Kernel can crash on failed VM_BUG_ON assertion in function move_freepages()
on some rare physical memory mappings (with huge range(s) of memory
reserved by BIOS followed by usable memory not aligned to pageblock).

crash> page_init_bug -v | grep resource | sed '/RAM .3/,/RAM .4/!d'
<struct resource 0xffff88067fffd480>      4bfac000 -     646b1fff       System 
RAM (391.02 MiB = 400408.00 KiB)
<struct resource 0xffff88067fffd4b8>      646b2000 -     793fefff       
reserved (333.30 MiB = 341300.00 KiB)
<struct resource 0xffff88067fffd4f0>      793ff000 -     7b3fefff       ACPI 
Non-volatile Storage ( 32.00 MiB)
<struct resource 0xffff88067fffd528>      7b3ff000 -     7b787fff       ACPI 
Tables (  3.54 MiB = 3620.00 KiB)
<struct resource 0xffff88067fffd560>      7b788000 -     7b7fffff       System 
RAM (480.00 KiB)

More details in second patch.

v2: Use -1 constant for max_pfn and remove the parameter. That's
    mostly just a cosmetics.
v3: Split to two patches series to make clear what is the actual fix
    and what is just a clean up. No code changes compared to v2 and
    second patch is identical to original v1.


Daniel Vacek (2):
  mm/memblock: hardcode the max_pfn being -1
  mm/page_alloc: fix memmap_init_zone pageblock alignment

 mm/memblock.c   | 13 ++++++-------
 mm/page_alloc.c |  9 +++++++--
 2 files changed, 13 insertions(+), 9 deletions(-)


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