[PATCH v10 4/6] ACPI: HMAT: Fix handling of changes from ACPI 6.2 to ACPI 6.3

Jonathan Cameron Jonathan.Cameron at huawei.com
Mon Sep 7 10:03:05 EDT 2020


In ACPI 6.3, the Memory Proximity Domain Attributes Structure
changed substantially.  One of those changes was that the flag
for "Memory Proximity Domain field is valid" was deprecated.

This was because the field "Proximity Domain for the Memory"
became a required field and hence having a validity flag makes
no sense.

So the correct logic is to always assume the field is there.
Current code assumes it never is.

Signed-off-by: Jonathan Cameron <Jonathan.Cameron at huawei.com>
---
Changes for v10:
 * Reorder the checks so we confirm the version first before taking the
  ACPI_HMAT_MEMORY_PD_VALID into account.
  (Bjorn Helgaas)

 drivers/acpi/numa/hmat.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/acpi/numa/hmat.c b/drivers/acpi/numa/hmat.c
index 2c32cfb72370..6a91a55229ae 100644
--- a/drivers/acpi/numa/hmat.c
+++ b/drivers/acpi/numa/hmat.c
@@ -424,7 +424,8 @@ static int __init hmat_parse_proximity_domain(union acpi_subtable_headers *heade
 		pr_info("HMAT: Memory Flags:%04x Processor Domain:%u Memory Domain:%u\n",
 			p->flags, p->processor_PD, p->memory_PD);
 
-	if (p->flags & ACPI_HMAT_MEMORY_PD_VALID && hmat_revision == 1) {
+	if ((hmat_revision == 1 && p->flags & ACPI_HMAT_MEMORY_PD_VALID) ||
+	    hmat_revision > 1) {
 		target = find_mem_target(p->memory_PD);
 		if (!target) {
 			pr_debug("HMAT: Memory Domain missing from SRAT\n");
-- 
2.19.1




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