[patch 3/6] ia64: cpumask_of_node() should handle -1 as a node

Anton Blanchard
2010-01-06T06:11:13Z

pcibus_to_node can return -1 if we cannot determine which node a pci bus
is on. If passed -1, cpumask_of_node will negatively index the lookup array
and pull in random data:

# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpus
00000000,00000003,00000000,00000000
# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpulist
64-65

Change cpumask_of_node to check for -1 and return cpu_all_mask in this
case:

# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpus
ffffffff,ffffffff,ffffffff,ffffffff
# cat /sys/devices/pci0000:00/0000:00:01.0/local_cpulist
0-127

Signed-off-by: Anton Blanchard <anton@samba.org>
---

Index: linux-cpumask/arch/ia64/include/asm/topology.h
===================================================================
--- linux-cpumask.orig/arch/ia64/include/asm/topology.h 2010-01-06 15:20:22.832584260 +1100
+++ linux-cpumask/arch/ia64/include/asm/topology.h 2010-01-06 15:26:46.620650121 +1100
@@ -33,7 +33,9 @@
/*
* Returns a bitmask of CPUs on Node 'node'.
*/
-#define cpumask_of_node(node) (&node_to_cpu_mask[node])
+#define cpumask_of_node(node) ((node) == -1 ? \
+ cpu_all_mask : \
+ &node_to_cpu_mask[node])

/*
* Returns the number of the node containing Node 'nid'.

--