TLDR: The bo->ttm object might be changed by calling ttm_bo_validate(),
      move casting it to an i915_tt object later to actually get the right
      pointer.

A user reported hitting the following bug under heavy use on DG2:

[26620.095550] Oops: general protection fault, probably for non-canonical address 0xa56b6b6b6b6b6b8b: 0000 1 SMP NOPTI
[26620.095556] CPU: 2 UID: 0 PID: 631 Comm: Xorg Not tainted 6.18.8 #1 PREEMPT(lazy)
[26620.095558] Hardware name: ASRock B850M Steel Legend WiFi/B850M Steel Legend WiFi, BIOS 3.50 09/18/2025
[26620.095559] RIP: 0010:i915_ttm_purge+0x84/0x100 [i915]
[26620.095604] Code: 00 00 00 48 8d 54 24 10 48 89 e6 48 89 fb e8 83 aa ae ff 85 c0 75 6f 48 83 bb a8 01 00 00 00 74 2c 48 8b 45 78 48 85 c0 74 23 <48> 8b 78 20 48 c7 c2 ff ff ff ff 31 f6 e8 7a 73 e3 e0 48 8b 7d 78
[26620.095605] RSP: 0018:ffffc90005fd7430 EFLAGS: 00010282
[26620.095607] RAX: a56b6b6b6b6b6b6b RBX: ffff8881f46c3dc0 RCX: 0000000000000000
[26620.095608] RDX: 0000000000000000 RSI: 0000000000000246 RDI: 00000000ffffffff
[26620.095609] RBP: ffff888289610f00 R08: 0000000000000001 R09: ffff88823b022000
[26620.095609] R10: ffff888103029b28 R11: ffff8881fc7f3800 R12: ffff88810b6150d0
[26620.095609] R13: ffff888289610f00 R14: 0000000000000000 R15: ffff8881f46c3dc0
[26620.095610] FS: 00007f1004d86900(0000) GS:ffff88901c858000(0000) knlGS:0000000000000000
[26620.095611] CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[26620.095611] CR2: 00007f0fdf489000 CR3: 000000035b0c1000 CR4: 0000000000750ef0
[26620.095612] PKRU: 55555554
[26620.095612] Call Trace:
[26620.095615] <TASK>
[26620.095615] i915_ttm_move+0x2b9/0x420 [i915]
[26620.095642] ? ttm_tt_init+0x65/0x80 [ttm]
[26620.095644] ? i915_ttm_tt_create+0xc6/0x150 [i915]
[26620.095667] ttm_bo_handle_move_mem+0xb6/0x160 [ttm]
[26620.095669] ttm_bo_evict+0x100/0x150 [ttm]
[26620.095671] ? preempt_count_add+0x64/0xa0
[26620.095673] ? _raw_spin_lock+0xe/0x30
[26620.095675] ? _raw_spin_unlock+0xd/0x30
[26620.095675] ? i915_gem_object_evictable+0xb7/0xd0 [i915]
[26620.095704] ttm_bo_evict_cb+0x6e/0xd0 [ttm]
[26620.095705] ttm_lru_walk_for_evict+0xa6/0x200 [ttm]
[26620.095708] ttm_bo_alloc_resource+0x185/0x4f0 [ttm]
[26620.095709] ? init_object+0x62/0xd0
[26620.095712] ttm_bo_validate+0x7a/0x180 [ttm]
[26620.095713] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095714] __i915_ttm_get_pages+0xb0/0x170 [i915]
[26620.095737] i915_ttm_get_pages+0x9f/0x150 [i915]
[26620.095759] ? i915_gem_do_execbuffer+0xedc/0x2b40 [i915]
[26620.095786] ? alloc_debug_processing+0xd0/0x100
[26620.095787] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095788] ? i915_vma_instance+0xa0/0x4e0 [i915]
[26620.095822] __i915_gem_object_get_pages+0x2f/0x40 [i915]
[26620.095848] i915_vma_pin_ww+0x706/0x980 [i915]
[26620.095875] ? i915_gem_do_execbuffer+0xedc/0x2b40 [i915]
[26620.095904] eb_validate_vmas+0x170/0xa00 [i915]
[26620.095930] i915_gem_do_execbuffer+0x1201/0x2b40 [i915]
[26620.095953] ? alloc_debug_processing+0xd0/0x100
[26620.095954] ? _raw_spin_unlock_irqrestore+0x16/0x30
[26620.095955] ? i915_gem_execbuffer2_ioctl+0xc9/0x240 [i915]
[26620.095977] ? __wake_up_sync_key+0x32/0x50
[26620.095979] ? i915_gem_execbuffer2_ioctl+0xc9/0x240 [i915]
[26620.096001] ? __slab_alloc.isra.0+0x67/0xc0
[26620.096003] i915_gem_execbuffer2_ioctl+0x11a/0x240 [i915]

