On 2016/1/25 18:21, Robert Richter wrote:

On 23.01.16 17:39:20, Hanjun Guo wrote:

quoted

diff --git a/arch/arm64/kernel/acpi_numa.c b/arch/arm64/kernel/acpi_numa.c
new file mode 100644
index 0000000..f7f7533
--- /dev/null
+++ b/arch/arm64/kernel/acpi_numa.c
+/* Callback for parsing of the Proximity Domain <-> Memory Area mappings */
+int __init acpi_numa_memory_affinity_init(struct acpi_srat_mem_affinity *ma)
+{
+	u64 start, end;
+	int node, pxm;
+
+	if (srat_disabled())
+		return -EINVAL;
+
+	if (ma->header.length != sizeof(struct acpi_srat_mem_affinity)) {

Must be:

	ma->header.length < sizeof(struct acpi_srat_mem_affinity)) {

Allow extensions to struct acpi_srat_mem_affinity in newer versions.

Hmm, I think we need to remove the check here now.

There are three cases:

 - firmware ACPI version is consistent with the ACPICA one, then
   ma->header.length == sizeof(struct acpi_srat_mem_affinity )

 - firmware ACPI version is not consistent with the ACPICA one,
   for example, struct acpi_srat_mem_affinity is extended in
   new ACI version, but the formware is using the older one,
  then it's ok to use
  ma->header.length < sizeof(struct acpi_srat_mem_affinity )

 - but if we use the older kernel + updated new firmware,
   then
   ma->header.length > sizeof(struct acpi_srat_mem_affinity )
  will be the case, right?

quoted

+		bad_srat();
+		return -EINVAL;

We need a pr_err() here to avoid that numa setup fails silently due to
bad fw. This applies to all error paths.

See my delta patch below. You can merge it with your patch.

Thanks! I wil merge it into next version.

Hanjun