The scratch memory for kexec handover is used to bootstrap the
kexec'ed kernel. Only the 1st 1MB is used as scratch, and its a
hack to get around limitations with KHO. It is only needed when
CONFIG_KEXEC_HANDOVER is enabled and only if it is a KHO boot
(both checked by is_kho_boot). Add check to prevent marking a KHO
scratch region unless needed.

CONFIG_MEMBLOCK_KHO_SCRATCH is also removed as its only selected
by KEXEC_HANDOVER.

v2 -> v3:
- is_kho_boot already has stubs when CONFIG_KEXEC_HANDOVER=n,
  no need to move the functions under CONFIG_KEXEC_HANDOVER (Pratyush
  Yadav)
- Commit messsage improvements

v1 -> v2:
- Remove CONFIG_MEMBLOCK_KHO_SCRATCH (Kiryl Shutsemau)
- Move memblock_mark/clear_kho_scratch under alread existing
  CONFIG_KEXEC_HANDOVER in memblock.c.


Usama Arif (2):
  mm/memblock: remove CONFIG_MEMBLOCK_KHO_SCRATCH option
  mm/memblock: only mark/clear KHO scratch memory when needed

 include/linux/memblock.h |  2 +-
 kernel/Kconfig.kexec     |  1 -
 mm/Kconfig               |  4 ----
 mm/memblock.c            | 18 +++++++++++-------
 4 files changed, 12 insertions(+), 13 deletions(-)

-- 
2.47.3