kernel/drivers/gpu/drm/drm_buddy.c, branch linux-rolling-lts

drm/buddy: Prevent BUG_ON by validating rounded allocation

2026-03-04T12:21:10Z

[ Upstream commit 5488a29596cdba93a60a79398dc9b69d5bdadf92 ] When DRM_BUDDY_CONTIGUOUS_ALLOCATION is set, the requested size is rounded up to the next power-of-two via roundup_pow_of_two(). Similarly, for non-contiguous allocations with large min_block_size, the size is aligned up via round_up(). Both operations can produce a rounded size that exceeds mm->size, which later triggers BUG_ON(order > mm->max_order). Example scenarios: - 9G CONTIGUOUS allocation on 10G VRAM memory: roundup_pow_of_two(9G) = 16G > 10G - 9G allocation with 8G min_block_size on 10G VRAM memory: round_up(9G, 8G) = 16G > 10G Fix this by checking the rounded size against mm->size. For non-contiguous or range allocations where size > mm->size is invalid, return -EINVAL immediately. For contiguous allocations without range restrictions, allow the request to fall through to the existing __alloc_contig_try_harder() fallback. This ensures invalid user input returns an error or uses the fallback path instead of hitting BUG_ON. v2: (Matt A) - Add Fixes, Cc stable, and Closes tags for context Closes: https://gitlab.freedesktop.org/drm/xe/kernel/-/issues/6712 Fixes: 0a1844bf0b53 ("drm/buddy: Improve contiguous memory allocation") Cc: # v6.7+ Cc: Christian König Cc: Arunpravin Paneer Selvam Suggested-by: Matthew Auld Signed-off-by: Sanjay Yadav Reviewed-by: Matthew Auld Reviewed-by: Arunpravin Paneer Selvam Signed-off-by: Arunpravin Paneer Selvam Link: https://patch.msgid.link/20260108113227.2101872-5-sanjay.kumar.yadav@intel.com Signed-off-by: Sasha Levin

drm/buddy: release free_trees array on buddy mm teardown

2026-02-26T22:59:13Z

[ Upstream commit 7d0507772406e129329983b8b807e5b499bd74fd ] During initialization of DRM buddy memory manager at drm_buddy_init, mm->free_trees array is allocated for both clear and dirty RB trees. During cleanup happening at drm_buddy_fini it is never freed, leading to following memory leaks observed on xe module load & unload cycles: kmemleak_alloc+0x4a/0x90 __kmalloc_cache_noprof+0x488/0x800 drm_buddy_init+0xc2/0x330 [drm_buddy] __xe_ttm_vram_mgr_init+0xc3/0x190 [xe] xe_ttm_stolen_mgr_init+0xf5/0x9d0 [xe] xe_device_probe+0x326/0x9e0 [xe] xe_pci_probe+0x39a/0x610 [xe] local_pci_probe+0x47/0xb0 pci_device_probe+0xf3/0x260 really_probe+0xf1/0x3c0 __driver_probe_device+0x8c/0x180 driver_probe_device+0x24/0xd0 __driver_attach+0x10f/0x220 bus_for_each_dev+0x7f/0xe0 driver_attach+0x1e/0x30 bus_add_driver+0x151/0x290 Deallocate array for free trees when cleaning up buddy memory manager in the same way as if going through out_free_tree label. Fixes: d4cd665c98c1 ("drm/buddy: Separate clear and dirty free block trees") Signed-off-by: Michał Grzelak Reviewed-by: Lucas De Marchi Reviewed-by: Matthew Auld Signed-off-by: Arunpravin Paneer Selvam Link: https://patch.msgid.link/20251208102714.4008260-2-michal.grzelak@intel.com Signed-off-by: Sasha Levin

