[ adding Andrew, Christoph, and linux-mm ] On Wed, Jun 13, 2018 at 12:33 PM, Joe Gorse <jhgorse@xxxxxxxxx> wrote: > Greetings, > > Please CC answers & comments to this email. Thanks! =) > > Our build is breaking as of > commit e7638488434415aa478e78435cac8f0365737638 > Author: Dan Williams <dan.j.williams@xxxxxxxxx> > Date: Wed May 16 11:46:08 2018 -0700 > > mm: introduce MEMORY_DEVICE_FS_DAX and CONFIG_DEV_PAGEMAP_OPS > ... snip ... > https://patchwork.kernel.org/patch/10412459/ > > We do not directly use the GPL-only symbol '__put_devmap_managed_page'. It > appears to be picked up from static-inlining in put_page(), which we need. > > How shall we proceed? Would it be reasonable to request the change of the > GPL-only exports for this commit? > > Cheers, > Joe Gorse > > P.S. The build failure, for the morbidly curious: >> FATAL: modpost: GPL-incompatible module libafs.ko uses GPL-only symbol >> '__put_devmap_managed_page' >> scripts/Makefile.modpost:92: recipe for target '__modpost' failed >> make[6]: *** [__modpost] Error 1 I think the right answer here is to make __put_devmap_managed_page() EXPORT_SYMBOL(), since features like devm_memremap_pages() want to change the behavior of all users of put_page(). It again holds that devm_memremap_pages() needs to become EXPORT_SYMBOL_GPL() because it, not put_page(), is the interface that is leaking control of core kernel state/infrastructure to its users.
