This is a note to let you know that I've just added the patch titled drm/amdgpu: fix dereference null return value for the function amdgpu_vm_pt_parent to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: drm-amdgpu-fix-dereference-null-return-value-for-the.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit 2b5220893df67dc27009bfaa0950406ee0ff145e Author: Jesse Zhang <jesse.zhang@xxxxxxx> Date: Thu May 23 17:14:45 2024 +0800 drm/amdgpu: fix dereference null return value for the function amdgpu_vm_pt_parent [ Upstream commit 511a623fb46a6cf578c61d4f2755783c48807c77 ] The pointer parent may be NULLed by the function amdgpu_vm_pt_parent. To make the code more robust, check the pointer parent. Signed-off-by: Jesse Zhang <Jesse.Zhang@xxxxxxx> Suggested-by: Christian König <christian.koenig@xxxxxxx> Reviewed-by: Christian König <christian.koenig@xxxxxxx> Signed-off-by: Alex Deucher <alexander.deucher@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c index 0d51222f6f8eb..026a3db947298 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_vm_pt.c @@ -766,11 +766,15 @@ int amdgpu_vm_pde_update(struct amdgpu_vm_update_params *params, struct amdgpu_vm_bo_base *entry) { struct amdgpu_vm_bo_base *parent = amdgpu_vm_pt_parent(entry); - struct amdgpu_bo *bo = parent->bo, *pbo; + struct amdgpu_bo *bo, *pbo; struct amdgpu_vm *vm = params->vm; uint64_t pde, pt, flags; unsigned int level; + if (WARN_ON(!parent)) + return -EINVAL; + + bo = parent->bo; for (level = 0, pbo = bo->parent; pbo; ++level) pbo = pbo->parent;