drm/buddy: Separate clear and dirty free block trees

2026-01-08T09:17:16Z

commit d4cd665c98c144dd6ad5d66d30396e13d23118c9 upstream. Maintain two separate RB trees per order - one for clear (zeroed) blocks and another for dirty (uncleared) blocks. This separation improves code clarity and makes it more obvious which tree is being searched during allocation. It also improves scalability and efficiency when searching for a specific type of block, avoiding unnecessary checks and making the allocator more predictable under fragmentation. The changes have been validated using the existing drm_buddy_test KUnit test cases, along with selected graphics workloads, to ensure correctness and avoid regressions. v2: Missed adding the suggested-by tag. Added it in v2. v3(Matthew): - Remove the double underscores from the internal functions. - Rename the internal functions to have less generic names. - Fix the error handling code. - Pass tree argument for the tree macro. - Use the existing dirty/free bit instead of new tree field. - Make free_trees[] instead of clear_tree and dirty_tree for more cleaner approach. v4: - A bug was reported by Intel CI and it is fixed by Matthew Auld. - Replace the get_root function with &mm->free_trees[tree][order] (Matthew) - Remove the unnecessary rbtree_is_empty() check (Matthew) - Remove the unnecessary get_tree_for_flags() function. - Rename get_tree_for_block() name with get_block_tree() for more clarity. v5(Jani Nikula): - Don't use static inline in .c files. - enum free_tree and enumerator names are quite generic for a header and usage and the whole enum should be an implementation detail. v6: - Rewrite the __force_merge() function using the rb_last() and rb_prev(). v7(Matthew): - Replace the open-coded tree iteration for loops with the for_each_free_tree() macro throughout the code. - Fixed out_free_roots to prevent double decrement of i, addressing potential crash. - Replaced enum drm_buddy_free_tree with unsigned int in for_each_free_tree loops. Cc: stable@vger.kernel.org Fixes: a68c7eaa7a8f ("drm/amdgpu: Enable clear page functionality") Signed-off-by: Arunpravin Paneer Selvam Suggested-by: Matthew Auld Reviewed-by: Matthew Auld Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/4260 Link: https://lore.kernel.org/r/20251006095124.1663-2-Arunpravin.PaneerSelvam@amd.com Signed-off-by: Greg Kroah-Hartman

drm/buddy: Optimize free block management with RB tree

2026-01-08T09:17:16Z

commit c178e534fff1d5a74da80ea03b20e2b948a00113 upstream. Replace the freelist (O(n)) used for free block management with a red-black tree, providing more efficient O(log n) search, insert, and delete operations. This improves scalability and performance when managing large numbers of free blocks per order (e.g., hundreds or thousands). In the VK-CTS memory stress subtest, the buddy manager merges fragmented memory and inserts freed blocks into the freelist. Since freelist insertion is O(n), this becomes a bottleneck as fragmentation increases. Benchmarking shows list_insert_sorted() consumes ~52.69% CPU with the freelist, compared to just 0.03% with the RB tree (rbtree_insert.isra.0), despite performing the same sorted insert. This also improves performance in heavily fragmented workloads, such as games or graphics tests that stress memory. As the buddy allocator evolves with new features such as clear-page tracking, the resulting fragmentation and complexity have grown. These RB-tree based design changes are introduced to address that growth and ensure the allocator continues to perform efficiently under fragmented conditions. The RB tree implementation with separate clear/dirty trees provides: - O(n log n) aggregate complexity for all operations instead of O(n^2) - Elimination of soft lockups and system instability - Improved code maintainability and clarity - Better scalability for large memory systems - Predictable performance under fragmentation v3(Matthew): - Remove RB_EMPTY_NODE check in force_merge function. - Rename rb for loop macros to have less generic names and move to .c file. - Make the rb node rb and link field as union. v4(Jani Nikula): - The kernel-doc comment should be "/**" - Move all the rbtree macros to rbtree.h and add parens to ensure correct precedence. v5: - Remove the inline in a .c file (Jani Nikula). v6(Peter Zijlstra): - Add rb_add() function replacing the existing rbtree_insert() code. v7: - A full walk iteration in rbtree is slower than the list (Peter Zijlstra). - The existing rbtree_postorder_for_each_entry_safe macro should be used in scenarios where traversal order is not a critical factor (Christian). v8(Matthew): - Remove the rbtree_is_empty() check in this patch as well. Cc: stable@vger.kernel.org Fixes: a68c7eaa7a8f ("drm/amdgpu: Enable clear page functionality") Signed-off-by: Arunpravin Paneer Selvam Reviewed-by: Matthew Auld Link: https://lore.kernel.org/r/20251006095124.1663-1-Arunpravin.PaneerSelvam@amd.com Signed-off-by: Greg Kroah-Hartman

