kernel/linux.git/drivers/vfio/pci, branch v7.1

vfio/pci: Check BAR resources before exporting a DMABUF

2026-05-14T17:39:03+00:00

A DMABUF exports access to BAR resources and, although they are requested at startup time, we need to ensure they really were reserved before exporting. Otherwise, it's possible to access unreserved resources through the export. Add a check to the DMABUF-creation path. Fixes: 5d74781ebc86c ("vfio/pci: Add dma-buf export support for MMIO regions") Signed-off-by: Matt Evans Link: https://lore.kernel.org/r/20260511145829.2993601-3-mattev@meta.com Signed-off-by: Alex Williamson

vfio/pci: Set up BAR resources and maps in vfio_pci_core_enable()

2026-05-14T17:38:04+00:00

Previously BAR resource requests and the corresponding pci_iomap() were performed on-demand and without synchronisation, which was racy. Rather than add synchronisation, it's simplest to address this by doing both activities from vfio_pci_core_enable(). The resource allocation and/or pci_iomap() can still fail; their status is tracked and existing calls to vfio_pci_core_setup_barmap() will fail in a similar way to before. This keeps the point of failure as observed by userspace the same, i.e. failures to request/map unused BARs are benign. Fixes: 89e1f7d4c66d ("vfio: Add PCI device driver") Signed-off-by: Matt Evans Link: https://lore.kernel.org/r/20260511145829.2993601-2-mattev@meta.com [ERR_PTR -> IOMEM_ERR_PTR per lkp report] Signed-off-by: Alex Williamson

vfio/pci: fix dma-buf kref underflow after revoke

2026-05-13T19:58:27+00:00

vfio_pci_dma_buf_move(revoked=true) and vfio_pci_dma_buf_cleanup() ran the same drain sequence: set priv->revoked, invalidate mappings, wait for fences, drop the registered kref, wait for completion. When the VFIO device fd was closed after PCI_COMMAND_MEMORY had been cleared, both ran in turn -- the second kref_put underflowed and the subsequent wait_for_completion() blocked on a completion that the first run had already consumed: refcount_t: underflow; use-after-free. WARNING: lib/refcount.c:28 at refcount_warn_saturate+0x59/0x90 Call Trace: vfio_pci_dma_buf_cleanup+0x163/0x168 [vfio_pci_core] vfio_pci_core_close_device+0x67/0xe0 [vfio_pci_core] vfio_df_close+0x4c/0x80 [vfio] vfio_df_group_close+0x36/0x80 [vfio] vfio_device_fops_release+0x21/0x40 [vfio] __fput+0xe6/0x2b0 __x64_sys_close+0x3d/0x80 Collapse the duplication: vfio_pci_dma_buf_cleanup() now delegates the drain to vfio_pci_dma_buf_move(true), which is idempotent for already-revoked dma-bufs. cleanup retains only list removal and the device registration drop; the dma_resv_lock that bracketed those is dropped along with the in-line drain that required it, memory_lock continues to protect them. Re-arm the kref and the completion at the end of move()'s revoke branch so post-revoke state matches post-creation (kref == 1, completion ready). This keeps cleanup's call into move() a no-op when revoke already ran, and replaces the explicit kref_init() that the un-revoke branch used to perform for the un-revoke -> remap path. Fixes: 1a8a5227f229 ("vfio: Wait for dma-buf invalidation to complete") Reported-by: Joonas Kylmälä Closes: https://lore.kernel.org/all/GVXPR02MB12019AA6014F27EF5D773E89BFB372@GVXPR02MB12019.eurprd02.prod.outlook.com/ Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-7 Reviewed-by: Leon Romanovsky Signed-off-by: Alex Williamson Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Link: https://lore.kernel.org/r/20260507143548.1018405-1-alex.williamson@nvidia.com Signed-off-by: Alex Williamson

vfio/virtio: Use guard() for bar_mutex in legacy I/O

2026-04-21T18:01:21+00:00

Convert the bar_mutex acquisition in virtiovf_issue_legacy_rw_cmd() to use guard(), eliminating the out label and goto-based error paths in favor of direct returns. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Alex Williamson Reviewed-by: Yishai Hadas Link: https://lore.kernel.org/r/20260414200625.3601509-5-alex.williamson@nvidia.com Signed-off-by: Alex Williamson

