Unsuspended GPU access via premature fence removal

Fence lifetime errors in Linux 6.16 amdgpu allow local users to access evicted GPU buffers by closing a duplicate handle. The amdgpu_gem_object_close() function removes the eviction fence before checking remaining buffer-mapping references, so GPU queues continue accessing the buffer during eviction. Reachability requires access to amdgpu user queues and duplicate handles in the same file; the published evidence does not establish data disclosure, privilege escalation, or a specific crash outcome.