Results from decode_stacktrace.sh pointed to dereference of a file pointer
field of a i915 TTM page vector container associated with an object being
purged on eviction.  That path is taken when the object is marked as no
longer needed.

Code analysis revealed a possibility of the i915 TTM page vector container
being replaced with a new instance inside a function that purges content
of the object, should it be still busy.  That function is called,
indirectly via a more general function that changes the object's placement
and caching policy, before the problematic dereference, but still after
a pointer to the container is captured, rendering the pointer no longer
valid.

Fix the issue by capturing the pointer to the container only after its
potential replacement.

v2: Move the container_of() inside the if block (Sebastian),
  - a simplified version of the commit description that explains briefly
    why the change is necessary (Christian).

Closes: https://gitlab.freedesktop.org/drm/i915/kernel/-/work_items/14882
Fixes: 7ae034590ceae ("drm/i915/ttm: add tt shmem backend")
Signed-off-by: Janusz Krzysztofik <janusz.krzysztofik@linux.intel.com>
Cc: stable@vger.kernel.org # v5.17+
Cc: Matthew Auld <matthew.auld@intel.com>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Sebastian Brzezinka <sebastian.brzezinka@intel.com>
Cc: Christian König <christian.koenig@amd.com>
Reviewed-by: Andi Shyti <andi.shyti@linux.intel.com>
Reviewed-by: Christian König <christian.koenig@amd.com>
Signed-off-by: Andi Shyti <andi.shyti@linux.intel.com>
Link: https://lore.kernel.org/r/20260508122612.469227-2-janusz.krzysztofik@linux.intel.com
(cherry picked from commit 4462966a93eb185849b7f174f0d0de53476d00a4)
Signed-off-by: Tvrtko Ursulin <tursulin@ursulin.net>

Pull MM updates from Andrew Morton:

 - "maple_tree: Replace big node with maple copy" (Liam Howlett)

   Mainly prepararatory work for ongoing development but it does reduce
   stack usage and is an improvement.

 - "mm, swap: swap table phase III: remove swap_map" (Kairui Song)

   Offers memory savings by removing the static swap_map. It also yields
   some CPU savings and implements several cleanups.

 - "mm: memfd_luo: preserve file seals" (Pratyush Yadav)

   File seal preservation to LUO's memfd code

 - "mm: zswap: add per-memcg stat for incompressible pages" (Jiayuan
   Chen)

   Additional userspace stats reportng to zswap

 - "arch, mm: consolidate empty_zero_page" (Mike Rapoport)

   Some cleanups for our handling of ZERO_PAGE() and zero_pfn

 - "mm/kmemleak: Improve scan_should_stop() implementation" (Zhongqiu
   Han)

   A robustness improvement and some cleanups in the kmemleak code

 - "Improve khugepaged scan logic" (Vernon Yang)

   Improve khugepaged scan logic and reduce CPU consumption by
   prioritizing scanning tasks that access memory frequently

 - "Make KHO Stateless" (Jason Miu)

   Simplify Kexec Handover by transitioning KHO from an xarray-based
   metadata tracking system with serialization to a radix tree data
   structure that can be passed directly to the next kernel

