On 5/15/25 11:46, Jesse.Zhang wrote:
> The current cleanup order during file descriptor close can lead to
> a race condition where the eviction fence worker attempts to access
> a destroyed mutex from the user queue manager:
>
> [ 517.294055] DEBUG_LOCKS_WARN_ON(lock->magic != lock)
> [ 517.294060] WARNING: CPU: 8 PID: 2030 at kernel/locking/mutex.c:564
> [ 517.294094] Workqueue: events amdgpu_eviction_fence_suspend_worker [amdgpu]
>
> The issue occurs because:
> 1. We destroy the user queue manager (including its mutex) first
> 2. Then try to destroy eviction fences which may have pending work
> 3. The eviction fence worker may try to access the already-destroyed mutex
>
> Fix this by reordering the cleanup to:
> 1. First mark the fd as closing and destroy eviction fences,
> which flushes any pending work
> 2. Then safely destroy the user queue manager after we're certain
> no more fence work will be executed
>
> v2: remove the copy in amdgpu_driver_postclose_kms() (Christian)
>
> Signed-off-by: Jesse Zhang <jesse.zh...@amd.com>
Reviewed-by: Christian König <christian.koe...@amd.com>
We should probably clean that up further, but that is unecessary here.
Regards,
Christian.
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 2 +-
> drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c | 5 -----
> 2 files changed, 1 insertion(+), 6 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> index 4ddd08ce8885..4db92e0a60da 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
> @@ -2913,8 +2913,8 @@ static int amdgpu_drm_release(struct inode *inode,
> struct file *filp)
>
> if (fpriv) {
> fpriv->evf_mgr.fd_closing = true;
> - amdgpu_userq_mgr_fini(&fpriv->userq_mgr);
> amdgpu_eviction_fence_destroy(&fpriv->evf_mgr);
> + amdgpu_userq_mgr_fini(&fpriv->userq_mgr);
> }
>
> return drm_release(inode, filp);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> index 9fbb04aee97b..d2ce7d86dbc8 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
> @@ -1502,11 +1502,6 @@ void amdgpu_driver_postclose_kms(struct drm_device
> *dev,
> amdgpu_bo_unreserve(pd);
> }
>
> - if (!fpriv->evf_mgr.fd_closing) {
> - fpriv->evf_mgr.fd_closing = true;
> - amdgpu_userq_mgr_fini(&fpriv->userq_mgr);
> - amdgpu_eviction_fence_destroy(&fpriv->evf_mgr);
> - }
> amdgpu_ctx_mgr_fini(&fpriv->ctx_mgr);
> amdgpu_vm_fini(adev, &fpriv->vm);
>
