Hello, This series can be found on Github:
https://github.com/shvipin/linux vfio/liveupdate/v5 This series provides the base support to enable Live Update feature for VFIO PCI devices using the Live Update Orchestrator (LUO) and Kexec Handover (KHO). Overview -------- This series makes the following changes to support VFIO Live Update: - Puts VFIO Live Update support behind the CONFIG_VFIO_PCI_LIVEUPDATE config option (which requires CONFIG_VFIO_DEVICE_CDEV). - Preserves VFIO cdev device FDs across a kexec Live Update session via LUO/KHO. - Enforces that incoming preserved devices can only be retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD post-kexec (preventing legacy group/cdev opens from accessing uninitialized state). - Quiesces the device prior to kexec in freeze() by resetting hardware, disabling bus mastering, and marking the device frozen to reject post-freeze IO/MMIO. - Includes VFIO selftests (uapi & kexec tests with continuous DMA checks) and kernel documentation. VFIO PCI Live Update Roadmap ---------------------------- We are planning to add VFIO PCI Live Update support in phases. Since full support of this feature will come in phase, VFIO PCI Liveupdate is controlled by CONFIG_VFIO_PCI_LIVEUPDATE config option. This series is phase 1 below: 1. PCIe function (non-VF) preserved across Live Update without changing BDF 2. PCIe function (non-VF) preserved across Live Update without resetting 3. PCIe function (non-VF) preserved across Live Update with continuous DMA (noiommu) 4. PCIe function (non-VF) preserved across Live Update with continuous DMA (iommufd) 5. PCIe VF preserved across Live Update with continuous DMA (iommufd) Dependencies ------------ This series has following dependencies as shown in the diagram |---------------------------| | VFIO v5 | <--- Sent in this series. |---------------------------| | Liveupdate Selftests[1] | |---------------------------| | PCI v7 [2] | |---------------------------| [1] https://lore.kernel.org/all/[email protected]/ These selftests changes are needed by other selftests also (iommu, kvm), so, I have sent them separately. [2] https://lore.kernel.org/linux-pci/[email protected]/ This is the PCI v7, which adds the live update support in PCI core. Github branch I have mentioned at the top has all of these dependencies. Testing ------- Tested using VFIO Live Update selftests in both QEMU and bare-metal environment (Intel DSA PCIe device). $ ./setup.sh 0000:00:04.0 $ ./vfio_pci_liveupdate_kexec_test --stage 1 0000:6a:01.0 $ kexec --reuse-cmdline -l -s /boot/vmlinuz $ kexec -e $ ./setup.sh 0000:00:04.0 $ ./vfio_pci_liveupdate_kexec_test --stage 2 0000:6a:01.0 Kernel command line options used: - liveupdate=on - kho=on - vfio_iommu_type1.allow_unsafe_interrupts=Y - vfio_pci.enable_sriov=Y - vfio_pci.disable_denylist=Y - vfio.enable_unsafe_noiommu_mode=Y Changelog --------- v5: - Addressed Sashiko feedback. - Removed condition to disable CONFIG_VFIO_PCI_DMABUF. - Expanded vfio_find_device() helper to safely discover a registered vfio_device by matching criteria. Internal Sashiko instance found data race. - Updated selftests to latest changes in VFIO selftests. - Rebased on top of PCI Live Update series v7. v4: https://lore.kernel.org/kvm/[email protected]/ v3: https://lore.kernel.org/kvm/[email protected]/ v2: https://lore.kernel.org/kvm/[email protected]/ v1: https://lore.kernel.org/kvm/[email protected]/ rfc: https://lore.kernel.org/kvm/[email protected]/ David Matlack (7): vfio: Enforce preserved devices are retrieved via LIVEUPDATE_SESSION_RETRIEVE_FD docs: liveupdate: Add documentation for VFIO PCI vfio: selftests: Add vfio_pci_liveupdate_uapi_test vfio: selftests: Add Makefile support for TEST_GEN_PROGS_EXTENDED vfio: selftests: Expose iommu_modes to tests vfio: selftests: Verify that opening VFIO device fails during Live Update vfio: selftests: Add continuous DMA to vfio_pci_liveupdate_kexec_test Vipin Sharma (13): vfio/pci: Factor out the reset logic in VFIO PCI device close path vfio: Export various helpers from VFIO vfio/pci: Export vfio_pci_dma_buf_move for vfio-pci module liveupdate: Export symbols needed by modules vfio/pci: Register a file handler with Live Update Orchestrator vfio/pci: Preserve vfio-pci device files across Live Update vfio: Introduce vfio_find_device() helper vfio: Refactor vfio_device_fops_cdev_open() vfio: Add API to open cdev device for Live Update restore vfio/pci: Retrieve preserved device files after Live Update vfio: selftests: Build liveupdate library in VFIO selftests vfio: selftests: Initialize vfio_pci_device using a VFIO cdev FD vfio: selftests: Add vfio_pci_liveupdate_kexec_test Documentation/core-api/liveupdate.rst | 1 + .../driver-api/vfio_pci_liveupdate.rst | 23 ++ MAINTAINERS | 2 + drivers/vfio/device_cdev.c | 67 +++- drivers/vfio/group.c | 9 + drivers/vfio/pci/Kconfig | 12 + drivers/vfio/pci/Makefile | 1 + drivers/vfio/pci/vfio_pci.c | 13 +- drivers/vfio/pci/vfio_pci_config.c | 3 + drivers/vfio/pci/vfio_pci_core.c | 119 +++--- drivers/vfio/pci/vfio_pci_dmabuf.c | 1 + drivers/vfio/pci/vfio_pci_liveupdate.c | 340 ++++++++++++++++++ drivers/vfio/pci/vfio_pci_priv.h | 28 ++ drivers/vfio/vfio.h | 18 + drivers/vfio/vfio_main.c | 67 +++- include/linux/kho/abi/vfio_pci.h | 43 +++ include/linux/vfio.h | 12 + include/linux/vfio_pci_core.h | 3 + kernel/liveupdate/luo_file.c | 2 + tools/testing/selftests/vfio/Makefile | 23 +- .../vfio/lib/include/libvfio/iommu.h | 2 + .../lib/include/libvfio/vfio_pci_device.h | 3 + tools/testing/selftests/vfio/lib/iommu.c | 4 +- .../selftests/vfio/lib/vfio_pci_device.c | 25 +- .../vfio/vfio_pci_liveupdate_kexec_test.c | 256 +++++++++++++ .../vfio/vfio_pci_liveupdate_uapi_test.c | 97 +++++ 26 files changed, 1097 insertions(+), 77 deletions(-) create mode 100644 Documentation/driver-api/vfio_pci_liveupdate.rst create mode 100644 drivers/vfio/pci/vfio_pci_liveupdate.c create mode 100644 include/linux/kho/abi/vfio_pci.h create mode 100644 tools/testing/selftests/vfio/vfio_pci_liveupdate_kexec_test.c create mode 100644 tools/testing/selftests/vfio/vfio_pci_liveupdate_uapi_test.c base-commit: cbf37fff757e87376e80e11a8378393a8f25145f prerequisite-patch-id: 85705fb54d3065efe1d87ab4b69e828a9f3404e7 prerequisite-patch-id: a33ae79b5fc0259bd013b430c18cc3d14a678599 -- 2.55.0.795.g602f6c329a-goog
