Capacity is stranded when CFMWS regions are not aligned to block size.
On x86, block size increases with capacity (2G blocks @ 64G capacity).
Use CFMWS base/size to report memory block size alignment advice.
Suggested-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Signed-off-by: Gregory Price <gourry@xxxxxxxxxx>
Acked-by: Mike Rapoport (Microsoft) <rppt@xxxxxxxxxx>
Acked-by: David Hildenbrand <david@xxxxxxxxxx>
Acked-by: Dan Williams <dan.j.williams@xxxxxxxxx>
Tested-by: Fan Ni <fan.ni@xxxxxxxxxxx>
---
drivers/acpi/numa/srat.c | 12 +++++++++++-
1 file changed, 11 insertions(+), 1 deletion(-)
diff --git a/drivers/acpi/numa/srat.c b/drivers/acpi/numa/srat.c
index bec0dcd1f9c3..af7d51222933 100644
--- a/drivers/acpi/numa/srat.c
+++ b/drivers/acpi/numa/srat.c
@@ -14,6 +14,7 @@
#include <linux/errno.h>
#include <linux/acpi.h>
#include <linux/memblock.h>
+#include <linux/memory.h>
#include <linux/numa.h>
#include <linux/nodemask.h>
#include <linux/topology.h>
@@ -339,13 +340,22 @@ static int __init acpi_parse_cfmws(union acpi_subtable_headers *header,
{
struct acpi_cedt_cfmws *cfmws;
int *fake_pxm = arg;
- u64 start, end;
+ u64 start, end, align;
int node;
cfmws = (struct acpi_cedt_cfmws *)header;
start = cfmws->base_hpa;
end = cfmws->base_hpa + cfmws->window_size;
+ /* Align memblock size to CFMW regions if possible */
+ align = 1UL << __ffs(start | end);
+ if (align >= SZ_256M) {
+ if (memory_block_advise_max_size(align) < 0)
+ pr_warn("CFMWS: memblock size advise failed\n");
+ } else {
+ pr_err("CFMWS: [BIOS BUG] base/size alignment violates spec\n");
+ }
+
/*
* The SRAT may have already described NUMA details for all,
* or a portion of, this CFMWS HPA range. Extend the memblks
--
2.43.0
