NVDIMMs can belong to their own proximity domains, as described by the
NFIT. In such cases, the SRAT needs to have Memory Affinity structures
in the SRAT for these NVDIMMs, otherwise Linux doesn't populate node
data structures properly during NUMA initialization. See the following
for an example failure case.

https://lore.kernel.org/linux-nvdimm/20200416225438.15208-1-vishal.l.verma@intel.com/

Fix this by adding device address range and node information from
NVDIMMs to the SRAT in build_srat().

The relevant command line options to exercise this are below. Nodes 0-1
contain CPUs and regular memory, and nodes 2-3 are the NVDIMM address
space.

  -numa node,nodeid=0,mem=2048M,
  -numa node,nodeid=1,mem=2048M,
  -numa node,nodeid=2,mem=0,
  -object memory-backend-file,id=nvmem0,share,mem-path=nvdimm-0,size=16384M,align=128M
  -device nvdimm,memdev=nvmem0,id=nv0,label-size=2M,node=2
  -numa node,nodeid=3,mem=0,
  -object memory-backend-file,id=nvmem1,share,mem-path=nvdimm-1,size=16384M,align=128M
  -device nvdimm,memdev=nvmem1,id=nv1,label-size=2M,node=3

Cc: Jingqi Liu <jingqi.liu@intel.com>
Cc: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Vishal Verma <vishal.l.verma@intel.com>
---
 hw/i386/acpi-build.c | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index 23c77eeb95..b0da67de0e 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -48,6 +48,7 @@
 #include "migration/vmstate.h"
 #include "hw/mem/memory-device.h"
 #include "hw/mem/nvdimm.h"
+#include "qemu/nvdimm-utils.h"
 #include "sysemu/numa.h"
 #include "sysemu/reset.h"
 
@@ -2429,6 +2430,25 @@ build_srat(GArray *table_data, BIOSLinker *linker, MachineState *machine)
                               MEM_AFFINITY_ENABLED);
         }
     }
+
+    if (machine->nvdimms_state->is_enabled) {
+        GSList *device_list = nvdimm_get_device_list();
+
+        for (; device_list; device_list = device_list->next) {
+            DeviceState *dev = device_list->data;
+            int node = object_property_get_int(OBJECT(dev), PC_DIMM_NODE_PROP,
+                                               NULL);
+            uint64_t addr = object_property_get_uint(OBJECT(dev),
+                                                     PC_DIMM_ADDR_PROP, NULL);
+            uint64_t size = object_property_get_uint(OBJECT(dev),
+                                                     PC_DIMM_SIZE_PROP, NULL);
+
+            numamem = acpi_data_push(table_data, sizeof *numamem);
+            build_srat_memory(numamem, addr, size, node,
+                              MEM_AFFINITY_ENABLED | MEM_AFFINITY_NON_VOLATILE);
+        }
+    }
+

Looks good for me.
Reviewed-by: Jingqi Liu <jingqi.liu@intel.com>

Thanks,
Jingqi

     slots = (table_data->len - numa_start) / sizeof *numamem;
     for (; slots < pcms->numa_nodes + 2; slots++) {
         numamem = acpi_data_push(table_data, sizeof *numamem);