2010-01-06 06:11:36

by Anton Blanchard

Subject: [patch 5/6] sparc: cpumask_of_node() should handle -1 as a node

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 <[email protected]>
---

Index: linux-cpumask/arch/sparc/include/asm/topology_64.h
===================================================================
--- linux-cpumask.orig/arch/sparc/include/asm/topology_64.h 2010-01-06 15:20:22.912584116 +1100
+++ linux-cpumask/arch/sparc/include/asm/topology_64.h 2010-01-06 15:27:17.209419879 +1100
@@ -12,7 +12,9 @@ static inline int cpu_to_node(int cpu)

#define parent_node(node) (node)

-#define cpumask_of_node(node) (&numa_cpumask_lookup_table[node])
+#define cpumask_of_node(node) ((node) == -1 ? \
+ cpu_all_mask : \
+ &numa_cpumask_lookup_table[node])

struct pci_bus;
#ifdef CONFIG_PCI

--

2010-01-07 04:22:24

by David Miller

Subject: Re: [patch 5/6] sparc: cpumask_of_node() should handle -1 as a node

From: Anton Blanchard <[email protected]>
Date: Wed, 06 Jan 2010 15:55:14 +1100

> 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 <[email protected]>

Acked-by: David S. Miller <[email protected]>