Claude review: drm/amdgpu: fix lock leak on ENOMEM in AMDGPU_GEM_OP_GET_MAPPING_INFO

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

Patch Review

**Correctness: Good.** Looking at the function structure in `amdgpu_gem.c:1002-1141`:

1. At line 1016, `drm_gem_object_lookup()` acquires a reference on `gobj`.
2. At lines 1022-1036, `drm_exec_init()` + `drm_exec_lock_obj()` + `amdgpu_vm_lock_pd()` acquire locks tracked by `exec`.
3. The `out_exec` label at line 1137-1140 properly cleans up both via `drm_exec_fini(&exec)` and `drm_gem_object_put(gobj)`.

The original code at the `kvcalloc` failure:
```c
if (!vm_entries)
    return -ENOMEM;
```
skips both cleanup calls. The fix:
```c
if (!vm_entries) {
    r = -ENOMEM;
    goto out_exec;
}
```
correctly routes through the existing cleanup path.

**Comparison with sibling error paths:** Every other error path in this function either jumps to `out_exec` (lines 1028, 1033, 1055-1056, 1059-1060, 1065-1066) or calls `drm_exec_fini(&exec)` inline before the `break` (lines 1047, 1079, 1119, 1131). The fix is consistent with the `goto out_exec` pattern used for all pre-`break` errors.

**One minor observation (not blocking):** The commit message mentions the patch was `Assisted-by: Claude:claude-opus-4-7`. This tag is not a standard kernel tag — the kernel community hasn't settled on a convention for AI-assisted patches. Some maintainers may request removal or conversion. This is a social/process concern, not a code correctness issue.

**No issues found with the code change itself.** The fix is minimal, correct, and addresses a real unprivileged local DoS.

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Generated by Claude Code Patch Reviewer