux.dev,\n\tlinux-pci@vger.kernel.org,\n\tlinux-arch@vger.kernel.org",
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        "Subject": "[PATCH V2 00/11]  PCI passthru on Hyper-V (Part I)",
        "Date": "Thu, 30 Apr 2026 17:41:46 -0700",
        "Message-ID": "<20260501004157.3108202-1-mrathor@linux.microsoft.com>",
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        "MIME-Version": "1.0",
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    },
    "content": "Implement passthru of PCI devices to unprivileged virtual machines\n(VMs) when Linux is running as a privileged VM on Microsoft Hyper-V\nhypervisor. This support is made to fit within the workings of VFIO\nframework, and any VMM needing to use it must use the VFIO subsystem.\nThis supports both full device passthru and SR-IOV based VFs.\n\nAt a high level, the hypervisor supports traditional mapped iommu domains\nthat use explicit map and unmap hypercalls for mapping and unmapping guest\nRAM into the iommu subsystem. Hyper-V also has a concept of direct attach\ndevices whereby the iommu subsystem simply uses the guest HW page table\n(ept/npt/..). This series adds support for both, and both are made to\nwork with the VFIO subsystem.\n\nWhile this Part I focuses on memory mappings, Part II focuses on irq \nremapping and irq migrations.\n\nThis series rebased to: 5170a82e8921 (origin/hyperv-next)\n\nTesting:\n o Most testing done on hyperv-next:e733a9e28180 using Cloud Hypervisor (51).\n o Limited testing on : 5170a82e8921\n o Tested with impending Part II irq patches.\n o All tests involved PF passthru of devices using MSIx.\n o Following combinations were tested:\n    - L1VH(1): test 1: Mellanox ConnectX-6 Lx passthru\n               test 2: NVIDIA Tesla Tesla T4 GPU.\n               test 3: Both of above simultaneous passthru\n    - Baremetal dom0/root: All of above.\n\n(1) L1VH: this is a semi privileged VM that runs on Windows root on\n          Hyper-V, and allows users to create more child VMs.\n\nThis series strives to establish a base line. Some pending work items:\n o arm64 : some delta to make this work on arm64 (in progress).\n o Qemu and OpenVMM support (in progress).\n o VF testing\n o device sleep/wakeup.\n o More stress testing with high end GPUs\n\nChanges in V2:\n o rebase to 5170a82e8921\n o minor fixes for arm64 build\n o drop patch 03: \"x86/hyperv: add insufficient memory support in irqdomain.c\" \n     as it that path is no longer used\n o drop patch 08: \"PCI: hv: rename hv_compose_msi_msg .. \" and do it separately\n   outside this series.\n o minor updates to commit messages\n\nChanges in V1:\n o patch 1: Don't tie hyperv-irq.c to CONFIG_HYPERV_IOMMU.\n o patch 4: Redesigned to address security vulnerability found by copilot \n            with passing tgid as a parameter.  Also, do tgid setting right \n            after setting pt_id.\n o patch 5: Remove unused type parameter from mshv_device_ops.device_create\n o patch 7: mshv_partition_ioctl_create_device cleanup on copy_to_user.\n o patch 10: Add export of hv_build_devid_type_pci here to get rid of \n             patch 11.\n o patch 12: Move functions to build device ids from patch 11 here for\n             the benefit of arm64. Rename file to: hyperv-iommu-root.c.\n o patch 13: removed to be made part of interrupt part II of this support.\n o patch 14: get rid of fast path to reduce review noise.\n o New (last) patch to pin ram regions if device passthru to a VM.\n\nThanks,\n-Mukesh\n\nMukesh R (11):\n  iommu/hyperv: rename hyperv-iommu.c to hyperv-irq.c\n  x86/hyperv: cosmetic changes in irqdomain.c for readability\n  mshv: Provide a way to get partition id if running in a VMM process\n  mshv: Declarations and definitions for VFIO-MSHV bridge device\n  mshv: Implement mshv bridge device for VFIO\n  mshv: Add ioctl support for MSHV-VFIO bridge device\n  mshv: Import data structs around device passthru from hyperv headers\n  PCI: hv: Build device id for a VMBus device, export PCI devid function\n  x86/hyperv: Implement hyperv virtual IOMMU\n  mshv: Populate mmio mappings for PCI passthru\n  mshv: Mark mem regions as non-movable upfront if device passthru\n\n MAINTAINERS                                   |   3 +-\n arch/x86/hyperv/irqdomain.c                   | 199 ++--\n arch/x86/include/asm/mshyperv.h               |   6 +\n arch/x86/kernel/pci-dma.c                     |   2 +\n drivers/hv/Makefile                           |   3 +-\n drivers/hv/mshv_root.h                        |  21 +\n drivers/hv/mshv_root_main.c                   | 266 ++++-\n drivers/hv/mshv_vfio.c                        | 211 ++++\n drivers/iommu/Kconfig                         |   5 +-\n drivers/iommu/Makefile                        |   3 +-\n drivers/iommu/hyperv-iommu-root.c             | 908 ++++++++++++++++++\n .../iommu/{hyperv-iommu.c => hyperv-irq.c}    |   6 +-\n drivers/iommu/irq_remapping.c                 |   2 +-\n drivers/pci/controller/pci-hyperv.c           |  24 +\n include/asm-generic/mshyperv.h                |  30 +\n include/hyperv/hvgdk_mini.h                   |  11 +\n include/hyperv/hvhdk_mini.h                   | 112 +++\n include/linux/hyperv.h                        |   6 +\n include/uapi/linux/mshv.h                     |  31 +\n 19 files changed, 1727 insertions(+), 122 deletions(-)\n create mode 100644 drivers/hv/mshv_vfio.c\n create mode 100644 drivers/iommu/hyperv-iommu-root.c\n rename drivers/iommu/{hyperv-iommu.c => hyperv-irq.c} (99%)"
}