Messages in this thread | | | From | Dan Williams <> | Date | Wed, 17 Apr 2019 15:59:46 -0700 | Subject | Re: [PATCH v6 00/12] mm: Sub-section memory hotplug support |
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On Wed, Apr 17, 2019 at 3:04 PM Andrew Morton <akpm@linux-foundation.org> wrote: > > On Wed, 17 Apr 2019 11:38:55 -0700 Dan Williams <dan.j.williams@intel.com> wrote: > > > The memory hotplug section is an arbitrary / convenient unit for memory > > hotplug. 'Section-size' units have bled into the user interface > > ('memblock' sysfs) and can not be changed without breaking existing > > userspace. The section-size constraint, while mostly benign for typical > > memory hotplug, has and continues to wreak havoc with 'device-memory' > > use cases, persistent memory (pmem) in particular. Recall that pmem uses > > devm_memremap_pages(), and subsequently arch_add_memory(), to allocate a > > 'struct page' memmap for pmem. However, it does not use the 'bottom > > half' of memory hotplug, i.e. never marks pmem pages online and never > > exposes the userspace memblock interface for pmem. This leaves an > > opening to redress the section-size constraint. > > v6 and we're not showing any review activity. Who would be suitable > people to help out here?
There was quite a bit of review of the cover letter from Michal and David, but you're right the details not so much as of yet. I'd like to call out other people where I can reciprocate with some review of my own. Oscar's altmap work looks like a good candidate for that.
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