x86/uv: fix init of memory-less nodes

Add support for nodes that have cpus but no memory.
The current code was failing to add these nodes
to the nodes_present_map.

v2: Fixes case caught by David Rientjes - missed support
    for the x2apic SRAT table.

[ Impact: fix potential boot crash on memory-less UV nodes. ]

Reported-by: David Rientjes <rientjes@google.com>
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20090417142242.GA23743@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

1 files changed, 5 insertions, 1 deletions

diff --git a/arch/x86/mm/srat_64.c b/arch/x86/mm/srat_64.c
index c7d272b8574..33c5fa57e43 100644
--- a/arch/x86/mm/srat_64.c
+++ b/arch/x86/mm/srat_64.c
@@ -28,6 +28,7 @@ int acpi_numa __initdata;
 static struct acpi_table_slit *acpi_slit;
 
 static nodemask_t nodes_parsed __initdata;
+static nodemask_t cpu_nodes_parsed __initdata;
 static struct bootnode nodes[MAX_NUMNODES] __initdata;
 static struct bootnode nodes_add[MAX_NUMNODES];
 static int found_add_area __initdata;
@@ -141,6 +142,7 @@ acpi_numa_x2apic_affinity_init(struct acpi_srat_x2apic_cpu_affinity *pa)
 
         apic_id = pa->apic_id;
         apicid_to_node[apic_id] = node;
+        node_set(node, cpu_nodes_parsed);
         acpi_numa = 1;
         printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
                pxm, apic_id, node);
@@ -174,6 +176,7 @@ acpi_numa_processor_affinity_init(struct acpi_srat_cpu_affinity *pa)
         else
                 apic_id = pa->apic_id;
         apicid_to_node[apic_id] = node;
+        node_set(node, cpu_nodes_parsed);
         acpi_numa = 1;
         printk(KERN_INFO "SRAT: PXM %u -> APIC %u -> Node %u\n",
                pxm, apic_id, node);
@@ -402,7 +405,8 @@ int __init acpi_scan_nodes(unsigned long start, unsigned long end)
                 return -1;
         }
 
-        node_possible_map = nodes_parsed;
+        /* Account for nodes with cpus and no memory */
+        nodes_or(node_possible_map, nodes_parsed, cpu_nodes_parsed);
 
         /* Finally register nodes */
         for_each_node_mask(i, node_possible_map)