For reasons unknown, Windows won't online all memory, both at command
line and hot-plugged later, unless the hotplug mem hole SRAT entry
specifies a node greater or equal to the ones where memory is added.
Using the highest node on the machine makes recent versions of Windows
happy.
With this example command line:
... \
-m 1024,slots=4,maxmem=32G \
-numa node,nodeid=0 \
-numa node,nodeid=1 \
-numa node,nodeid=2 \
-numa node,nodeid=3 \
-object memory-backend-ram,size=1G,id=mem-mem1 \
-device pc-dimm,id=dimm-mem1,memdev=mem-mem1,node=1
Windows reports a total of 1G of RAM without this commit and the expected
2G with this commit.
Signed-off-by: Ladi Prosek <lpro...@redhat.com>
---
hw/i386/acpi-build.c | 7 +++++--
1 file changed, 5 insertions(+), 2 deletions(-)
diff --git a/hw/i386/acpi-build.c b/hw/i386/acpi-build.c
index afcadac..9653583 100644
--- a/hw/i386/acpi-build.c
+++ b/hw/i386/acpi-build.c
@@ -2404,14 +2404,17 @@ build_srat(GArray *table_data, BIOSLinker *linker,
MachineState *machine)
}
/*
- * Entry is required for Windows to enable memory hotplug in OS.
+ * Entry is required for Windows to enable memory hotplug in OS
+ * and for Linux to enable SWIOTLB even if booted with less than
+ * 4G of RAM. Windows works better if the entry sets proximity
+ * to the highest NUMA node in the machine.
* Memory devices may override proximity set by this entry,
* providing _PXM method if necessary.
*/
if (hotplugabble_address_space_size) {
numamem = acpi_data_push(table_data, sizeof *numamem);
build_srat_memory(numamem, pcms->hotplug_memory.base,
- hotplugabble_address_space_size, 0,
+ hotplugabble_address_space_size, pcms->numa_nodes -
1,
MEM_AFFINITY_HOTPLUGGABLE | MEM_AFFINITY_ENABLED);
}
--
2.9.3
