Re: [libvirt] [Qemu-devel] [PATCH V17 02/11] NUMA: check if the total numa memory size is equal to ram_size
CCing libvir-list.
On Wed, Dec 04, 2013 at 03:58:50PM +0800, Wanlong Gao wrote:
If the total number of the assigned numa nodes memory is not
equal to the assigned ram size, it will write the wrong data
to ACPI talb, then the guest will ignore the wrong ACPI table
and recognize all memory to one node. It's buggy, we should
check it to ensure that we write the right data to ACPI table.
Signed-off-by: Wanlong Gao <gaowanlong(a)cn.fujitsu.com>
This will make configurations that could be running for years (except
that the guest OS was ignoring the NUMA data) suddenly stop running. I
just want to confirm: we really want that, right?
Does libvirt allow this kind of broken configuration to be generated, or
it already ensures the total NUMA node sizes match RAM size?
---
numa.c | 10 ++++++++++
1 file changed, 10 insertions(+)
diff --git a/numa.c b/numa.c
index ce7736a..beda80e 100644
--- a/numa.c
+++ b/numa.c
@@ -150,6 +150,16 @@ void set_numa_nodes(void)
node_mem[i] = ram_size - usedmem;
}
+ uint64_t numa_total = 0;
+ for (i = 0; i < nb_numa_nodes; i++) {
+ numa_total += node_mem[i];
+ }
+ if (numa_total != ram_size) {
+ fprintf(stderr, "qemu: numa nodes total memory size "
+ "should equal to ram_size\n");
+ exit(1);
+ }
+
for (i = 0; i < nb_numa_nodes; i++) {
if (!bitmap_empty(node_cpumask[i], MAX_CPUMASK_BITS)) {
break;
--
1.8.5
--
Eduardo