 - "mm: vmscan: add PID and cgroup ID to vmscan tracepoints" (Thomas
   Ballasi and Steven Rostedt)

   Enhance vmscan's tracepointing

 - "mm: arch/shstk: Common shadow stack mapping helper and
   VM_NOHUGEPAGE" (Catalin Marinas)

   Cleanup for the shadow stack code: remove per-arch code in favour of
   a generic implementation

 - "Fix KASAN support for KHO restored vmalloc regions" (Pasha Tatashin)

   Fix a WARN() which can be emitted the KHO restores a vmalloc area

 - "mm: Remove stray references to pagevec" (Tal Zussman)

   Several cleanups, mainly udpating references to "struct pagevec",
   which became folio_batch three years ago

 - "mm: Eliminate fake head pages from vmemmap optimization" (Kiryl
   Shutsemau)

   Simplify the HugeTLB vmemmap optimization (HVO) by changing how tail
   pages encode their relationship to the head page

 - "mm/damon/core: improve DAMOS quota efficiency for core layer
   filters" (SeongJae Park)

   Improve two problematic behaviors of DAMOS that makes it less
   efficient when core layer filters are used

 - "mm/damon: strictly respect min_nr_regions" (SeongJae Park)

   Improve DAMON usability by extending the treatment of the
   min_nr_regions user-settable parameter

 - "mm/page_alloc: pcp locking cleanup" (Vlastimil Babka)

   The proper fix for a previously hotfixed SMP=n issue. Code
   simplifications and cleanups ensued

 - "mm: cleanups around unmapping / zapping" (David Hildenbrand)

   A bunch of cleanups around unmapping and zapping. Mostly
   simplifications, code movements, documentation and renaming of
   zapping functions

 - "support batched checking of the young flag for MGLRU" (Baolin Wang)

   Batched checking of the young flag for MGLRU. It's part cleanups; one
   benchmark shows large performance benefits for arm64

 - "memcg: obj stock and slab stat caching cleanups" (Johannes Weiner)

   memcg cleanup and robustness improvements

 - "Allow order zero pages in page reporting" (Yuvraj Sakshith)

   Enhance free page reporting - it is presently and undesirably order-0
   pages when reporting free memory.

 - "mm: vma flag tweaks" (Lorenzo Stoakes)

   Cleanup work following from the recent conversion of the VMA flags to
   a bitmap

 - "mm/damon: add optional debugging-purpose sanity checks" (SeongJae
   Park)

   Add some more developer-facing debug checks into DAMON core

 - "mm/damon: test and document power-of-2 min_region_sz requirement"
   (SeongJae Park)

   An additional DAMON kunit test and makes some adjustments to the
   addr_unit parameter handling

 - "mm/damon/core: make passed_sample_intervals comparisons
   overflow-safe" (SeongJae Park)

   Fix a hard-to-hit time overflow issue in DAMON core

 - "mm/damon: improve/fixup/update ratio calculation, test and
   documentation" (SeongJae Park)

   A batch of misc/minor improvements and fixups for DAMON

 - "mm: move vma_(kernel|mmu)_pagesize() out of hugetlb.c" (David
   Hildenbrand)

   Fix a possible issue with dax-device when CONFIG_HUGETLB=n. Some code
   movement was required.

 - "zram: recompression cleanups and tweaks" (Sergey Senozhatsky)

   A somewhat random mix of fixups, recompression cleanups and
   improvements in the zram code

 - "mm/damon: support multiple goal-based quota tuning algorithms"
   (SeongJae Park)

   Extend DAMOS quotas goal auto-tuning to support multiple tuning
   algorithms that users can select

 - "mm: thp: reduce unnecessary start_stop_khugepaged()" (Breno Leitao)

   Fix the khugpaged sysfs handling so we no longer spam the logs with
   reams of junk when starting/stopping khugepaged

 - "mm: improve map count checks" (Lorenzo Stoakes)

   Provide some cleanups and slight fixes in the mremap, mmap and vma
   code

 - "mm/damon: support addr_unit on default monitoring targets for
   modules" (SeongJae Park)

