arm64/mm: return cpu_all_mask when node is NUMA_NO_NODE

[ Upstream commit a194c5f ]

The @node passed to cpumask_of_node() can be NUMA_NO_NODE, in that
case it will trigger the following WARN_ON(node >= nr_node_ids) due to
mismatched data types of @node and @nr_node_ids. Actually we should
return cpu_all_mask just like most other architectures do if passed
NUMA_NO_NODE.

Also add a similar check to the inline cpumask_of_node() in numa.h.

Signed-off-by: Zhengyuan Liu <liuzhengyuan@tj.kylinos.cn>
Reviewed-by: Gavin Shan <gshan@redhat.com>
Link: https://lore.kernel.org/r/20200921023936.21846-1-liuzhengyuan@tj.kylinos.cn
Signed-off-by: Will Deacon <will@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>

arch/arm64/include/asm/numa.h

@@ -25,6 +25,9 @@ const struct cpumask *cpumask_of_node(int node);
 /* Returns a pointer to the cpumask of CPUs on Node 'node'. */
 static inline const struct cpumask *cpumask_of_node(int node)
 {
+	if (node == NUMA_NO_NODE)
+		return cpu_all_mask;
+
 	return node_to_cpumask_map[node];
 }
 #endif

arch/arm64/mm/numa.c

@@ -46,7 +46,11 @@ EXPORT_SYMBOL(node_to_cpumask_map);
  */
 const struct cpumask *cpumask_of_node(int node)
 {
-	if (WARN_ON(node >= nr_node_ids))
+
+	if (node == NUMA_NO_NODE)
+		return cpu_all_mask;
+
+	if (WARN_ON(node < 0 || node >= nr_node_ids))
 		return cpu_none_mask;
 
 	if (WARN_ON(node_to_cpumask_map[node] == NULL))