memblock: allow zero threshold in validate_numa_converage()

BugLink: https://bugs.launchpad.net/bugs/2096827

commit 9cdc642 upstream.

Currently memblock validate_numa_converage() returns false negative when
threshold set to zero.

Make the check if the memory size with invalid node ID is greater than
the threshold exclusive to fix that.

Link: https://lore.kernel.org/all/[email protected]/
Signed-off-by: Mike Rapoport (Microsoft) <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
Signed-off-by: Koichiro Den <[email protected]>

Author: rppt

mm/memblock.c

@@ -735,7 +735,7 @@ int __init_memblock memblock_add(phys_addr_t base, phys_addr_t size)
 /**
  * memblock_validate_numa_coverage - check if amount of memory with
  * no node ID assigned is less than a threshold
- * @threshold_bytes: maximal number of pages that can have unassigned node
+ * @threshold_bytes: maximal memory size that can have unassigned node
  * ID (in bytes).
  *
  * A buggy firmware may report memory that does not belong to any node.
@@ -755,7 +755,7 @@ bool __init_memblock memblock_validate_numa_coverage(unsigned long threshold_byt
 			nr_pages += end_pfn - start_pfn;
 	}
 
-	if ((nr_pages << PAGE_SHIFT) >= threshold_bytes) {
+	if ((nr_pages << PAGE_SHIFT) > threshold_bytes) {
 		mem_size_mb = memblock_phys_mem_size() >> 20;
 		pr_err("NUMA: no nodes coverage for %luMB of %luMB RAM\n",
 		       (nr_pages << PAGE_SHIFT) >> 20, mem_size_mb);