[PATCH v6 0/2] Fix acpi alignment fault with 'mem='

[Dennis Chen <dennis.chen-5wv7dgnIgG8@public.gmane.org>]

An ACPI alignment access fault has been observed on ARM platforms if one 
boots an ACPI enabled kernel with 'mem=' specificed. This was due to
memblock_enforce_memory_limit(.) throwing away NOMAP regions thus causing
acpi_os_ioremap(.) to map them as device memory (rather than normal memory).

This patch series fixes this issue by: 
 1) Introducing memblock_mem_limit_remove_map(.), which retains the NOMAP
    regions.
 2) Calling this function in arm64.

ChangeLog:
v5->v6: 
	- Truncate the reserved regions above the limit as suggested by
	  Steve Capper.
        - Drop the memblock debug fs related patch from this series since
	  it's independent logically. 
	- CC more relevant persons.
v4->v5:
        Fix a build warning.
v3->v4:
        Address some review comments from Mark Rutland.
v2->v3:
        Only keep the NOMAP regions above the limit while removing all other
        memblocks as suggested by Ard Biesheuvel.
v1->v2:
        Flag all regions above the limit as NOMAP as suggested by Mark Rutland.

Dennis Chen (2):
  mm:memblock Add new infrastructure to address the mem limit issue
  arm64:acpi Fix the acpi alignment exeception when 'mem=' specified

 arch/arm64/mm/init.c     |  2 +-
 include/linux/memblock.h |  1 +
 mm/memblock.c            | 57 +++++++++++++++++++++++++++++++++++++++++++-----
 3 files changed, 54 insertions(+), 6 deletions(-)

-- 
2.7.4