Claude review: drm/nouveau/kms/nvd9-: Use contiguous memory for CRC notifier context

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

Patch Review

**Correctness of the core fix:**

The old code called `nvif_mem_ctor_map()` which internally passes `NULL, 0` for the argv/argc parameters to `nvif_mem_ctor()`:

```c
// nvif/mem.c:31-32 (old path)
int ret = nvif_mem_ctor(mmu, name, mmu->mem, NVIF_MEM_MAPPABLE | type,
                        0, size, NULL, 0, mem);
```

The new code replaces this with a direct `nvif_mem_ctor()` call that passes a `gf100_mem_v0` struct with `.contig = true`:

```c
ret = nvif_mem_ctor(mmu, "kmsCrcNtfy", mmu->mem, NVIF_MEM_VRAM | NVIF_MEM_MAPPABLE, 0, len,
                    &(struct gf100_mem_v0) {
                            .contig = true,
                    }, sizeof(struct gf100_mem_v0), &ctx->mem);
```

This is correct. The compound literal zero-initializes `.version` to 0, matching the `v0` convention. The `gf100_mem_v0` data gets copied into `args->data[]` inside `nvif_mem_ctor_type()` (mem.c:70) and forwarded to the firmware/kernel memory handler, which will honor the contiguous flag.

The flags `NVIF_MEM_VRAM | NVIF_MEM_MAPPABLE` match exactly what `nvif_mem_ctor_map()` was computing internally (`NVIF_MEM_MAPPABLE | type` where `type` was `NVIF_MEM_VRAM`).

**Error handling:**

The separate `nvif_object_map()` call after `nvif_mem_ctor()` correctly jumps to `fail_fini` on failure, which calls `nvif_mem_dtor()` to clean up the allocation. This mirrors the cleanup that `nvif_mem_ctor_map()` did internally (mem.c:36).

**Minor style observation (non-blocking):**

The patch adds `struct drm_device *dev` as a new parameter to `nv50_crc_ctx_init()`, but `dev` is already reachable via the existing `head` parameter as `head->base.base.dev`. The parameter is only used once to replace that chain:

```c
-	struct nv50_core *core = nv50_disp(head->base.base.dev)->core;
+	struct nv50_core *core = nv50_disp(dev)->core;
```

For a stable-targeted bug fix, keeping the change minimal by not adding the parameter would be slightly preferable — just use `head->base.base.dev` as before. That said, it's a trivial cleanup and not worth a respin.

**Reviewed-by worthy:** Yes. The fix is well-motivated, correct, and appropriately scoped.

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Generated by Claude Code Patch Reviewer