On Mon, Apr 9, 2018 at 6:02 PM, Rob Herring <r...@kernel.org> wrote: > On Mon, Apr 9, 2018 at 4:05 PM, Dan Williams <dan.j.willi...@intel.com> wrote: >> On Mon, Apr 9, 2018 at 1:52 PM, Rob Herring <r...@kernel.org> wrote: >>> On Mon, Apr 9, 2018 at 2:46 AM, Oliver O'Halloran <ooh...@gmail.com> wrote: >>>> 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 >>>> CONFIG_NUMA. >>>> >>>> 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. > > You mean the stuff reviewed last week in the middle of the merge > window? Sounds like 4.18 material to me.
It was originally posted for 4.16. The reposting and review came in late this cycle, but outside of a critical issue I'd rather not delay it again. The build error issue is resolved by not allowing modular builds of this driver for now. > > Rob