Claude review: drm/xe/drm_ras: Add per node cleanup action

[Claude Code Review Bot <claude-review@example.com>]

Patch Review

**Verdict: Has a bug — double cleanup on `drmm_add_action_or_reset` failure.**

The overall refactoring from a single bulk cleanup action (`xe_drm_ras_unregister_nodes`) to per-node cleanup actions is a sound improvement. It guarantees that each successfully registered node is individually cleaned up during unwind, which solves the problem described.

However, this code has a bug:

```c
ret = drmm_add_action_or_reset(&xe->drm, cleanup_node, node);
if (ret) {
    cleanup_node(&xe->drm, node);
    return ret;
}
```

The `_or_reset` suffix in `drmm_add_action_or_reset` means the action is **already called on failure** (see `include/drm/drm_managed.h` line 38-39: *"upon failure @action is directly called for any cleanup work"*). Explicitly calling `cleanup_node()` again results in:
1. Double call to `drm_ras_node_unregister(node)` — the second call operates on an already-unregistered node
2. Double `kfree(node->device_name)` — harmless because the first call NULLs the pointer, but still wrong

The fix is simple — just `return ret`:

```c
ret = drmm_add_action_or_reset(&xe->drm, cleanup_node, node);
if (ret)
    return ret;
```

**Commit message nit**: The commit message repeats the same description as patch 2 verbatim ("cleanup_node_param() is not registered in case of counter allocation failure, which results in stale memory of previous node..."). Since patch 2 already fixed the counter allocation issue, patch 3's description should focus on what it actually does: moving to per-node drmm cleanup actions for robust unwind and simplification.

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Generated by Claude Code Patch Reviewer