From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from linux.microsoft.com (linux.microsoft.com [13.77.154.182]) by smtp.subspace.kernel.org (Postfix) with ESMTP id F1D50248F66; Fri, 1 May 2026 00:42:07 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=13.77.154.182 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777596129; cv=none; b=h76gq+qj2dvGxTb6jfgv0OHBnUXhnOW/dv9KKcI4HQ1LSJFjWHUGoj0DBJqQB69zetlABzsVAyIiznq/pv097EXRtWvn1icRjW0V6V4VSdiGQWGs6JXIcrUV2LiFqp+85SH095GtPf2TDwXfynO09wOE98L613bw8QwtRUzAu0s= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1777596129; c=relaxed/simple; bh=HgczbydWMyKMmyI8k4BSu6vP0cO81ZFeNwpOwluA5r8=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=RNi5HfwBxfPQaA+Myi+6mQyVUvEgm8OF1HzLH4MAbejyNxFDHQumpKgNuFiGrQq6gcEL+hmIZmFnshoSk+wwjG9GN3IPVWYCvT1mCkSRLtBqpm0YFekx6Ts1BMl6lrCAdh2+87ckg7UXLv1s5qDYy1qn/ikpkp0ZnBmBoewGTcY= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com; spf=pass smtp.mailfrom=linux.microsoft.com; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b=Q4d943jk; arc=none smtp.client-ip=13.77.154.182 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.microsoft.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.microsoft.com header.i=@linux.microsoft.com header.b="Q4d943jk" Received: from mrdev.corp.microsoft.com (unknown [40.86.183.173]) by linux.microsoft.com (Postfix) with ESMTPSA id D651420B7165; Thu, 30 Apr 2026 17:42:06 -0700 (PDT) DKIM-Filter: OpenDKIM Filter v2.11.0 linux.microsoft.com D651420B7165 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.microsoft.com; s=default; t=1777596127; bh=sobSl1Jx196MsXs3tYpB2WD+rsl04IeCc/J8ABEWGzo=; h=From:To:Cc:Subject:Date:From; b=Q4d943jkkAiqHUL3/pHeB+0zJfi0bz679ZcSuvAPmUOrsucCI9R6LWB6Qci6d05G8 DLUH6nxICAqHUyod4w2j4qebNLE6LvDPgLd2rCd/xqIsB0tjVRhDE5g0WayRS4rFen wqbIJA1rREJEB0tmWQCJaJ44jDch6e4H5OmzpcI4= From: Mukesh R To: hpa@zytor.com, robin.murphy@arm.com, robh@kernel.org, wei.liu@kernel.org, mrathor@linux.microsoft.com, mhklinux@outlook.com, muislam@microsoft.com, namjain@linux.microsoft.com, magnuskulke@linux.microsoft.com, anbelski@linux.microsoft.com, linux-kernel@vger.kernel.org, linux-hyperv@vger.kernel.org, iommu@lists.linux.dev, linux-pci@vger.kernel.org, linux-arch@vger.kernel.org Cc: kys@microsoft.com, haiyangz@microsoft.com, decui@microsoft.com, longli@microsoft.com, tglx@kernel.org, mingo@redhat.com, bp@alien8.de, dave.hansen@linux.intel.com, x86@kernel.org, joro@8bytes.org, will@kernel.org, lpieralisi@kernel.org, kwilczynski@kernel.org, bhelgaas@google.com, arnd@arndb.de 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> X-Mailer: git-send-email 2.51.2.vfs.0.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Implement passthru of PCI devices to unprivileged virtual machines (VMs) when Linux is running as a privileged VM on Microsoft Hyper-V hypervisor. This support is made to fit within the workings of VFIO framework, and any VMM needing to use it must use the VFIO subsystem. This supports both full device passthru and SR-IOV based VFs. At a high level, the hypervisor supports traditional mapped iommu domains that use explicit map and unmap hypercalls for mapping and unmapping guest RAM into the iommu subsystem. Hyper-V also has a concept of direct attach devices whereby the iommu subsystem simply uses the guest HW page table (ept/npt/..). This series adds support for both, and both are made to work with the VFIO subsystem. While this Part I focuses on memory mappings, Part II focuses on irq remapping and irq migrations. This