The patch titled Subject: arm64/mm: add temporary arch_remove_memory() implementation has been added to the -mm tree. Its filename is arm64-mm-add-temporary-arch_remove_memory-implementation.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/arm64-mm-add-temporary-arch_remove_memory-implementation.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/arm64-mm-add-temporary-arch_remove_memory-implementation.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: David Hildenbrand <david@xxxxxxxxxx> Subject: arm64/mm: add temporary arch_remove_memory() implementation A proper arch_remove_memory() implementation is on its way, which also cleanly removes page tables in arch_add_memory() in case something goes wrong. As we want to use arch_remove_memory() in case something goes wrong during memory hotplug after arch_add_memory() finished, let's add a temporary hack that is sufficient enough until we get a proper implementation that cleans up page table entries. We will remove CONFIG_MEMORY_HOTREMOVE around this code in follow up patches. Link: http://lkml.kernel.org/r/20190527111152.16324-5-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: Chintan Pandya <cpandya@xxxxxxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxx> Cc: Jun Yao <yaojun8558363@xxxxxxxxx> Cc: Yu Zhao <yuzhao@xxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: Andrew Banman <andrew.banman@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Arun KS <arunks@xxxxxxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Dave Hansen <dave.hansen@xxxxxxxxxxxxxxx> Cc: "David S. Miller" <davem@xxxxxxxxxxxxx> Cc: Fenghua Yu <fenghua.yu@xxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Heiko Carstens <heiko.carstens@xxxxxxxxxx> Cc: "H. Peter Anvin" <hpa@xxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Martin Schwidefsky <schwidefsky@xxxxxxxxxx> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Cc: Mathieu Malaterre <malat@xxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: "mike.travis@xxxxxxx" <mike.travis@xxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxxx> Cc: Oscar Salvador <osalvador@xxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Cc: Pavel Tatashin <pavel.tatashin@xxxxxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Rob Herring <robh@xxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Wei Yang <richard.weiyang@xxxxxxxxx> Cc: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- arch/arm64/mm/mmu.c | 19 +++++++++++++++++++ 1 file changed, 19 insertions(+) --- a/arch/arm64/mm/mmu.c~arm64-mm-add-temporary-arch_remove_memory-implementation +++ a/arch/arm64/mm/mmu.c @@ -1084,4 +1084,23 @@ int arch_add_memory(int nid, u64 start, return __add_pages(nid, start >> PAGE_SHIFT, size >> PAGE_SHIFT, restrictions); } +#ifdef CONFIG_MEMORY_HOTREMOVE +void arch_remove_memory(int nid, u64 start, u64 size, + struct vmem_altmap *altmap) +{ + unsigned long start_pfn = start >> PAGE_SHIFT; + unsigned long nr_pages = size >> PAGE_SHIFT; + struct zone *zone; + + /* + * FIXME: Cleanup page tables (also in arch_add_memory() in case + * adding fails). Until then, this function should only be used + * during memory hotplug (adding memory), not for memory + * unplug. ARCH_ENABLE_MEMORY_HOTREMOVE must not be + * unlocked yet. + */ + zone = page_zone(pfn_to_page(start_pfn)); + __remove_pages(zone, start_pfn, nr_pages, altmap); +} +#endif #endif _ Patches currently in -mm which might be from david@xxxxxxxxxx are mm-memory_hotplug-simplify-and-fix-check_hotplug_memory_range.patch s390x-mm-fail-when-an-altmap-is-used-for-arch_add_memory.patch s390x-mm-implement-arch_remove_memory.patch arm64-mm-add-temporary-arch_remove_memory-implementation.patch drivers-base-memory-pass-a-block_id-to-init_memory_block.patch mm-memory_hotplug-allow-arch_remove_pages-without-config_memory_hotremove.patch mm-memory_hotplug-create-memory-block-devices-after-arch_add_memory.patch mm-memory_hotplug-drop-mhp_memblock_api.patch mm-memory_hotplug-remove-memory-block-devices-before-arch_remove_memory.patch mm-memory_hotplug-make-unregister_memory_block_under_nodes-never-fail.patch mm-memory_hotplug-remove-zone-parameter-from-sparse_remove_one_section.patch