I would like to get this queued up to get merged. Since most of the churn is in the nvdimm code, and it also depends on some refactoring that only exists in the nvdimm tree, it seems like putting it in *via* the nvdimm tree is the best path. But, this series makes non-trivial changes to the "resource" code and memory hotplug. I'd really like to get some acks from folks on the first three patches which affect those areas. Borislav and Bjorn, you seem to be the most active in the resource code. Michal, I'd really appreciate at look at all of this from a mem hotplug perspective. Note: these are based on commit d2f33c19644 in: git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm.git libnvdimm-pending Changes since v1: * Now based on git://git.kernel.org/pub/scm/linux/kernel/git/djbw/nvdimm.git * Use binding/unbinding from "dax bus" code * Move over to a "dax bus" driver from being an nvdimm driver -- Persistent memory is cool. But, currently, you have to rewrite your applications to use it. Wouldn't it be cool if you could just have it show up in your system like normal RAM and get to it like a slow blob of memory? Well... have I got the patch series for you! This series adds a new "driver" to which pmem devices can be attached. Once attached, the memory "owned" by the device is hot-added to the kernel and managed like any other memory. On systems with an HMAT (a new ACPI table), each socket (roughly) will have a separate NUMA node for its persistent memory so this newly-added memory can be selected by its unique NUMA node. Here's how I set up a system to test this thing: 1. Boot qemu with lots of memory: "-m 4096", for instance 2. Reserve 512MB of physical memory. Reserving a spot a 2GB physical seems to work: memmap=512M!0x0000000080000000 This will end up looking like a pmem device at boot. 3. When booted, convert fsdax device to "device dax": ndctl create-namespace -fe namespace0.0 -m dax 4. See patch 4 for instructions on binding the kmem driver to a device. 5. Now, online the new memory sections. Perhaps: grep ^MemTotal /proc/meminfo for f in `grep -vl online /sys/devices/system/memory/*/state`; do echo $f: `cat $f` echo online_movable > $f grep ^MemTotal /proc/meminfo done Cc: Dan Williams <dan.j.williams@xxxxxxxxx> Cc: Dave Jiang <dave.jiang@xxxxxxxxx> Cc: Ross Zwisler <zwisler@xxxxxxxxxx> Cc: Vishal Verma <vishal.l.verma@xxxxxxxxx> Cc: Tom Lendacky <thomas.lendacky@xxxxxxx> Cc: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: linux-nvdimm@xxxxxxxxxxxx Cc: linux-kernel@xxxxxxxxxxxxxxx Cc: linux-mm@xxxxxxxxx Cc: Huang Ying <ying.huang@xxxxxxxxx> Cc: Fengguang Wu <fengguang.wu@xxxxxxxxx> Cc: Borislav Petkov <bp@xxxxxxx> Cc: Bjorn Helgaas <bhelgaas@xxxxxxxxxx> Cc: Yaowei Bai <baiyaowei@xxxxxxxxxxxxxxxxxxxx> Cc: Takashi Iwai <tiwai@xxxxxxx>