series rebased to: 5170a82e8921 (origin/hyperv-next) Testing: o Most testing done on hyperv-next:e733a9e28180 using Cloud Hypervisor (51). o Limited testing on : 5170a82e8921 o Tested with impending Part II irq patches. o All tests involved PF passthru of devices using MSIx. o Following combinations were tested: - L1VH(1): test 1: Mellanox ConnectX-6 Lx passthru test 2: NVIDIA Tesla Tesla T4 GPU. test 3: Both of above simultaneous passthru - Baremetal dom0/root: All of above. (1) L1VH: this is a semi privileged VM that runs on Windows root on Hyper-V, and allows users to create more child VMs. This series strives to establish a base line. Some pending work items: o arm64 : some delta to make this work on arm64 (in progress). o Qemu and OpenVMM support (in progress). o VF testing o device sleep/wakeup. o More stress testing with high end GPUs Changes in V2: o rebase to 5170a82e8921 o minor fixes for arm64 build o drop patch 03: "x86/hyperv: add insufficient memory support in irqdomain.c" as it that path is no longer used o drop patch 08: "PCI: hv: rename hv_compose_msi_msg .. " and do it separately outside this series. o minor updates to commit messages Changes in V1: o patch 1: Don't tie hyperv-irq.c to CONFIG_HYPERV_IOMMU. o patch 4: Redesigned to address security vulnerability found by copilot with passing tgid as a parameter. Also, do tgid setting right after setting pt_id. o patch 5: Remove unused type parameter from mshv_device_ops.device_create o patch 7: mshv_partition_ioctl_create_device cleanup on copy_to_user. o patch 10: Add export of hv_build_devid_type_pci here to get rid of patch 11. o patch 12: Move functions to build device ids from patch 11 here for the benefit of arm64. Rename file to: hyperv-iommu-root.c. o patch 13: removed to be made part of interrupt part II of this support. o patch 14: get rid of fast path to reduce review noise. o New (last) patch to pin ram regions if device passthru to a VM. Thanks, -Mukesh Mukesh R (11): iommu/hyperv: rename hyperv-iommu.c to hyperv-irq.c x86/hyperv: cosmetic changes in irqdomain.c for readability mshv: Provide a way to get partition id if running in a VMM process mshv: Declarations and definitions for VFIO-MSHV bridge device mshv: Implement mshv bridge device for VFIO mshv: Add ioctl support for MSHV-VFIO bridge device mshv: Import data structs around device passthru from hyperv headers PCI: hv: Build device id for a VMBus device, export PCI devid function x86/hyperv: Implement hyperv virtual IOMMU mshv: Populate mmio mappings for PCI passthru mshv: Mark mem regions as non-movable upfront if device passthru MAINTAINERS | 3 +- arch/x86/hyperv/irqdomain.c | 199 ++-- arch/x86/include/asm/mshyperv.h | 6 + arch/x86/kernel/pci-dma.c | 2 + drivers/hv/Makefile | 3 +- drivers/hv/mshv_root.h | 21 + drivers/hv/mshv_root_main.c | 266 ++++- drivers/hv/mshv_vfio.c | 211 ++++ drivers/iommu/Kconfig | 5 +- drivers/iommu/Makefile | 3 +- drivers/iommu/hyperv-iommu-root.c | 908 ++++++++++++++++++ .../iommu/{hyperv-iommu.c => hyperv-irq.c} | 6 +- drivers/iommu/irq_remapping.c | 2 +- drivers/pci/controller/pci-hyperv.c | 24 + include/asm-generic/mshyperv.h | 30 + include/hyperv/hvgdk_mini.h | 11 + include/hyperv/hvhdk_mini.h | 112 +++ include/linux/hyperv.h | 6 + include/uapi/linux/mshv.h | 31 + 19 files changed, 1727 insertions(+), 122 deletions(-) create mode 100644 drivers/hv/mshv_vfio.c create mode 100644 drivers/iommu/hyperv-iommu-root.c rename drivers/iommu/{hyperv-iommu.c => hyperv-irq.c} (99%) -- 2.51.2.vfs.0.1