diff options
| author | Mike Travis <travis@sgi.com> | 2008-06-27 10:10:13 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2008-07-08 13:16:16 +0200 |
| commit | 6a2f47ca27fad36f99e8478a3807d4b8c7db80e7 (patch) | |
| tree | 9d281e3969e5431b1d330cbdc3ee13d626fba4ee | |
| parent | cd5dce2fb023a6f0168344b7dd8adec30017458e (diff) | |
x86: add check for node passed to node_to_cpumask, v3
* When CONFIG_DEBUG_PER_CPU_MAPS is set, the node passed to
node_to_cpumask and node_to_cpumask_ptr should be validated.
If invalid, then a dump_stack is performed and a zero cpumask
is returned.
v2: Slightly different version to remove a compiler warning.
v3: Redone to reflect moving setup.c -> setup_percpu.c
Signed-off-by: Mike Travis <travis@sgi.com>
Cc: Vegard Nossum <vegard.nossum@gmail.com>
Cc: "akpm@linux-foundation.org" <akpm@linux-foundation.org>
Cc: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/setup_percpu.c | 26 | ||||
| -rw-r--r-- | include/asm-x86/topology.h | 7 |
2 files changed, 29 insertions, 4 deletions
diff --git a/arch/x86/kernel/setup_percpu.c b/arch/x86/kernel/setup_percpu.c index 7068f95cccc..43aca2de624 100644 --- a/arch/x86/kernel/setup_percpu.c +++ b/arch/x86/kernel/setup_percpu.c @@ -346,6 +346,10 @@ int early_cpu_to_node(int cpu) return per_cpu(x86_cpu_to_node_map, cpu); } + +/* empty cpumask */ +static const cpumask_t cpu_mask_none; + /* * Returns a pointer to the bitmask of CPUs on Node 'node'. */ @@ -358,13 +362,23 @@ cpumask_t *_node_to_cpumask_ptr(int node) dump_stack(); return &cpu_online_map; } - BUG_ON(node >= nr_node_ids); - return &node_to_cpumask_map[node]; + if (node >= nr_node_ids) { + printk(KERN_WARNING + "_node_to_cpumask_ptr(%d): node > nr_node_ids(%d)\n", + node, nr_node_ids); + dump_stack(); + return (cpumask_t *)&cpu_mask_none; + } + return (cpumask_t *)&node_to_cpumask_map[node]; } EXPORT_SYMBOL(_node_to_cpumask_ptr); /* * Returns a bitmask of CPUs on Node 'node'. + * + * Side note: this function creates the returned cpumask on the stack + * so with a high NR_CPUS count, excessive stack space is used. The + * node_to_cpumask_ptr function should be used whenever possible. */ cpumask_t node_to_cpumask(int node) { @@ -374,7 +388,13 @@ cpumask_t node_to_cpumask(int node) dump_stack(); return cpu_online_map; } - BUG_ON(node >= nr_node_ids); + if (node >= nr_node_ids) { + printk(KERN_WARNING + "node_to_cpumask(%d): node > nr_node_ids(%d)\n", + node, nr_node_ids); + dump_stack(); + return cpu_mask_none; + } return node_to_cpumask_map[node]; } EXPORT_SYMBOL(node_to_cpumask); diff --git a/include/asm-x86/topology.h b/include/asm-x86/topology.h index 1f97758de4a..98e5f17ea85 100644 --- a/include/asm-x86/topology.h +++ b/include/asm-x86/topology.h @@ -57,7 +57,12 @@ static inline int cpu_to_node(int cpu) } #define early_cpu_to_node(cpu) cpu_to_node(cpu) -/* Returns a bitmask of CPUs on Node 'node'. */ +/* Returns a bitmask of CPUs on Node 'node'. + * + * Side note: this function creates the returned cpumask on the stack + * so with a high NR_CPUS count, excessive stack space is used. The + * node_to_cpumask_ptr function should be used whenever possible. + */ static inline cpumask_t node_to_cpumask(int node) { return node_to_cpumask_map[node]; |