Re: [PATCH v3 3/5] arm64/numa: add nid check for memory block

From: Leizhen (ThunderTown)
Date: Sun Jun 05 2016 - 21:47:48 EST


On 2016/6/3 17:52, Will Deacon wrote:
> On Thu, Jun 02, 2016 at 10:28:09AM +0800, Zhen Lei wrote:
>> Use the same tactic to cpu and numa-distance nodes.
>
> Sorry, I don't understand... :/

In function of_numa_parse_cpu_nodes:
for_each_child_of_node(cpus, np) {
...
r = of_property_read_u32(np, "numa-node-id", &nid);
...
if (nid >= MAX_NUMNODES) //check nid
pr_warn("NUMA: Node id %u exceeds maximum value\n", nid); //print warning info
...


In function numa_set_distance:
if (from >= numa_distance_cnt || to >= numa_distance_cnt || //check nid
from < 0 || to < 0) {
pr_warn_once("NUMA: Warning: node ids are out of bound, from=%d to=%d distance=%d\n", //print warning info
from, to, distance);
return;
}

Both these two functions will check that whether nid(configured in dts, the subnodes of
cpus and distance-map) is right or not. So memory@ should also be checked.


memory@c00000 {
device_type = "memory";
reg = <0x0 0xc00000 0x0 0x80000000>;
/* node 0 */
numa-node-id = <0>; //have not been checked yet.
}; //suppose I configued a wrong nid, it will not print any warning info

cpus {
#address-cells = <2>;
#size-cells = <0>;

cpu@0 {
device_type = "cpu";
compatible = "arm,armv8";
reg = <0x0 0x0>;
enable-method = "psci";
/* node 0 */
numa-node-id = <0>; //checked in of_numa_parse_cpu_nodes
};

distance-map {
compatible = "numa-distance-map-v1";
distance-matrix = <0 0 10>, //checked in of_numa_parse_distance_map_v1 --> numa_set_distance
<0 1 20>,
<1 1 10>;
};

>
> Will
>
>>
>> Signed-off-by: Zhen Lei <thunder.leizhen@xxxxxxxxxx>
>> ---
>> arch/arm64/mm/numa.c | 5 +++++
>> 1 file changed, 5 insertions(+)
>>
>> diff --git a/arch/arm64/mm/numa.c b/arch/arm64/mm/numa.c
>> index c7fe3ec..2601660 100644
>> --- a/arch/arm64/mm/numa.c
>> +++ b/arch/arm64/mm/numa.c
>> @@ -141,6 +141,11 @@ int __init numa_add_memblk(int nid, u64 start, u64 end)
>> {
>> int ret;
>>
>> + if (nid >= MAX_NUMNODES) {
>> + pr_warn("NUMA: Node id %u exceeds maximum value\n", nid);
>> + return -EINVAL;
>> + }
>> +
>> ret = memblock_set_node(start, (end - start), &memblock.memory, nid);
>> if (ret < 0) {
>> pr_err("NUMA: memblock [0x%llx - 0x%llx] failed to add on node %d\n",
>> --
>> 2.5.0
>>
>>
>
> .
>