vfio/virtio: Use guard() for migf->lock where applicable

2026-04-21T18:01:21+00:00

Convert migf->lock acquisitions in virtiovf_disable_fd() and virtiovf_save_read() to use guard(). In virtiovf_save_read() this eliminates the out_unlock label and multiple goto paths by allowing direct returns, and removes the need for the done variable to double as an error carrier. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Alex Williamson Reviewed-by: Yishai Hadas Link: https://lore.kernel.org/r/20260414200625.3601509-4-alex.williamson@nvidia.com Signed-off-by: Alex Williamson

vfio/virtio: Use guard() for list_lock where applicable

2026-04-21T18:01:20+00:00

Convert list_lock mutex acquisitions to use guard() and scoped_guard() where the lock scope aligns with the function or block scope. This simplifies virtiovf_get_data_buff_from_pos() by replacing goto-based unwinding with direct returns. Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Alex Williamson Reviewed-by: Yishai Hadas Link: https://lore.kernel.org/r/20260414200625.3601509-3-alex.williamson@nvidia.com Signed-off-by: Alex Williamson

vfio/virtio: Convert list_lock from spinlock to mutex

2026-04-21T18:01:20+00:00

The list_lock spinlock with IRQ disabling was copied from the mlx5 vfio-pci variant driver, where it is justified by a hardirq async command completion callback that accesses the protected lists. The virtio driver has no such interrupt context usage; all list_lock acquisitions occur in process context via file read/write operations or state transitions under state_mutex. Convert list_lock to a mutex to be consistent with peer vfio-pci variant drivers (hisilicon, pds, qat, xe) which all use mutexes for equivalent migration data protection. This also fixes a mismatched spin_lock()/spin_unlock_irq() pair in virtiovf_read_device_context_chunk() that could incorrectly enable interrupts. Reported-by: Jinhui Guo Closes: https://lore.kernel.org/all/20260413073603.30538-1-guojinhui.liam@bytedance.com Fixes: 0bbc82e4ec79 ("vfio/virtio: Add support for the basic live migration functionality") Cc: stable@vger.kernel.org Assisted-by: Claude:claude-opus-4-6 Signed-off-by: Alex Williamson Reviewed-by: Yishai Hadas Link: https://lore.kernel.org/r/20260414200625.3601509-2-alex.williamson@nvidia.com Signed-off-by: Alex Williamson

vfio/pci: Clean up DMABUFs before disabling function

2026-04-21T18:01:20+00:00

On device shutdown, make vfio_pci_core_close_device() call vfio_pci_dma_buf_cleanup() before the function is disabled via vfio_pci_core_disable(). This ensures that all access via DMABUFs is revoked before the function's BARs become inaccessible. This fixes an issue where, if the function is disabled first, a tiny window exists in which the function's MSE is cleared and yet BARs could still be accessed via the DMABUF. The resources would also be freed and up for grabs by a different driver. Fixes: 5d74781ebc86c ("vfio/pci: Add dma-buf export support for MMIO regions") Signed-off-by: Matt Evans Reviewed-by: Jason Gunthorpe Reviewed-by: Kevin Tian Reviewed-by: Leon Romanovsky Link: https://lore.kernel.org/r/20260415181752.1027604-1-mattev@meta.com Signed-off-by: Alex Williamson

