kernel/linux.git/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c, branch v7.0-rc7

drm/amd: Fix MQD and control stack alignment for non-4K

2026-03-30T20:12:27+00:00

For gfxV9, due to a hardware bug ("based on the comments in the code here [1]"), the control stack of a user-mode compute queue must be allocated immediately after the page boundary of its regular MQD buffer. To handle this, we allocate an enlarged MQD buffer where the first page is used as the MQD and the remaining pages store the control stack. Although these regions share the same BO, they require different memory types: the MQD must be UC (uncached), while the control stack must be NC (non-coherent), matching the behavior when the control stack is allocated in user space. This logic works correctly on systems where the CPU page size matches the GPU page size (4K). However, the current implementation aligns both the MQD and the control stack to the CPU PAGE_SIZE. On systems with a larger CPU page size, the entire first CPU page is marked UC—even though that page may contain multiple GPU pages. The GPU treats the second 4K GPU page inside that CPU page as part of the control stack, but it is incorrectly mapped as UC. This patch fixes the issue by aligning both the MQD and control stack sizes to the GPU page size (4K). The first 4K page is correctly marked as UC for the MQD, and the remaining GPU pages are marked NC for the control stack. This ensures proper memory type assignment on systems with larger CPU page sizes. [1]: https://elixir.bootlin.com/linux/v6.18/source/drivers/gpu/drm/amd/amdkfd/kfd_mqd_manager_v9.c#L118 Acked-by: Felix Kuehling Signed-off-by: Donet Tom Signed-off-by: Alex Deucher (cherry picked from commit 998d6781410de1c4b787fdbf6c56e851ea7fa553)

Convert remaining multi-line kmalloc_obj/flex GFP_KERNEL uses

2026-02-22T16:26:33+00:00

Conversion performed via this Coccinelle script: // SPDX-License-Identifier: GPL-2.0-only // Options: --include-headers-for-types --all-includes --include-headers --keep-comments virtual patch @gfp depends on patch && !(file in "tools") && !(file in "samples")@ identifier ALLOC = {kmalloc_obj,kmalloc_objs,kmalloc_flex, kzalloc_obj,kzalloc_objs,kzalloc_flex, kvmalloc_obj,kvmalloc_objs,kvmalloc_flex, kvzalloc_obj,kvzalloc_objs,kvzalloc_flex}; @@ ALLOC(... - , GFP_KERNEL ) $ make coccicheck MODE=patch COCCI=gfp.cocci Build and boot tested x86_64 with Fedora 42's GCC and Clang: Linux version 6.19.0+ (user@host) (gcc (GCC) 15.2.1 20260123 (Red Hat 15.2.1-7), GNU ld version 2.44-12.fc42) #1 SMP PREEMPT_DYNAMIC 1970-01-01 Linux version 6.19.0+ (user@host) (clang version 20.1.8 (Fedora 20.1.8-4.fc42), LLD 20.1.8) #1 SMP PREEMPT_DYNAMIC 1970-01-01 Signed-off-by: Kees Cook Signed-off-by: Linus Torvalds

Convert 'alloc_obj' family to use the new default GFP_KERNEL argument

2026-02-22T01:09:51+00:00

This was done entirely with mindless brute force, using git grep -l '\

treewide: Replace kmalloc with kmalloc_obj for non-scalar types

2026-02-21T09:02:28+00:00

This is the result of running the Coccinelle script from scripts/coccinelle/api/kmalloc_objs.cocci. The script is designed to avoid scalar types (which need careful case-by-case checking), and instead replace kmalloc-family calls that allocate struct or union object instances: Single allocations: kmalloc(sizeof(TYPE), ...) are replaced with: kmalloc_obj(TYPE, ...) Array allocations: kmalloc_array(COUNT, sizeof(TYPE), ...) are replaced with: kmalloc_objs(TYPE, COUNT, ...) Flex array allocations: kmalloc(struct_size(PTR, FAM, COUNT), ...) are replaced with: kmalloc_flex(*PTR, FAM, COUNT, ...) (where TYPE may also be *VAR) The resulting allocations no longer return "void *", instead returning "TYPE *". Signed-off-by: Kees Cook

drm/amdgpu: Drop MMIO_REMAP domain bit and keep it Internal

2026-01-10T19:21:35+00:00

"AMDGPU_GEM_DOMAIN_MMIO_REMAP" - Never activated as UAPI and it turned out that this was to inflexible. Allocate the MMIO_REMAP buffer object as a regular GEM BO and explicitly move it into the fixed AMDGPU_PL_MMIO_REMAP placement at the TTM level. This avoids relying on GEM domain bits for MMIO_REMAP, keeps the placement purely internal, and makes the lifetime and pinning of the global MMIO_REMAP BO explicit. The BO is pinned in TTM so it cannot be migrated or evicted. The corresponding free path relies on normal DRM teardown ordering, where no further user ioctls can access the global BO once TTM teardown begins. v2 (Srini): - Updated patch title. - Drop use of AMDGPU_GEM_DOMAIN_MMIO_REMAP in amdgpu_ttm.c. The MMIO_REMAP domain bit is removed from UAPI, so keep the MMIO_REMAP BO allocation domain-less (bp.domain = 0) and rely on the TTM placement (AMDGPU_PL_MMIO_REMAP) for backing/pinning. - Keep fdinfo/mem-stats visibility for MMIO_REMAP by classifying BOs based on bo->tbo.resource->mem_type == AMDGPU_PL_MMIO_REMAP, since the domain bit is removed. v3: Squash patches #1 & #3 Fixes: 056132483724 ("drm/amdgpu/uapi: Introduce AMDGPU_GEM_DOMAIN_MMIO_REMAP") Fixes: 2a7a794eb82c ("drm/amdgpu/ttm: Allocate/Free 4K MMIO_REMAP Singleton") Cc: Alex Deucher Cc: Christian König Cc: Leo Liu Cc: Ruijing Dong Cc: David (Ming Qiang) Wu Signed-off-by: Srinivasan Shanmugam Signed-off-by: Christian König Reviewed-by: Alex Deucher Signed-off-by: Alex Deucher

drm/amdgpu: reserve umf hole size at vram high end for gfx v12.1

2026-01-05T21:59:57+00:00

This region is reserved by firmware thus carve it out in driver. v2: set reserve size based on aid configuration. Signed-off-by: Le Ma Reviewed-by: Hawking Zhang Signed-off-by: Alex Deucher

drm/amd: Convert DRM_() to drm_()

2026-01-05T21:59:55+00:00

The drm_*() macros include the device which is helpful for debugging issues in multi-GPU systems. Signed-off-by: Mario Limonciello (AMD) Reviewed-by: Aurabindo Pillai Signed-off-by: Alex Deucher

drm/amd: Drop amdgpu prefix from message prints

2026-01-05T21:59:55+00:00

Hardcoding the prefix isn't necessary when using drm_* or dev_* message prints. Signed-off-by: Mario Limonciello (AMD) Reviewed-by: Aurabindo Pillai Signed-off-by: Alex Deucher

drm/amdgpu: pass the entity to use to ttm public functions

2025-12-08T19:31:27+00:00

This way the caller can select the one it wants to use. Signed-off-by: Pierre-Eric Pelloux-Prayer Reviewed-by: Christian König Acked-by: Felix Kuehling Signed-off-by: Alex Deucher

drm/amdgpu: pass the entity to use to amdgpu_ttm_map_buffer

2025-12-08T19:31:23+00:00

This way the caller can select the one it wants to use. Signed-off-by: Pierre-Eric Pelloux-Prayer Reviewed-by: Christian König Signed-off-by: Alex Deucher