   Extend the use of DAMON core's addr_unit tunable

 - "mm: khugepaged cleanups and mTHP prerequisites" (Nico Pache)

   Cleanups to khugepaged and is a base for Nico's planned khugepaged
   mTHP support

 - "mm: memory hot(un)plug and SPARSEMEM cleanups" (David Hildenbrand)

   Code movement and cleanups in the memhotplug and sparsemem code

 - "mm: remove CONFIG_ARCH_ENABLE_MEMORY_HOTREMOVE and cleanup
   CONFIG_MIGRATION" (David Hildenbrand)

   Rationalize some memhotplug Kconfig support

 - "change young flag check functions to return bool" (Baolin Wang)

   Cleanups to change all young flag check functions to return bool

 - "mm/damon/sysfs: fix memory leak and NULL dereference issues" (Josh
   Law and SeongJae Park)

   Fix a few potential DAMON bugs

 - "mm/vma: convert vm_flags_t to vma_flags_t in vma code" (Lorenzo
   Stoakes)

   Convert a lot of the existing use of the legacy vm_flags_t data type
   to the new vma_flags_t type which replaces it. Mainly in the vma
   code.

 - "mm: expand mmap_prepare functionality and usage" (Lorenzo Stoakes)

   Expand the mmap_prepare functionality, which is intended to replace
   the deprecated f_op->mmap hook which has been the source of bugs and
   security issues for some time. Cleanups, documentation, extension of
   mmap_prepare into filesystem drivers

 - "mm/huge_memory: refactor zap_huge_pmd()" (Lorenzo Stoakes)

   Simplify and clean up zap_huge_pmd(). Additional cleanups around
   vm_normal_folio_pmd() and the softleaf functionality are performed.

* tag 'mm-stable-2026-04-13-21-45' of git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm: (369 commits)
  mm: fix deferred split queue races during migration
  mm/khugepaged: fix issue with tracking lock
  mm/huge_memory: add and use has_deposited_pgtable()
  mm/huge_memory: add and use normal_or_softleaf_folio_pmd()
  mm: add softleaf_is_valid_pmd_entry(), pmd_to_softleaf_folio()
  mm/huge_memory: separate out the folio part of zap_huge_pmd()
  mm/huge_memory: use mm instead of tlb->mm
  mm/huge_memory: remove unnecessary sanity checks
  mm/huge_memory: deduplicate zap deposited table call
  mm/huge_memory: remove unnecessary VM_BUG_ON_PAGE()
  mm/huge_memory: add a common exit path to zap_huge_pmd()
  mm/huge_memory: handle buggy PMD entry in zap_huge_pmd()
  mm/huge_memory: have zap_huge_pmd return a boolean, add kdoc
  mm/huge: avoid big else branch in zap_huge_pmd()
  mm/huge_memory: simplify vma_is_specal_huge()
  mm: on remap assert that input range within the proposed VMA
  mm: add mmap_action_map_kernel_pages[_full]()
  uio: replace deprecated mmap hook with mmap_prepare in uio_info
  drivers: hv: vmbus: replace deprecated mmap hook with mmap_prepare
  mm: allow handling of stacked mmap_prepare hooks in more drivers
  ...

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<T> 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
  ...

Since the introduction of d4433c7600f7 ("drm/i915/gem: Use the proto-context
to handle create parameters (v5)") it has not been possible for VM to change
after context creation so the check will never fail.

Sima's analysis:

  This check was added in f7ce8639f6ff ("drm/i915/gem: Split the context's
  obj:vma lut into its own mutex") but without any hint in the commit
  message as to why. In another hunk of that commit there's a hint though in
  __eb_add_lut:

          /* user racing with ctx set-vm */

  This would mean that this bug was introduced in e0695db7298e ("drm/i915:
  Create/destroy VM (ppGTT) for use with contexts"), which allowed to change
  the gem_ctx->vm at runtime, opening up the race that was partially fixed
  in the earlier referenced commit about a year later.

