On Tue, Apr 11, 2017 at 10:42 AM, Oliver O'Halloran <ooh...@gmail.com> wrote: > Hi all, > > This series adds support for ZONE_DEVICE and the pmem api on powerpc. Namely, > support for altmaps and the various bits and pieces required for DAX PMD > faults. > The first two patches touch generic mm/ code, but otherwise this is fairly > well > contained in arch/powerpc. > > If the nvdimm folks could sanity check this series I'd appreciate it.
Quick feedback: I'm in the process of cleaning up and resubmitting my patch set to push the pmem api down into the driver directly. https://lwn.net/Articles/713064/ I'm also reworking memory hotplug to allow sub-section allocations which has collided with Michal Hocko's hotplug reworks. It will be good to have some more eyes on that work to understand the cross-arch implications. https://lkml.org/lkml/2017/3/19/146 > Series is based on next-20170411, but it should apply elsewhere with minor > fixups to arch_{add|remove}_memory due to conflicts with HMM. For those > interested in testing this, there is a driver and matching firmware that > carves > out some system memory for use as an emulated Con Tutto memory card. > > Driver: https://github.com/oohal/linux/tree/contutto-next > Firmware: https://github.com/oohal/skiboot/tree/fake-contutto > > Edit core/init.c:686 to control the amount of memory borrowed for the emulated > device. I'm keeping the driver out of tree for a until 4.13 since I plan on > reworking the firmware interface anyway and There's at least one showstopper > bug. Is this memory card I/O-cache coherent? I.e. existing dma mapping api can hand out mappings to it? Just trying to figure out if this the existing pmem-definition of ZONE_DEVICE or a new one.