RE: [PATCH v3] drm/amdgpu: skip BOs being torn down during GTT recovery

AMD General

> -----Original Message-----
> From: Zhang, Yifan <[email protected]>
> Sent: Wednesday, August 5, 2026 4:58 PM
> To: [email protected]
> Cc: Deucher, Alexander <[email protected]>; Koenig, Christian
> <[email protected]>; Francis, David <[email protected]>; Yuan,
> Perry <[email protected]>; Zhang, Yifan <[email protected]>
> Subject: [PATCH v3] drm/amdgpu: skip BOs being torn down during GTT recovery
>
> A GPU reset can race with BO teardown after the BO's GTT resource has been
> marked for deletion but before its drm_mm node is removed. In this window,
> amdgpu_gtt_mgr_recover() can treat the node as a live BO and try to restore its
> GART mapping while its TT backing is being destroyed.
>
> Recolor the GTT node from amdgpu_bo_delete_mem_notify() so that recovery skips
> it, reusing the existing color for ranges without a BO. The range stays allocated until
> the resource is freed.
>
> This prevents reset recovery from accessing a BO whose backing storage is no
> longer valid.
>
> v2: refine commit message. (David Francis)
> v3: Remove new BO color. (Christian)
>
> Signed-off-by: Yifan Zhang <[email protected]>

LGTM,
Reviewed-by: Perry Yuan <[email protected]>

Best Regards.

Perry.

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c | 23 +++++++++++++++++++++
>  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c     |  3 +++
>  drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h     |  1 +
>  3 files changed, 27 insertions(+)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> index 0ea32561c4bc..6219233ff712 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_gtt_mgr.c
> @@ -102,6 +102,29 @@ bool amdgpu_gtt_mgr_has_gart_addr(struct ttm_resource
> *res)
>       return drm_mm_node_allocated(&node->mm_nodes[0]);
>  }
>
> +/**
> + * amdgpu_gtt_mgr_mark_bo_teardown - exclude a BO from GART recovery
> + *
> + * @tbo: TTM BO whose TT backing is about to be destroyed
> + *
> + * Keep the GART range allocated until the resource is freed, but make
> +recovery
> + * treat it like a range without a BO so it isn't touched after TT
> +teardown has
> + * started.
> + */
> +void amdgpu_gtt_mgr_mark_bo_teardown(struct ttm_buffer_object *tbo) {
> +     struct amdgpu_device *adev = amdgpu_ttm_adev(tbo->bdev);
> +     struct ttm_range_mgr_node *node = to_ttm_range_mgr_node(tbo-
> >resource);
> +     struct amdgpu_gtt_mgr *mgr = &adev->mman.gtt_mgr;
> +
> +     dma_resv_assert_held(tbo->base.resv);
> +
> +     spin_lock(&mgr->lock);
> +     if (drm_mm_node_allocated(&node->mm_nodes[0]))
> +             node->mm_nodes[0].color =
> GART_ENTRY_WITHOUT_BO_COLOR;
> +     spin_unlock(&mgr->lock);
> +}
> +
>  /**
>   * amdgpu_gtt_mgr_new - allocate a new node
>   *
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index c4094edbdff1..a9067305b26d 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -1694,6 +1694,9 @@ static int amdgpu_ttm_access_memory(struct
> ttm_buffer_object *bo,  static void  amdgpu_bo_delete_mem_notify(struct
> ttm_buffer_object *bo)  {
> +     if (bo->resource && bo->resource->mem_type == TTM_PL_TT)
> +             amdgpu_gtt_mgr_mark_bo_teardown(bo);
> +
>       amdgpu_bo_move_notify(bo, false, NULL);  }
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
> index ff9e2e346609..af1e7fcc7175 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.h
> @@ -145,6 +145,7 @@ int amdgpu_vram_mgr_init(struct amdgpu_device *adev);
> void amdgpu_vram_mgr_fini(struct amdgpu_device *adev);
>
>  bool amdgpu_gtt_mgr_has_gart_addr(struct ttm_resource *mem);
> +void amdgpu_gtt_mgr_mark_bo_teardown(struct ttm_buffer_object *tbo);
>  void amdgpu_gtt_mgr_recover(struct amdgpu_gtt_mgr *mgr);
>
>  int amdgpu_gtt_mgr_alloc_entries(struct amdgpu_gtt_mgr *mgr,
> --
> 2.43.0