Merge tag 'vfio-v7.1-rc1' of https://github.com/awilliam/linux-vfio

2026-04-16T15:01:16+00:00

Pull VFIO updates from Alex Williamson: - Update QAT vfio-pci variant driver for Gen 5, 420xx devices (Vijay Sundar Selvamani, Suman Kumar Chakraborty, Giovanni Cabiddu) - Fix vfio selftest MMIO DMA mapping selftest (Alex Mastro) - Conversions to const struct class in support of class_create() deprecation (Jori Koolstra) - Improve selftest compiler compatibility by avoiding initializer on variable-length array (Manish Honap) - Define new uAPI for drivers supporting migration to advise user- space of new initial data for reducing target startup latency. Implemented for mlx5 vfio-pci variant driver (Yishai Hadas) - Enable vfio selftests on aarch64, not just cross-compiles reporting arm64 (Ted Logan) - Update vfio selftest driver support to include additional DSA devices (Yi Lai) - Unconditionally include debugfs root pointer in vfio device struct, avoiding a build failure seen in hisi_acc variant driver without debugfs otherwise (Arnd Bergmann) - Add support for the s390 ISM (Internal Shared Memory) device via a new variant driver. The device is unique in the size of its BAR space (256TiB) and lack of mmap support (Julian Ruess) - Enforce that vfio-pci drivers implement a name in their ops structure for use in sequestering SR-IOV VFs (Alex Williamson) - Prune leftover group notifier code (Paolo Bonzini) - Fix Xe vfio-pci variant driver to avoid migration support as a dependency in the reset path and missing release call (Michał Winiarski) * tag 'vfio-v7.1-rc1' of https://github.com/awilliam/linux-vfio: (23 commits) vfio/xe: Add a missing vfio_pci_core_release_dev() vfio/xe: Reorganize the init to decouple migration from reset vfio: remove dead notifier code vfio/pci: Require vfio_device_ops.name MAINTAINERS: add VFIO ISM PCI DRIVER section vfio/ism: Implement vfio_pci driver for ISM devices vfio/pci: Rename vfio_config_do_rw() to vfio_pci_config_rw_single() and export it vfio: unhide vdev->debug_root vfio/qat: add support for Intel QAT 420xx VFs vfio: selftests: Support DMR and GNR-D DSA devices vfio: selftests: Build tests on aarch64 vfio/mlx5: Add REINIT support to VFIO_MIG_GET_PRECOPY_INFO vfio/mlx5: consider inflight SAVE during PRE_COPY net/mlx5: Add IFC bits for migration state vfio: Adapt drivers to use the core helper vfio_check_precopy_ioctl vfio: Add support for VFIO_DEVICE_FEATURE_MIG_PRECOPY_INFOv2 vfio: Define uAPI for re-init initial bytes during the PRE_COPY phase vfio: selftests: Fix VLA initialisation in vfio_pci_irq_set() vfio: uapi: fix comment typo vfio: mdev: replace mtty_dev->vd_class with a const struct class ...

