[PATCH] nvme-multipath: fix flex array size in struct nvme_ns_head

[Keith Busch]

On Wed, May 27, 2026 at 11:50:00AM +0530, Nilay Shroff wrote:
> Fix this by allocating the flexible array using nr_node_ids instead
> of num_possible_nodes(). Since nr_node_ids represents the maximum
> possible NUMA node IDs, indexing current_path[] using numa_node_id()
> becomes safe even on systems with sparse node IDs.

What is the largest nr_node_ids we can reasonably expect to see? I don't
want to end up trying to allocate a billion entry sparse array just to
index a tiny fraction of them. Not that we didn't have a similar problem
before, but this patch makes it clear we haven't been checking.