linux/arch/x86/mm
Pavel Tatashin 078eb6aa50 x86/mm/memory_hotplug: determine block size based on the end of boot memory
Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86, the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hot-plugging/hot-removing can be broken.

Memory sections are combined into "memory block" chunks.  These chunks
are the units upon which memory can be added and removed.

On x86 the new memory may be added after the end of the boot memory,
therefore, if block size does not align with end of boot memory, memory
hotplugging/hotremoving can be broken.

Currently, whenever machine is booted with more than 64G the block size
is unconditionally increased to 2G from the base 128M.  This is done in
order to reduce number of memory device files in sysfs:

	/sys/devices/system/memory/memoryXXX

We must use the largest allowed block size that aligns to the next
address to be able to hotplug the next block of memory.

So, when memory is larger or equal to 64G, we check the end address and
find the largest block size that is still power of two but smaller or
equal to 2G.

Before, the fix:
Run qemu with:
-m 64G,slots=2,maxmem=66G -object memory-backend-ram,id=mem1,size=2G

(qemu) device_add pc-dimm,id=dimm1,memdev=mem1
Block size [0x80000000] unaligned hotplug range: start 0x1040000000,
							size 0x80000000
acpi PNP0C80:00: add_memory failed
acpi PNP0C80:00: acpi_memory_enable_device() error
acpi PNP0C80:00: Enumeration failure

With the fix memory is added successfully as the block size is set to
1G, and therefore aligns with start address 0x1040000000.

[pasha.tatashin@oracle.com: v4]
  Link: http://lkml.kernel.org/r/20180215165920.8570-3-pasha.tatashin@oracle.com
Link: http://lkml.kernel.org/r/20180213193159.14606-3-pasha.tatashin@oracle.com
Signed-off-by: Pavel Tatashin <pasha.tatashin@oracle.com>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Steven Sistare <steven.sistare@oracle.com>
Cc: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Bharata B Rao <bharata@linux.vnet.ibm.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Cc: Baoquan He <bhe@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2018-04-05 21:36:25 -07:00
..
Makefile x86/mm/sme: Disable stack protection for mem_encrypt_identity.c 2018-02-28 15:24:12 +01:00
amdtopology.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
cpu_entry_area.c x86/cpu_entry_area: Sync cpu_entry_area to initial_page_table 2018-03-01 09:48:27 +01:00
debug_pagetables.c x86/efi: Replace efi_pgd with efi_mm.pgd 2018-03-12 11:05:05 +01:00
dump_pagetables.c x86/mm: Consider effective protection attributes in W+X check 2018-02-26 08:43:21 +01:00
extable.c x86/extable: Mark exception handler functions visible 2018-01-14 20:04:16 +01:00
fault.c Merge branch 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-04-02 15:45:30 -07:00
highmem_32.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
hugetlbpage.c x86/mm: Prevent non-MAP_FIXED mapping across DEFAULT_MAP_WINDOW border 2017-11-16 11:43:11 +01:00
ident_map.c x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks 2018-02-16 10:48:49 +01:00
init.c Merge branch 'x86-pti-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-01-05 12:23:57 -08:00
init_32.c x86/cpu_entry_area: Sync cpu_entry_area to initial_page_table 2018-03-01 09:48:27 +01:00
init_64.c x86/mm/memory_hotplug: determine block size based on the end of boot memory 2018-04-05 21:36:25 -07:00
iomap_32.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
ioremap.c x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]() 2018-02-15 01:15:52 +01:00
kasan_init_64.c x86/mm: Optimize boot-time paging mode switching cost 2018-02-21 10:19:18 +01:00
kaslr.c x86/mm: Replace compile-time checks for 5-level paging with runtime-time checks 2018-02-16 10:48:49 +01:00
kmmio.c x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]() 2018-02-15 01:15:52 +01:00
mem_encrypt.c dma/direct: Handle force decryption for DMA coherent buffers in common code 2018-03-20 10:01:59 +01:00
mem_encrypt_boot.S x86/mm/sme, objtool: Annotate indirect call in sme_encrypt_execute() 2018-02-21 09:05:04 +01:00
mem_encrypt_identity.c x86/mm/sme: Disable stack protection for mem_encrypt_identity.c 2018-02-28 15:24:12 +01:00
mm_internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
mmap.c x86/mm: Limit mmap() of /dev/mem to valid physical addresses 2017-11-16 12:49:48 +01:00
mmio-mod.c x86: do not use print_symbol() 2018-01-05 15:23:01 +01:00
mpx.c Merge branch 'x86/mpx' into x86/asm, to pick up dependent commits 2017-11-08 10:55:48 +01:00
numa.c Merge branch 'x86/boot' into x86/mm, to avoid conflict 2017-04-11 08:56:05 +02:00
numa_32.c x86/mm/32: Remove unused node_memmap_size_bytes() & CONFIG_NEED_NODE_MEMMAP_SIZE logic 2018-03-27 08:45:02 +02:00
numa_64.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
numa_emulation.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
numa_internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pageattr-test.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pageattr.c kmemcheck: stop using GFP_NOTRACK and SLAB_NOTRACK 2017-11-15 18:21:04 -08:00
pat.c x86/mm: add a function to check if a pfn is UC/UC-/WC 2018-01-16 16:40:09 +01:00
pat_internal.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pat_rbtree.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pf_in.c x86/mm: Audit and remove any unnecessary uses of module.h 2016-07-14 13:04:20 +02:00
pf_in.h
pgtable.c x86/mm: implement free pmd/pte page interfaces 2018-03-22 17:07:01 -07:00
pgtable_32.c x86/mm: Rename flush_tlb_single() and flush_tlb_one() to __flush_tlb_one_[user|kernel]() 2018-02-15 01:15:52 +01:00
physaddr.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
physaddr.h License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
pkeys.c x86/fpu: Rename fpu::fpstate_active to fpu::initialized 2017-09-26 09:43:36 +02:00
pti.c x86/pti: Fix a comment typo 2018-03-08 12:33:21 +01:00
setup_nx.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
srat.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
testmmiotrace.c Annotate hardware config module parameters in arch/x86/mm/ 2017-04-04 16:54:21 +01:00
tlb.c Merge branch 'x86/mm' into efi/core 2018-03-12 10:03:09 +01:00