Merge tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel

2026-04-15T15:45:00+00:00

Pull drm updates from Dave Airlie: "Highlights: - new DRM RAS infrastructure using netlink - amdgpu: enable DC on CIK APUs, and more IP enablement, and more user queue work - xe: purgeable BO support, and new hw enablement - dma-buf : add revocable operations Full summary: mm: - two-pass MMU interval notifiers - add gpu active/reclaim per-node stat counters math: - provide __KERNEL_DIV_ROUND_CLOSEST() in UAPI - implement DIV_ROUND_CLOSEST() with __KERNEL_DIV_ROUND_CLOSEST() rust: - shared tag with driver-core: register macro and io infra - core: rework DMA coherent API - core: add interop::list to interop with C linked lists - core: add more num::Bounded operations - core: enable generic_arg_infer and add EMSGSIZE - workqueue: add ARef support for work and delayed work - add GPU buddy allocator abstraction - add DRM shmem GEM helper abstraction - allow drm:::Device to dispatch work and delayed work items to driver private data - add dma_resv_lock helper and raw accessors core: - introduce DRM RAS infrastructure over netlink - add connector panel_type property - fourcc: add ARM interleaved 64k modifier - colorop: add destroy helper - suballoc: split into alloc and init helpers - mode: provide DRM_ARGB_GET*() macros for reading color components edid: - provide drm_output_color_Format dma-buf: - provide revoke mechanism for shared buffers - rename move_notify to invalidate_mappings - always enable move_notify - protect dma_fence_ops with RCU and improve locking - clean pages with helpers atomic: - allocate drm_private_state via callback - helper: use system_percpu_wq buddy: - make buddy allocator available to gpu level - add kernel-doc for buddy allocator - improve aligned allocation ttm: - fix fence signalling - improve tests and docs - improve handling of gfp_retry_mayfail - use per-node stat counters to track memory allocations - port pool to use list_lru - drop NUMA specific pools - make pool shrinker numa aware - track allocated pages per numa node coreboot: - cleanup coreboot framebuffer support sched: - fix race condition in drm_sched_fini pagemap: - enable THP support - pass pagemap_addr by reference gem-shmem: - Track page accessed/dirty status across mmap/vmap gpusvm: - reenable device to device migration - fix unbalanced unclock bridge: - anx7625: Support USB-C plus DT bindings - connector: Fix EDID detection - dw-hdmi-qp: Support Vendor-Specfic and SDP Infoframes; improve others - fsl-ldb: Fix visual artifacts plus related DT property 'enable-termination-resistor' - imx8qxp-pixel-link: Improve bridge reference handling - lt9611: Support Port-B-only input plus DT bindings - tda998x: Support DRM_BRIDGE_ATTACH_NO_CONNECTOR; Clean up - Support TH1520 HDMI plus DT bindings - waveshare-dsi: Fix register and attach; Support 1..4 DSI lanes plus DT bindings - anx7625: Fix USB Type-C handling - cdns-mhdp8546-core: Handle HDCP state in bridge atomic_check - Support Lontium LT8713SX DP MST bridge plus DT bindings - analogix_dp: Use DP helpers for link training panel: - panel-jdi-lt070me05000: Use mipi-dsi multi functions - panel-edp: Support Add AUO B116XAT04.1 (HW: 1A); Support CMN N116BCL-EAK (C2); Support FriendlyELEC plus DT changes - panel-edp: Fix timings for BOE NV140WUM-N64 - ilitek-ili9882t: Allow GPIO calls to sleep - jadard: Support TAIGUAN XTI05101-01A - lxd: Support LXD M9189A plus DT bindings - mantix: Fix pixel clock; Clean up - motorola: Support Motorola Atrix 4G and Droid X2 plus DT bindings - novatek: Support Novatek/Tianma NT37700F plus DT bindings - simple: Support EDT ET057023UDBA plus DT bindings; Support Powertip PH800480T032-ZHC19 plus DT bindings; Support Waveshare 13.3" - novatek-nt36672a: Use mipi_dsi_*_multi() functions - panel-edp: Support BOE NV153WUM-N42, CMN N153JCA-ELK, CSW MNF307QS3-2 - support Himax HX83121A plus DT bindings - support JuTouch JT070TM041 plus DT bindings - support Samsung S6E8FC0 plus DT bindings - himax-hx83102c: support Samsung S6E8FC0 plus DT bindings; support backlight - ili9806e: support Rocktech RK050HR345-CT106A plus DT bindings - simple: support Tianma TM050RDH03 plus DT bindings amdgpu: - enable DC by default on CIK APUs - userq fence ioctl param size fixes - set panel_type to OLED for eDP - refactor DC i2c code - FAMS2 update - rework ttm handling to allow multiple engines - DC DCE 6.x cleanup - DC support for NUTMEG/TRAVIS DP bridge - DCN 4.2 support - GC12 idle power fix for compute - use struct drm_edid in non-DC code - enable NV12/P010 support on primary planes - support newer IP discovery tables - VCN/JPEG 5.0.2 support - GC/MES 12.1 updates - USERQ fixes - add DC idle state manager - eDP DSC seamless boot amdkfd: - GC 12.1 updates - non 4K page fixes xe: - basic Xe3p_LPG and NVL-P enabling patches - allow VM_BIND decompress support - add purgeable buffer object support - add xe_vm_get_property_ioctl - restrict multi-lrc to VCS/VECS engines - allow disabling VM overcommit in fault mode - dGPU memory optimizations - Workaround cleanups