From: David Hildenbrand <david@xxxxxxxxxx> Subject: mm/memory_hotplug: simplify and fix check_hotplug_memory_range() Patch series "mm/memory_hotplug: Factor out memory block devicehandling", v3. We only want memory block devices for memory to be onlined/offlined (add/remove from the buddy). This is required so user space can online/offline memory and kdump gets notified about newly onlined memory. Let's factor out creation/removal of memory block devices. This helps to further cleanup arch_add_memory/arch_remove_memory() and to make implementation of new features easier - especially sub-section memory hot add from Dan. Anshuman Khandual is currently working on arch_remove_memory(). I added a temporary solution via "arm64/mm: Add temporary arch_remove_memory() implementation", that is sufficient as a firsts tep in the context of this series. (we don't cleanup page tables in case anything goes wrong already) Did a quick sanity test with DIMM plug/unplug, making sure all devices and sysfs links properly get added/removed. Compile tested on s390x and x86-64. This patch (of 11): By converting start and size to page granularity, we actually ignore unaligned parts within a page instead of properly bailing out with an error. Link: http://lkml.kernel.org/r/20190527111152.16324-2-david@xxxxxxxxxx Signed-off-by: David Hildenbrand <david@xxxxxxxxxx> Reviewed-by: Dan Williams <dan.j.williams@xxxxxxxxx> Reviewed-by: Wei Yang <richardw.yang@xxxxxxxxxxxxxxx> Reviewed-by: Pavel Tatashin <pasha.tatashin@xxxxxxxxxx> Reviewed-by: Oscar Salvador <osalvador@xxxxxxx> Acked-by: Michal Hocko <mhocko@xxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Qian Cai <cai@xxxxxx> Cc: Arun KS <arunks@xxxxxxxxxxxxxx> Cc: Mathieu Malaterre <malat@xxxxxxxxxx> Cc: Alex Deucher <alexander.deucher@xxxxxxx> Cc: Andrew Banman <andrew.banman@xxxxxxx> Cc: Andy Lutomirski <luto@xxxxxxxxxx> Cc: Anshuman Khandual <anshuman.khandual@xxxxxxx> Cc: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx> Cc: Baoquan He <bhe@xxxxxxxxxx> Cc: Benjamin Herrenschmidt <benh@xxxxxxxxxxxxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxxxx> Cc: Catalin Marinas <catalin.marinas@xxxxxxx> Cc: Chintan Pandya <cpandya@xxxxxxxxxxxxxx> Cc: Christophe Leroy <christophe.leroy@xxxxxx> Cc: Chris Wilson <chris@xxxxxxxxxxxxxxxxxx> 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: Jonathan Cameron <Jonathan.Cameron@xxxxxxxxxx> Cc: Joonsoo Kim <iamjoonsoo.kim@xxxxxxx> Cc: Jun Yao <yaojun8558363@xxxxxxxxx> Cc: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx> Cc: Logan Gunthorpe <logang@xxxxxxxxxxxx> Cc: Mark Brown <broonie@xxxxxxxxxx> Cc: Mark Rutland <mark.rutland@xxxxxxx> Cc: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> Cc: Michael Ellerman <mpe@xxxxxxxxxxxxxx> Cc: Mike Rapoport <rppt@xxxxxxxxxxxxxxxxxx> Cc: "mike.travis@xxxxxxx" <mike.travis@xxxxxxx> Cc: Nicholas Piggin <npiggin@xxxxxxxxx> Cc: Paul Mackerras <paulus@xxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: "Rafael J. Wysocki" <rafael@xxxxxxxxxx> Cc: Rich Felker <dalias@xxxxxxxx> Cc: Rob Herring <robh@xxxxxxxxxx> Cc: Robin Murphy <robin.murphy@xxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Tony Luck <tony.luck@xxxxxxxxx> Cc: Vasily Gorbik <gor@xxxxxxxxxxxxx> Cc: Will Deacon <will.deacon@xxxxxxx> Cc: Yoshinori Sato <ysato@xxxxxxxxxxxxxxxxxxxx> Cc: Yu Zhao <yuzhao@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- mm/memory_hotplug.c | 11 +++-------- 1 file changed, 3 insertions(+), 8 deletions(-) --- a/mm/memory_hotplug.c~mm-memory_hotplug-simplify-and-fix-check_hotplug_memory_range +++ a/mm/memory_hotplug.c @@ -1049,16 +1049,11 @@ int try_online_node(int nid) static int check_hotplug_memory_range(u64 start, u64 size) { - unsigned long block_sz = memory_block_size_bytes(); - u64 block_nr_pages = block_sz >> PAGE_SHIFT; - u64 nr_pages = size >> PAGE_SHIFT; - u64 start_pfn = PFN_DOWN(start); - /* memory range must be block size aligned */ - if (!nr_pages || !IS_ALIGNED(start_pfn, block_nr_pages) || - !IS_ALIGNED(nr_pages, block_nr_pages)) { + if (!size || !IS_ALIGNED(start, memory_block_size_bytes()) || + !IS_ALIGNED(size, memory_block_size_bytes())) { pr_err("Block size [%#lx] unaligned hotplug range: start %#llx, size %#llx", - block_sz, start, size); + memory_block_size_bytes(), start, size); return -EINVAL; } _
