On Thu, Feb 29, 2024 at 04:25:44PM +0000, Jonathan Cameron wrote:
> If qemu is started with a proximity node containing CPUs alone,
> it will provide one of these structures to say memory in this
> node is directly connected to itself.
>
> This description is arguably pointless even if there is memory
> in the node. If there is no memory present, and hence no SRAT
> entry it breaks Linux HMAT passing and the table is rejected.
>
> https://elixir.bootlin.com/linux/latest/source/drivers/acpi/numa/hmat.c#L444
>
Nit: This link becomes out of date pretty much immediately, consider
using a versioned link.
> Signed-off-by: Jonathan Cameron <jonathan.came...@huawei.com>
> ---
> hw/acpi/hmat.c | 7 +++++++
> 1 file changed, 7 insertions(+)
>
> diff --git a/hw/acpi/hmat.c b/hw/acpi/hmat.c
> index 3042d223c8..723ae28d32 100644
> --- a/hw/acpi/hmat.c
> +++ b/hw/acpi/hmat.c
> @@ -204,6 +204,13 @@ static void hmat_build_table_structs(GArray *table_data,
> NumaState *numa_state)
> build_append_int_noprefix(table_data, 0, 4); /* Reserved */
>
> for (i = 0; i < numa_state->num_nodes; i++) {
> + /*
> + * Linux rejects whole HMAT table if a node with no memory
> + * has one of these structures listing it as a target.
> + */
> + if (!numa_state->nodes[i].node_mem) {
> + continue;
> + }
> flags = 0;
>
> if (numa_state->nodes[i].initiator < MAX_NODES) {
> --
> 2.39.2
>
>
