On Mon, Apr 9, 2018 at 4:05 PM, Dan Williams <dan.j.williams(a)intel.com> wrote:
On Mon, Apr 9, 2018 at 1:52 PM, Rob Herring <robh(a)kernel.org>
> On Mon, Apr 9, 2018 at 2:46 AM, Oliver O'Halloran <oohall(a)gmail.com>
>> Some OF platforms (pseries and some SPARC systems) has their own
>> implementations of NUMA affinity detection rather than using the generic
>> OF_NUMA driver, which mainly exists for arm64. For other platforms one
>> of two fallbacks provided by the base OF driver are used depending on
>> In the CONFIG_NUMA=n case the fallback is an inline function in of.h.
>> In the =y case the fallback is a real function which is defined as a
>> weak symbol so that it may be overwritten by the architecture if desired.
>> The problem with this arrangement is that the real implementations all
>> export of_node_to_nid(). Unfortunately it's not possible to export the
>> fallback since it would clash with the non-weak version. As a result
>> we get build failures when:
>> a) CONFIG_NUMA=y && CONFIG_OF=y, and
>> b) The platform doesn't implement of_node_to_nid(), and
>> c) A module uses of_node_to_nid()
>> Given b) will be true for most platforms this is fairly easy to hit
>> and has been observed on ia64 and x86.
> How specifically do we hit this? The only module I see using
> of_node_to_nid in mainline is Cell EDAC driver.
The of_pmem driver is using it currently pending for a 4.17 pull
request. Stephen hit the compile failure in -next.
I took a look at this. The correct fix here is to use dev_to_node() instead:
diff --git a/drivers/nvdimm/of_pmem.c b/drivers/nvdimm/of_pmem.c
index 85013bad35de..0a701837dfc0 100644
@@ -67,7 +67,7 @@ static int of_pmem_region_probe(struct platform_device *pdev)
memset(&ndr_desc, 0, sizeof(ndr_desc));
ndr_desc.attr_groups = region_attr_groups;
- ndr_desc.numa_node = of_node_to_nid(np);
+ ndr_desc.numa_node = dev_to_node(&pdev->dev);
ndr_desc.res = &pdev->resource[i];
ndr_desc.of_node = np;
And we should remove the exported symbol.
I'll send a proper patch.