On Sat, Aug 31, 2019 at 01:58:16PM +0800, Yunsheng Lin wrote: > According to Section 6.2.14 from ACPI spec 6.3 [1], the setting > of proximity domain is optional, as below: > > This optional object is used to describe proximity domain > associations within a machine. _PXM evaluates to an integer > that identifies a device as belonging to a Proximity Domain > defined in the System Resource Affinity Table (SRAT). That's just words.. what does it actually mean? > This patch checks node id with the below case before returning > node_to_cpumask_map[node]: > 1. if node_id >= nr_node_ids, return cpu_none_mask > 2. if node_id < 0, return cpu_online_mask > 3. if node_to_cpumask_map[node_id] is NULL, return cpu_online_mask > > [1] https://uefi.org/sites/default/files/resources/ACPI_6_3_final_Jan30.pdf > > Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx> > --- > arch/x86/include/asm/topology.h | 6 ++++++ > arch/x86/mm/numa.c | 2 +- > 2 files changed, 7 insertions(+), 1 deletion(-) > > diff --git a/arch/x86/include/asm/topology.h b/arch/x86/include/asm/topology.h > index 4b14d23..f36e9c8 100644 > --- a/arch/x86/include/asm/topology.h > +++ b/arch/x86/include/asm/topology.h > @@ -69,6 +69,12 @@ extern const struct cpumask *cpumask_of_node(int node); > /* Returns a pointer to the cpumask of CPUs on Node 'node'. */ > static inline const struct cpumask *cpumask_of_node(int node) > { > + if (node >= nr_node_ids) > + return cpu_none_mask; > + > + if (node < 0 || !node_to_cpumask_map[node]) > + return cpu_online_mask; > + > return node_to_cpumask_map[node]; > } > #endif I _reallly_ hate this. Users are expected to use valid numa ids. Now we're adding all this checking to all users. Why do we want to do that? Using '(unsigned)node >= nr_nods_ids' is an error. > diff --git a/arch/x86/mm/numa.c b/arch/x86/mm/numa.c > index e6dad60..5e393d2 100644 > --- a/arch/x86/mm/numa.c > +++ b/arch/x86/mm/numa.c > @@ -868,7 +868,7 @@ const struct cpumask *cpumask_of_node(int node) > dump_stack(); > return cpu_none_mask; > } > - if (node_to_cpumask_map[node] == NULL) { > + if (node < 0 || !node_to_cpumask_map[node]) { > printk(KERN_WARNING > "cpumask_of_node(%d): no node_to_cpumask_map!\n", > node); > -- > 2.8.1 >
