[PATCH v2 0/2] fix devm_memremap_pages() mem hotplug locking

[Dan Williams <dan.j.williams@intel.com>]

Changes since v1 [1]:
* Reflowed the patches on 4.10-rc8. The v1 series no longer applies
  to -mm now that the sub-section memory hotplug support has been
  deferred to 4.12 [2].

[1]: https://lists.01.org/pipermail/linux-nvdimm/2017-February/008848.html
[2]: http://www.spinics.net/lists/linux-mm/msg121990.html

---

Ben notes that commit f931ab479dd2 "mm: fix devm_memremap_pages crash,
use mem_hotplug_{begin, done}" is incomplete and broken. Writes to
mem_hotplug.active_writer need to be coordinated under the device
hotplug lock. Otherwise, we can potentially corrupt mem_hotplug.refcount
leading to soft lockups.

---

Dan Williams (2):
      mm, devm_memremap_pages: hold device_hotplug lock over mem_hotplug_{begin,done}
      mm: validate device_hotplug is held for memory hotplug


 drivers/base/core.c    |    5 +++++
 include/linux/device.h |    1 +
 kernel/memremap.c      |    6 ++++++
 mm/memory_hotplug.c    |    2 ++
 4 files changed, 14 insertions(+)

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