[PATCH] hw/arm/boot: Use NUMA node ID in memory node name

[Gavin Shan]

We possibly populate empty nodes where memory isn't included and might
be hot added at late time. The FDT memory nodes can't be created due
to conflicts on their names if multiple empty nodes are specified.
For example, the VM fails to start with the following error messages.

  /home/gavin/sandbox/qemu.main/build/qemu-system-aarch64          \
  -accel kvm -machine virt,gic-version=host                        \
  -cpu host -smp 4,sockets=2,cores=2,threads=1 -m 1024M,maxmem=64G \
  -object memory-backend-ram,id=mem0,size=512M                     \
  -object memory-backend-ram,id=mem1,size=512M                     \
  -numa node,nodeid=0,cpus=0-1,memdev=mem0                         \
  -numa node,nodeid=1,cpus=2-3,memdev=mem1                         \
  -numa node,nodeid=2                                              \
  -numa node,nodeid=3                                              \
    :
  -device virtio-balloon-pci,id=balloon0,free-page-reporting=yes

  qemu-system-aarch64: FDT: Failed to create subnode /memory@80000000: \
                       FDT_ERR_EXISTS

This fixes the issue by using NUMA node ID or zero in the memory node
name to avoid the conflicting memory node names. With this applied, the
VM can boot successfully with above command lines.

Signed-off-by: Gavin Shan <gshan@redhat.com>
---
 hw/arm/boot.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/hw/arm/boot.c b/hw/arm/boot.c
index d7b059225e..3169bdf595 100644
--- a/hw/arm/boot.c
+++ b/hw/arm/boot.c
@@ -432,7 +432,12 @@ static int fdt_add_memory_node(void *fdt, uint32_t acells, 
hwaddr mem_base,
     char *nodename;
     int ret;
 
-    nodename = g_strdup_printf("/memory@%" PRIx64, mem_base);
+    if (numa_node_id >= 0) {
+        nodename = g_strdup_printf("/memory@%d", numa_node_id);
+    } else {
+        nodename = g_strdup("/memory@0");
+    }
+
     qemu_fdt_add_subnode(fdt, nodename);
     qemu_fdt_setprop_string(fdt, nodename, "device_type", "memory");
     ret = qemu_fdt_setprop_sized_cells(fdt, nodename, "reg", acells, mem_base,
-- 
2.23.0