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

David Hildenbrand david at redhat.com
Mon Oct 4 02:36:00 PDT 2021


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 <akpm at linux-foundation.org>
Cc: Mike Rapoport <rppt at kernel.org>
Cc: Michal Hocko <mhocko at suse.com>
Cc: Oscar Salvador <osalvador at suse.de>
Cc: Jianyong Wu <Jianyong.Wu at arm.com>
Cc: Aneesh Kumar K.V <aneesh.kumar at linux.ibm.com>
Cc: Vineet Gupta <vgupta at kernel.org>
Cc: Geert Uytterhoeven <geert at linux-m68k.org>
Cc: Huacai Chen <chenhuacai at kernel.org>
Cc: Jiaxun Yang <jiaxun.yang at flygoat.com>
Cc: Thomas Bogendoerfer <tsbogend at alpha.franken.de>
Cc: Heiko Carstens <hca at linux.ibm.com>
Cc: Vasily Gorbik <gor at linux.ibm.com>
Cc: Christian Borntraeger <borntraeger at de.ibm.com>
Cc: Eric Biederman <ebiederm at xmission.com>
Cc: Arnd Bergmann <arnd at arndb.de>
Cc: linux-snps-arc at lists.infradead.org
Cc: linux-ia64 at vger.kernel.org
Cc: linux-m68k at lists.linux-m68k.org
Cc: linux-mips at vger.kernel.org
Cc: linux-s390 at vger.kernel.org
Cc: linux-mm at kvack.org
Cc: kexec at lists.infradead.org

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
-- 
2.31.1




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