Messages in this thread Patch in this message | | | Date | Mon, 14 Feb 2011 13:55:30 GMT | From | tip-bot for David Rientjes <> | Subject | [tip:x86/numa] x86, numa: Add error handling for bad cpu-to-node mappings |
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Commit-ID: 14392fd329eca9b59d51c0aa5d0acfb4965424d1 Gitweb: http://git.kernel.org/tip/14392fd329eca9b59d51c0aa5d0acfb4965424d1 Author: David Rientjes <rientjes@google.com> AuthorDate: Mon, 7 Feb 2011 14:08:53 -0800 Committer: Ingo Molnar <mingo@elte.hu> CommitDate: Mon, 14 Feb 2011 13:29:27 +0100
x86, numa: Add error handling for bad cpu-to-node mappings
CONFIG_DEBUG_PER_CPU_MAPS may return NUMA_NO_NODE when an early_cpu_to_node() mapping hasn't been initialized. In such a case, it emits a warning and continues without an issue but callers may try to use the return value to index into an array.
We can catch those errors and fail silently since a warning has already been emitted. No current user of numa_add_cpu() requires this error checking to avoid a crash, but it's better to be proactive in case a future user happens to have a bug and a user tries to diagnose it with CONFIG_DEBUG_PER_CPU_MAPS.
Reported-by: Jesper Juhl <jj@chaosbits.net> Signed-off-by: David Rientjes <rientjes@google.com> Cc: Tejun Heo <tj@kernel.org> LKML-Reference: <alpine.DEB.2.00.1102071407250.7812@chino.kir.corp.google.com> Signed-off-by: Ingo Molnar <mingo@elte.hu> --- arch/x86/mm/numa.c | 4 ++++ arch/x86/mm/numa_64.c | 4 ++++ 2 files changed, 8 insertions(+), 0 deletions(-)
diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c index bf60715..9559d36 100644 --- a/arch/x86/mm/numa.c +++ b/arch/x86/mm/numa.c @@ -219,6 +219,10 @@ struct cpumask __cpuinit *debug_cpumask_set_cpu(int cpu, int enable) struct cpumask *mask; char buf[64]; + if (node == NUMA_NO_NODE) { + /* early_cpu_to_node() already emits a warning and trace */ + return NULL; + } mask = node_to_cpumask_map[node]; if (!mask) { pr_err("node_to_cpumask_map[%i] NULL\n", node); diff --git a/arch/x86/mm/numa_64.c b/arch/x86/mm/numa_64.c index f548fbf..3f9411e 100644 --- a/arch/x86/mm/numa_64.c +++ b/arch/x86/mm/numa_64.c @@ -709,6 +709,10 @@ static void __cpuinit numa_set_cpumask(int cpu, int enable) struct cpumask *mask; int i; + if (node == NUMA_NO_NODE) { + /* early_cpu_to_node() already emits a warning and trace */ + return; + } for_each_online_node(i) { unsigned long addr;
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