Merge tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel

2025-07-31T02:26:49Z

Pull drm updates from Dave Airlie: "Highlights: - Intel xe enable Panthor Lake, started adding WildCat Lake - amdgpu has a bunch of reset improvments along with the usual IP updates - msm got VM_BIND support which is important for vulkan sparse memory - more drm_panic users - gpusvm common code to handle a bunch of core SVM work outside drivers. Detail summary: Changes outside drm subdirectory: - 'shrink_shmem_memory()' for better shmem/hibernate interaction - Rust support infrastructure: - make ETIMEDOUT available - add size constants up to SZ_2G - add DMA coherent allocation bindings - mtd driver for Intel GPU non-volatile storage - i2c designware quirk for Intel xe core: - atomic helpers: tune enable/disable sequences - add task info to wedge API - refactor EDID quirks - connector: move HDR sink to drm_display_info - fourcc: half-float and 32-bit float formats - mode_config: pass format info to simplify dma-buf: - heaps: Give CMA heap a stable name ci: - add device tree validation and kunit displayport: - change AUX DPCD access probe address - add quirk for DPCD probe - add panel replay definitions - backlight control helpers fbdev: - make CONFIG_FIRMWARE_EDID available on all arches fence: - fix UAF issues format-helper: - improve tests gpusvm: - introduce devmem only flag for allocation - add timeslicing support to GPU SVM ttm: - improve eviction sched: - tracing improvements - kunit improvements - memory leak fixes - reset handling improvements color mgmt: - add hardware gamma LUT handling helpers bridge: - add destroy hook - switch to reference counted drm_bridge allocations - tc358767: convert to devm_drm_bridge_alloc - improve CEC handling panel: - switch to reference counter drm_panel allocations - fwnode panel lookup - Huiling hl055fhv028c support - Raspberry Pi 7" 720x1280 support - edp: KDC KD116N3730A05, N160JCE-ELL CMN, N116BCJ-EAK - simple: AUO P238HAN01 - st7701: Winstar wf40eswaa6mnn0 - visionox: rm69299-shift - Renesas R61307, Renesas R69328 support - DJN HX83112B hdmi: - add CEC handling - YUV420 output support xe: - WildCat Lake support - Enable PanthorLake by default - mark BMG as SRIOV capable - update firmware recommendations - Expose media OA units - aux-bux support for non-volatile memory - MTD intel-dg driver for non-volatile memory - Expose fan control and voltage regulator in sysfs - restructure migration for multi-device - Restore GuC submit UAF fix - make GEM shrinker drm managed - SRIOV VF Post-migration recovery of GGTT nodes - W/A additions/reworks - Prefetch support for svm ranges - Don't allocate managed BO for each policy change - HWMON fixes for BMG - Create LRC BO without VM - PCI ID updates - make SLPC debugfs files optional - rework eviction rejection of bound external BOs - consolidate PAT programming logic for pre/post Xe2 - init changes for flicker-free boot - Enable GuC Dynamic Inhibit Context switch i915: - drm_panic support for i915/xe - initial flip queue off by default for LNL/PNL - Wildcat Lake Display support - Support for DSC fractional link bpp - Support for simultaneous Panel Replay and Adaptive sync - Support for PTL+ double buffer LUT - initial PIPEDMC event handling - drm_panel_follower support - DPLL interface renames - allocate struct intel_display dynamically - flip queue preperation - abstract DRAM detection better - avoid GuC scheduling stalls - remove DG1 force probe requirement - fix MEI interrupt handler on RT kernels - use backlight control helpers for eDP - more shared display code refactoring amdgpu: - add userq slot to INFO ioctl - SR-IOV hibernation support - Suspend improvements - Backlight improvements - Use scaling for non-native eDP modes - cleaner shader updates for GC 9.x - Remove fence slab - SDMA fw checks for userq support - RAS updates - DMCUB updates - DP tunneling fixes - Display idle D3 support - Per queue reset improvements - initial smartmux support amdkfd: - enable KFD on loongarch - mtype fix for ext coherent system memory radeon: - CS validation additional GL extensions - drop console lock during suspend/resume - bump driver version msm: - VM BIND support - CI: infrastructure updates - UBWC single source of truth - decouple GPU and KMS support - DP: rework I/O accessors - DPU: SM8750 support - DSI: SM8750 support - GPU: X1-45 support and speedbin support for X1-85 - MDSS: SM8750 support nova: - register! macro improvements - DMA object abstraction - VBIOS parser + fwsec lookup - sysmem flush page support - falcon: generic falcon boot code and HAL - FWSEC-FRTS: fb setup and load/execute ivpu: - Add Wildcat Lake support - Add turbo flag ast: - improve hardware generations implementation imx: - IMX8qxq Display Controller support lima: - Rockchip RK3528 GPU support nouveau: - fence handling cleanup panfrost: - MT8370 support - bo labeling - 64-bit register access qaic: - add RAS support rockchip: - convert inno_hdmi to a bridge rz-du: - add RZ/V2H(P) support - MIPI-DSI DCS support sitronix: - ST7567 support sun4i: - add H616 support tidss: - add TI AM62L support - AM65x OLDI bridge support bochs: - drm panic support vkms: - YUV and R* format support - use faux device vmwgfx: - fence improvements hyperv: - move out of simple - add drm_panic support" * tag 'drm-next-2025-07-30' of https://gitlab.freedesktop.org/drm/kernel: (1479 commits) drm/tidss: oldi: convert to devm_drm_bridge_alloc() API drm/tidss: encoder: convert to devm_drm_bridge_alloc() drm/amdgpu: move reset support type checks into the caller drm/amdgpu/sdma7: re-emit unprocessed state on ring reset drm/amdgpu/sdma6: re-emit unprocessed state on ring reset drm/amdgpu/sdma5.2: re-emit unprocessed state on ring reset drm/amdgpu/sdma5: re-emit unprocessed state on ring reset drm/amdgpu/gfx12: re-emit unprocessed state on ring reset drm/amdgpu/gfx11: re-emit unprocessed state on ring reset drm/amdgpu/gfx10: re-emit unprocessed state on ring reset drm/amdgpu/gfx9.4.3: re-emit unprocessed state on kcq reset drm/amdgpu/gfx9: re-emit unprocessed state on kcq reset drm/amdgpu: Add WARN_ON to the resource clear function drm/amd/pm: Use cached metrics data on SMUv13.0.6 drm/amd/pm: Use cached data for min/max clocks gpu: nova-core: fix bounds check in PmuLookupTableEntry::new drm/amdgpu: Replace HQD terminology with slots naming drm/amdgpu: Add user queue instance count in HW IP info drm/amd/amdgpu: Add helper functions for isp buffers drm/amd/amdgpu: Initialize swnode for ISP MFD device ...

