On Tue, Jun 18, 2019 at 10:51:33PM -0700, Dan Williams wrote: > Changes since v9 [1]: > - Fix multiple issues related to the fact that pfn_valid() has > traditionally returned true for any pfn in an 'early' (onlined at > boot) section regardless of whether that pfn represented 'System RAM'. > Teach pfn_valid() to maintain its traditional behavior in the presence > of subsections. Specifically, subsection precision for pfn_valid() is > only considered for non-early / hot-plugged sections. (Qian) > > - Related to the first item introduce a SECTION_IS_EARLY > (->section_mem_map flag) to remove the existing hacks for determining > an early section by looking at whether the usemap was allocated from the > slab. > > - Kill off the EEXIST hackery in __add_pages(). It breaks > (arch_add_memory() false-positive) the detection of subsection > collisions reported by section_activate(). It is also obviated by > David's recent reworks to move the 'System RAM' request_region() earlier > in the add_memory() sequence(). > > - Switch to an arch-independent / static subsection-size of 2MB. > Otherwise, a per-arch subsection-size is a roadblock on the path to > persistent memory namespace compatibility across archs. (Jeff) > > - Update the changelog for "libnvdimm/pfn: Fix fsdax-mode namespace > info-block zero-fields" to clarify that the "Cc: stable" is only there > as safety measure for a distro that decides to backport "libnvdimm/pfn: > Stop padding pmem namespaces to section alignment", otherwise there is > no known bug exposure in older kernels. (Andrew) > > - Drop some redundant subsection checks (Oscar) > > - Collect some reviewed-bys > > [1]: https://lore.kernel.org/lkml/155977186863.2443951.9036044808311959913.stgit@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx/ Hi Dan, I am planning to give it a final review later tomorrow. Now that this work is settled, I took the chance to dust off and push my vmemmap-hotplug, and I am working on that right now. But I would definetely come back to this tomorrow. Thanks for the work -- Oscar Salvador SUSE L3
