>>> On 11.10.16 at 17:53, <dan.j.willi...@intel.com> wrote: > On Tue, Oct 11, 2016 at 6:08 AM, Jan Beulich <jbeul...@suse.com> wrote: >>>>> Andrew Cooper <andrew.coop...@citrix.com> 10/10/16 6:44 PM >>> >>>On 10/10/16 01:35, Haozhong Zhang wrote: >>>> Xen hypervisor needs assistance from Dom0 Linux kernel for following tasks: >>>> 1) Reserve an area on NVDIMM devices for Xen hypervisor to place >>>> memory management data structures, i.e. frame table and M2P table. >>>> 2) Report SPA ranges of NVDIMM devices and the reserved area to Xen >>>> hypervisor. >>> >>>However, I can't see any justification for 1). Dom0 should not be >>>involved in Xen's management of its own frame table and m2p. The mfns >>>making up the pmem/pblk regions should be treated just like any other >>>MMIO regions, and be handed wholesale to dom0 by default. >> >> That precludes the use as RAM extension, and I thought earlier rounds of >> discussion had got everyone in agreement that at least for the pmem case >> we will need some control data in Xen. > > The missing piece for me is why this reservation for control data > needs to be done in the libnvdimm core? I would expect that any dax > capable file could be mapped and made available to a guest. This > includes /dev/ramX devices that are dax capable, but are external to > the libnvdimm sub-system.
Despite me being the only one on the To list, I don't think the question was really meant to be directed to me. Jan _______________________________________________ Linux-nvdimm mailing list Linux-nvdimm@lists.01.org https://lists.01.org/mailman/listinfo/linux-nvdimm