From 82b9c55b1edfcb87f5568add56bc7313f5893b60 Mon Sep 17 00:00:00 2001 From: =?utf8?q?Christian=20K=C3=B6nig?= Date: Fri, 27 Nov 2015 16:49:00 +0100 Subject: [PATCH] drm/amdgpu: fix VM page table reference counting MIME-Version: 1.0 Content-Type: text/plain; charset=utf8 Content-Transfer-Encoding: 8bit We use the reservation object of the page directory for the page tables as well, because of this the page directory should be freed last. Ensure that by keeping a reference from the page tables to the directory. Signed-off-by: Christian König Signed-off-by: Alex Deucher --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_object.c | 1 + drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c | 5 +++++ 3 files changed, 7 insertions(+) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index 251b14736de9..670fefb56945 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -539,6 +539,7 @@ struct amdgpu_bo { /* Constant after initialization */ struct amdgpu_device *adev; struct drm_gem_object gem_base; + struct amdgpu_bo *parent; struct ttm_bo_kmap_obj dma_buf_vmap; pid_t pid; diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c index 0d524384ff79..c3ce103b6a33 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_object.c @@ -100,6 +100,7 @@ static void amdgpu_ttm_bo_destroy(struct ttm_buffer_object *tbo) list_del_init(&bo->list); mutex_unlock(&bo->adev->gem.mutex); drm_gem_object_release(&bo->gem_base); + amdgpu_bo_unref(&bo->parent); kfree(bo->metadata); kfree(bo); } diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c index ae037e5b6ad0..a582ef553499 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm.c @@ -1079,6 +1079,11 @@ int amdgpu_vm_bo_map(struct amdgpu_device *adev, if (r) goto error_free; + /* Keep a reference to the page table to avoid freeing + * them up in the wrong order. + */ + pt->parent = amdgpu_bo_ref(vm->page_directory); + r = amdgpu_vm_clear_bo(adev, pt); if (r) { amdgpu_bo_unref(&pt); -- 2.20.1