On Mon, Aug 17, 2015 at 2:45 PM, Jerome Glisse <j.gli...@gmail.com> wrote: > On Fri, Aug 14, 2015 at 07:11:27PM -0700, Dan Williams wrote: >> Although it does not offer perfect protection if device memory is at a >> physically lower address than RAM, skipping the update of these >> variables does seem to be what we want. For example /dev/mem would >> fail to allow write access to persistent memory if it fails a >> valid_phys_addr_range() check. Since /dev/mem does not know how to >> write to PMEM in a reliably persistent way, it should not treat a >> PMEM-pfn like RAM. > > So i attach is a patch that should keep ZONE_DEVICE out of consideration > for the buddy allocator. You might also want to keep page reserved and not > free inside the zone, you could replace the generic_online_page() using > set_online_page_callback() while hotpluging device memory. >
Hmm, are we already protected by the fact that ZONE_DEVICE is not represented in the GFP_ZONEMASK? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