  But it cannot be exploited anymore in anything remotely recent because
  with the introduction of proto-contexts we've made gem_ctx->vm invariant
  again, exactly to preemptively close all these potential issues.
  Specifically d4433c7600f7 ("drm/i915/gem: Use the proto-context to handle
  create parameters (v5)") is the vm specific part of the proto-context
  work.

v3:
- Include Sima's analysis and WARN_ON_ONCE

v4:
- Focus only on latest mainline codebase

References: https://lore.kernel.org/all/20260324151741.29338-1-sosohero200@gmail.com/
Reported-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Cc: Linus Torvalds <torvalds@linuxfoundation.org>
Cc: Simona Vetter <simona.vetter@ffwll.ch>
Cc: Tvrtko Ursulin <tursulin@ursulin.net>
Cc: Andi Shyti <andi.shyti@kernel.org>
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>
Reviewed-by: Tvrtko Ursulin <tvrtko.ursulin@igalia.com>
Link: https://patch.msgid.link/20260409053111.8914-1-joonas.lahtinen@linux.intel.com
(cherry picked from commit f6d4afc9ec6a0bc326151b35a7a3369369180079)
Signed-off-by: Joonas Lahtinen <joonas.lahtinen@linux.intel.com>

Thomas Zimmermann needs 2f42c1a61616 ("drm/ast: dp501: Fix
initialization of SCU2C") for drm-misc-next.

Conflicts:
- drivers/gpu/drm/amd/display/dc/hwss/dcn401/dcn401_hwseq.c

Just between e927b36ae18b ("drm/amd/display: Fix NULL pointer
dereference in dcn401_init_hw()") and it's cherry-pick that confused
git.

- drivers/gpu/drm/amd/pm/swsmu/smu11/smu_v11_0.c

Deleted in 6b0a6116286e ("drm/amd/pm: Unify version check in SMUv11")
but some cherry-picks confused git. Same for v12/v14.

Signed-off-by: Simona Vetter <simona.vetter@ffwll.ch>

struct pagevec was removed in commit 1e0877d58b1e ("mm: remove struct
pagevec").  Rename include/linux/pagevec.h to reflect reality and update
includes tree-wide.  Add the new filename to MAINTAINERS explicitly, as it
no longer matches the "include/linux/page[-_]*" pattern in MEMORY
MANAGEMENT - CORE.

Link: https://lkml.kernel.org/r/20260225-pagevec_cleanup-v2-3-716868cc2d11@columbia.edu
Signed-off-by: Tal Zussman <tz2294@columbia.edu>
Acked-by: David Hildenbrand (Arm) <david@kernel.org>
Reviewed-by: Jan Kara <jack@suse.cz>
Acked-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Lorenzo Stoakes (Oracle) <ljs@kernel.org>
Cc: Chris Li <chrisl@kernel.org>
Cc: Christian Brauner <brauner@kernel.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

In eb_lookup_vma(), the code checks that the context vm matches before
incrementing the i915 vma usage count, but for the non-matching case it
didn't clear the non-matching vma pointer, so it would then mistakenly
be returned, causing potential UaF and refcount issues.

Reported-by: Yassine Mounir <sosohero200@gmail.com>
Suggested-by: Ville Syrjälä <ville.syrjala@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

[airlied: fixed conflict with xe tree]
drm/i915 feature pull for v7.1:

Features and functionality:
- C10/C20/LT PHY PLL divider verification (Mika)
- Use trans push mechanism to generate PSR frame change event on LNL+ (Jouni)
- Account for DSC bubble overhead for horizontal slices (Ankit, Chaitanya)

