On Mon, Jun 18, 2018 at 11:05 PM, Dan Williams <dan.j.williams@xxxxxxxxx> wrote: > The routines hmm_devmem_add(), and hmm_devmem_add_resource() are > now wrappers around the functionality provided by devm_memremap_pages() to > inject a dev_pagemap instance and hook page-idle events. The > devm_memremap_pages() interface is base infrastructure for HMM which has > more and deeper ties into the kernel memory management implementation > than base ZONE_DEVICE. > > Originally, the HMM page structure creation routines copied the > devm_memremap_pages() code and reused ZONE_DEVICE. A cleanup to unify > the implementations was discussed during the initial review: > http://lkml.iu.edu/hypermail/linux/kernel/1701.2/00812.html > > Given that devm_memremap_pages() is marked EXPORT_SYMBOL_GPL by its > authors and the hmm_devmem_{add,add_resource} routines are simple > wrappers around that base, mark these routines as EXPORT_SYMBOL_GPL as > well. > > Cc: "Jérôme Glisse" <jglisse@xxxxxxxxxx> > Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx> > Reviewed-by: Christoph Hellwig <hch@xxxxxx> > Signed-off-by: Dan Williams <dan.j.williams@xxxxxxxxx> Currently OpenAFS is blocked from compiling with the 4.18 series due to the current state of put_page() inadvertently pulling in GPL-only symbols. This series, "PATCH v3 0/8] mm: Rework hmm to use devm_memremap_pages and other fixes" corrects that situation and corrects HMM's usage of EXPORT_SYMBOL_GPL. If HMM wants to export functionality to out-of-tree proprietary drivers it should do so without consuming GPL-only exports, or consuming internal-only public functions in its exports. In addition to duplicating devm_memremap_pages(), that should have been EXPORT_SYMBOL_GPL from the beginning, it is also exporting / consuming these GPL-only symbols via HMM's EXPORT_SYMBOL entry points. mmu_notifier_unregister_no_release percpu_ref region_intersects __class_create Those entry points also consume / export functionality that is currently not exported to any other driver. alloc_pages_vma walk_page_range Andrew, please consider applying this v3 series to fix this up (let me know if you need a resend).