drm/amdgpu: Reset the clear flag in buddy during resume

2025-07-16T10:50:32Z

- Added a handler in DRM buddy manager to reset the cleared flag for the blocks in the freelist. - This is necessary because, upon resuming, the VRAM becomes cluttered with BIOS data, yet the VRAM backend manager believes that everything has been cleared. v2: - Add lock before accessing drm_buddy_clear_reset_blocks()(Matthew Auld) - Force merge the two dirty blocks.(Matthew Auld) - Add a new unit test case for this issue.(Matthew Auld) - Having this function being able to flip the state either way would be good. (Matthew Brost) v3(Matthew Auld): - Do merge step first to avoid the use of extra reset flag. Signed-off-by: Arunpravin Paneer Selvam Suggested-by: Christian König Acked-by: Christian König Reviewed-by: Matthew Auld Cc: stable@vger.kernel.org Fixes: a68c7eaa7a8f ("drm/amdgpu: Enable clear page functionality") Closes: https://gitlab.freedesktop.org/drm/amd/-/issues/3812 Signed-off-by: Christian König Link: https://lore.kernel.org/r/20250716075125.240637-2-Arunpravin.PaneerSelvam@amd.com

drm: Include

2025-06-16T07:01:23Z

Fix the compile-time warnings drivers/gpu/drm/drm_atomic.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_state_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_atomic_uapi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_auth.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_buddy.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_color_mgmt.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_connector.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_damage_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_debugfs_crc.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_drv.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_edid.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_exec.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_fb_dma_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_file.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_flip_work.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_format_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_gpusvm.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_gpuvm.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_managed.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mipi_dbi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mipi_dsi.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_mode_config.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_modeset_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_modeset_lock.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_panic.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_plane.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_plane_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_print.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_privacy_screen.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_self_refresh_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_simple_kms_helper.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_suballoc.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_syncobj.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_vblank_work.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_vma_manager.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/drm_writeback.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/lib/drm_random.c: warning: EXPORT_SYMBOL() is used, but #include is missing drivers/gpu/drm/tests/drm_kunit_helpers.c: warning: EXPORT_SYMBOL() is used, but #include is missing Signed-off-by: Thomas Zimmermann Fixes: a934a57a42f6 ("scripts/misc-check: check missing #include when W=1") Reviewed-by: André Almeida Cc: Masahiro Yamada Cc: Nathan Chancellor Link: https://lore.kernel.org/r/20250612121633.229222-3-tzimmermann@suse.de

drm/buddy: Add a testcase to verify the multiroot fini

2025-01-14T15:13:19Z

- Added a testcase to verify the multiroot force merge fini. - Added a new field in_use to track the mm freed status. v2:(Matthew) - Add kunit_fail_current_test() when WARN_ON is true. Signed-off-by: Arunpravin Paneer Selvam Signed-off-by: Lin.Cao Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20241226070116.309290-2-Arunpravin.PaneerSelvam@amd.com

drm/buddy: fix issue that force_merge cannot free all roots

2025-01-14T15:12:28Z

If buddy manager have more than one roots and each root have sub-block need to be free. When drm_buddy_fini called, the first loop of force_merge will merge and free all of the sub block of first root, which offset is 0x0 and size is biggest(more than have of the mm size). In subsequent force_merge rounds, if we use 0 as start and use remaining mm size as end, the block of other roots will be skipped in __force_merge function. It will cause the other roots can not be freed. Solution: use roots' offset as the start could fix this issue. Signed-off-by: Lin.Cao Signed-off-by: Arunpravin Paneer Selvam Reviewed-by: Matthew Auld Link: https://patchwork.freedesktop.org/patch/msgid/20241226070116.309290-1-Arunpravin.PaneerSelvam@amd.com

drm/buddy: Add start address support to trim function

2024-08-07T22:19:00Z

- Add a new start parameter in trim function to specify exact address from where to start the trimming. This would help us in situations like if drivers would like to do address alignment for specific requirements. - Add a new flag DRM_BUDDY_TRIM_DISABLE. Drivers can use this flag to disable the allocator trimming part. This patch enables the drivers control trimming and they can do it themselves based on the application requirements. v1:(Matthew) - check new_start alignment with min chunk_size - use range_overflows() Signed-off-by: Arunpravin Paneer Selvam Acked-by: Alex Deucher Acked-by: Christian König Signed-off-by: Alex Deucher (cherry picked from commit db65eb46de135338d6177f8853e0fd208f19d63e)