[v2,0/5] mm/memory_hotplug: full support for add_memory_driver_managed() with CONFIG_ARCH_KEEP_MEMBLOCK

Message

David Hildenbrand Oct. 4, 2021, 9:36 a.m. UTC

Architectures that require CONFIG_ARCH_KEEP_MEMBLOCK=y, such as arm64,
don't cleanly support add_memory_driver_managed() yet. Most prominently,
kexec_file can still end up placing kexec images on such driver-managed
memory, resulting in undesired behavior, for example, having kexec images
located on memory not part of the firmware-provided memory map.

Teaching kexec to not place images on driver-managed memory is especially
relevant for virtio-mem. Details can be found in commit 7b7b27214bba
("mm/memory_hotplug: introduce add_memory_driver_managed()").

Extend memblock with a new flag and set it from memory hotplug code
when applicable. This is required to fully support virtio-mem on
arm64, making also kexec_file behave like on x86-64.

v1 -> v2:
- "memblock: improve MEMBLOCK_HOTPLUG documentation"
-- Added
- "memblock: add MEMBLOCK_DRIVER_MANAGED to mimic
   IORESOURCE_SYSRAM_DRIVER_MANAGED"
-- Improve documentation of MEMBLOCK_DRIVER_MANAGED
- Refine patch descriptions

Cc: Andrew Morton <[e-mail]>
Cc: Mike Rapoport <[e-mail]>
Cc: Michal Hocko <[e-mail]>
Cc: Oscar Salvador <[e-mail]>
Cc: Jianyong Wu <[e-mail]>
Cc: Aneesh Kumar K.V <[e-mail]>
Cc: Vineet Gupta <[e-mail]>
Cc: Geert Uytterhoeven <[e-mail]>
Cc: Huacai Chen <[e-mail]>
Cc: Jiaxun Yang <[e-mail]>
Cc: Thomas Bogendoerfer <[e-mail]>
Cc: Heiko Carstens <[e-mail]>
Cc: Vasily Gorbik <[e-mail]>
Cc: Christian Borntraeger <[e-mail]>
Cc: Eric Biederman <[e-mail]>
Cc: Arnd Bergmann <[e-mail]>
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]
Cc: [e-mail]

David Hildenbrand (5):
  mm/memory_hotplug: handle memblock_add_node() failures in
    add_memory_resource()
  memblock: improve MEMBLOCK_HOTPLUG documentation
  memblock: allow to specify flags with memblock_add_node()
  memblock: add MEMBLOCK_DRIVER_MANAGED to mimic
    IORESOURCE_SYSRAM_DRIVER_MANAGED
  mm/memory_hotplug: indicate MEMBLOCK_DRIVER_MANAGED with
    IORESOURCE_SYSRAM_DRIVER_MANAGED

 arch/arc/mm/init.c               |  4 ++--
 arch/ia64/mm/contig.c            |  2 +-
 arch/ia64/mm/init.c              |  2 +-
 arch/m68k/mm/mcfmmu.c            |  3 ++-
 arch/m68k/mm/motorola.c          |  6 ++++--
 arch/mips/loongson64/init.c      |  4 +++-
 arch/mips/sgi-ip27/ip27-memory.c |  3 ++-
 arch/s390/kernel/setup.c         |  3 ++-
 include/linux/memblock.h         | 25 +++++++++++++++++++++----
 include/linux/mm.h               |  2 +-
 kernel/kexec_file.c              |  5 +++++
 mm/memblock.c                    | 13 +++++++++----
 mm/memory_hotplug.c              | 11 +++++++++--
 13 files changed, 62 insertions(+), 21 deletions(-)


base-commit: 9e1ff307c779ce1f0f810c7ecce3d95bbae40896