and simplification - Allow VFs VRAM quote changes using sysfs - convert GT stats to per-cpu counters - pagefault refactors - enable multi-queue on xe3p_xpc - disable DCC on PTL - make MMIO communication more robust - disable D3Cold for BMG on specific platforms - vfio: improve FLR sync for Xe VFIO i915/display: - C10/C20/LT PHY PLL divider verification - use trans push mechanism to generate PSR frame change on LNL+ - refactor DP DSC slice config - VGA decode refactoring - refactor DPT, gen2-4 overlay, masked field register macro helpers - refactor stolen memory allocation decisions - prepare for UHBR DP tunnels - refactor LT PHY PLL to use DPLL framework - implement register polling/waiting in display code - add shared stepping header between i915 and display i915: - fix potential overflow of shmem scatterlist length nouveau: - provide Z cull info to userspace - initial GA100 support - shutdown on PCI device shutdown nova-core: - harden GSP command queue - add support for large RPCs - simplify GSP sequencer and message handling - refactor falcon firmware handling - convert to new register macro - conver to new DMA coherent API - use checked arithmetic - add debugfs support for gsp-rm log buffers - fix aux device registration for multi-GPU msm: - CI: - Uprev mesa - Restore CI jobs for Qualcomm APQ8016 and APQ8096 devices - Core: - Switched to of_get_available_child_by_name() - DPU: - Fixes for DSC panels - Fixed brownout because of the frequency / OPP mismatch - Quad pipe preparation (not enabled yet) - Switched to virtual planes by default - Dropped VBIF_NRT support - Added support for Eliza platform - Reworked alpha handling - Switched to correct CWB definitions on Eliza - Dropped dummy INTF_0 on MSM8953 - Corrected INTFs related to DP-MST - DP: - Removed debug prints looking into PHY internals - DSI: - Fixes for DSC panels - RGB101010 support - Support for SC8280XP - Moved PHY bindings from display/ to phy/ - GPU: - Preemption support for x2-85 and a840 - IFPC support for a840 - SKU detection support for x2-85 and a840 - Expose AQE support (VK ray-pipeline) - Avoid locking in VM_BIND fence signaling path - Fix to avoid reclaim in GPU snapshot path - Disallow foreign mapping of _NO_SHARE BOs - HDMI: - Fixed infoframes programming - MDP5: - Dropped support for MSM8974v1 - Dropped now unused code for MSM8974 v1 and SDM660 / MSM8998 panthor: - add tracepoints for power and IRQs - fix fence handling - extend timestamp query with flags - support various sources for timestamp queries tyr: - fix names and model/versions rockchip: - vop2: use drm logging function - rk3576 displayport support - support CRTC background color atmel-hlcdc: - support sana5d65 LCD controller tilcdc: - use DT bindings schema - use managed DRM interfaces - support DRM_BRIDGE_ATTACH_NO_CONNECTOR verisilicon: - support DC8200 + DT bindings virtgpu: - support PRIME import with 3D enabled komeda: - fix integer overflow in AFBC checks mcde: - improve bridge handling gma500: - use drm client buffer for fbdev framebuffer amdxdna: - add sensors ioctls - provide NPU power estimate - support column utilization sensor - allow forcing DMA through IOMMU IOVA - support per-BO mem usage queries - refactor GEM implementation ivpu: - update boot API to v3.29.4 - limit per-user number of doorbells/contexts - perform engine reset on TDR error loongson: - replace custom code with drm_gem_ttm_dumb_map_offset() imx: - support planes behind the primary plane - fix bus-format selection vkms: - support CRTC background color v3d: - improve handling of struct v3d_stats komeda: - support Arm China Linlon D6 plus DT bindings imagination: - improve power-off sequence - support context-reset notification from firmware mediatek: - mtk_dsi: enable hs clock during pre-enable - Remove all conflicting aperture devices during probe - Add support for mt8167 display blocks" * tag 'drm-next-2026-04-15' of https://gitlab.freedesktop.org/drm/kernel: (1735 commits) drm/ttm/tests: Remove checks from ttm_pool_free_no_dma_alloc drm/ttm/tests: fix lru_count ASSERT drm/vram: remove DRM_VRAM_MM_FILE_OPERATIONS from docs drm/fb-helper: Fix a locking bug in an error path dma-fence: correct kernel-doc function parameter @flags ttm/pool: track allocated_pages per numa node. ttm/pool: make pool shrinker NUMA aware (v2) ttm/pool: drop numa specific pools ttm/pool: port to list_lru. (v2) drm/ttm: use gpu mm stats to track gpu memory allocations. (v4) mm: add gpu active/reclaim per-node stat counters (v2) gpu: nova-core: fix missing colon in SEC2 boot debug message gpu: nova-core: vbios: use from_le_bytes() for PCI ROM header parsing gpu: nova-core: bitfield: fix broken Default implementation gpu: nova-core: falcon: pad firmware DMA object size to required block alignment gpu: nova-core: gsp: fix undefined behavior in command queue code drm/shmem_helper: Make sure PMD entries get the writeable upgrade accel/ivpu: Trigger recovery on TDR with OS scheduling drm/msm: Use of_get_available_child_by_name() dt-bindings: display/msm: move DSI PHY bindings to phy/ subdir ...