Refactoring and cleanups:
- Refactor DP DSC slice config computation (Imre)
- Use GVT versions of register helper macros for GVT MMIO table (Ankit)
- C10/C20/LT PHY PLL computation refactoring (Mika)
- VGA decode refactoring and related fixes/cleanups (Ville)
- Move DSB buffer buffer implementation to display parent interface (Jani)
- Move error interrupt capture to display irq snapshot (Jani)
- Move pcode calls to display parent interface (Jani)
- Reduce GVT dependency on display headers (Jani)
- Compute config and mode valid refactoring for DSC (Ankit)
- Stop using i915 core register headers in display (Uma)
- Refactor DPT, move i915 parts to display parent interface (Jani)
- Refactor gen2-4 overlay, move to display parent interface (Ville)
- Refactor masked field register macro helpers, move to shared headers (Jani)
- Convert a number of workaround checks to the new workaround framework (Luca)
- Refactor and move frontbuffer calls to display parent interface (Jani)
- Add VMA calls to display parent interface (Jani)
- Refactor stolen memory allocation decisions (Vinod, Ville)
- Clean up and unify workqueue usage (Marco Crivellari)
- Preparation for UHBR DP tunnels (Imre)
- Allow DSC passthrough modes during DP MST mode validation (Imre)
- Move framebuffer bo interface to display parent interface (Jani)

Fixes:
- Plenty of DP SST HPD IRQ handling fixes (Imre)
- DP AUX backlight and luminance control fixes (Suraj)
- Respect VBT pipe joiner disable for eDP (Ankit)
- Do not use CASF with joiner (Nemesa)
- Clear C10/C20 PHY response read and error bit to avoid PHY hangs (Suraj)
- Xe3p_LPD DMG clock gating, CDCLK, port sync workarounds (Suraj, Gustavo, Mitul)
- Fix GVT error path (Michał)
- Handle errors on DP DSC receiver cap reads (Suraj)
- DSS clock gating workaround on MTL+ to avoid DSC corruption (Mika)
- Skip state verification for LT PHY in TBT mode (Suraj)
- Fix NULL pointer dereference on suspend when uc firmware not loaded (Rahul Bukte)
- Fix an unlikely DMC state related NULL pointer dereference at probe (Imre)
- Handle error returns from vga_get_uninterruptible() (Simon Richter)
- Increase C10/C20/LT PHY timeouts to include SOC/OS turnaround (Arun)
- Fix BIOS FB vs. stolen memory size check (Ville)
- Fix LOBF to use computed guardband and set context latency (Ankit)
- Handle modeset WW mutex lock failures due to contention properly (Imre)
- Fix pipe BPP clamping due to HDR (Imre)
- Fix stale state usage in DSC state computation (Imre)
- Take HDCP 1.4 vs 2.x into account during link check (Suraj)
- Fix forced link retrain handling in MST HPD IRQ handler (Imre)
- Remove redundant warning on vcpi < 0 (Jonathan)

Core changes:
- iopoll: fix function parameter names in read_poll_timeout_atomic() (Randy Dunlap)

Merges:
- Backmerge drm-next for v7.0-rc1 (Jani)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Jani Nikula <jani.nikula@intel.com>
Link: https://patch.msgid.link/b14bb0f297b1750816cf5f342bde608e435655fa@intel.com

Driver Changes:

Fixes/improvements/new stuff:

- Fix potential overflow of shmem scatterlist length (Janusz Krzysztofik)

Miscellaneous:

- Keep mock file open during unfaultable migrate with fill [selftests] (Krzysztof Karas)
- Test for imported buffers with drm_gem_is_imported() (Thomas Zimmermann)
- Fix corrupted copyright symbols in selftest files [guc] (Konstantin Khorenko)

Signed-off-by: Dave Airlie <airlied@redhat.com>
From: Tvrtko Ursulin <tursulin@igalia.com>
Link: https://patch.msgid.link/abKBHNFsBQCv2h3e@linux

Move the get/put/ref/flush_for_display calls to the display parent
interface.

For i915, move the hooks next to the other i915 core frontbuffer code in
i915_gem_object_frontbuffer.c. For xe, add new file xe_frontbuffer.c for
the same.

Note: The intel_frontbuffer_flush() calls from
i915_gem_object_frontbuffer.c will partially route back to i915 core via
the parent interface. This is less than stellar.

Reviewed-by: Jouni Högander <jouni.hogander@intel.com>
Link: https://patch.msgid.link/f69b967ed82bbcfd60ffa77ba197b26a1399f09f.1772475391.git.jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>