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Peter Anvin" , "Paul E. McKenney" , Andrey Konovalov , Andrey Ryabinin , Andy Lutomirski , Borislav Petkov , Catalin Marinas , Christoph Lameter , Dave Hansen , David Rientjes , Dmitriy Vyukov , Eric Dumazet , Greg Kroah-Hartman , Hillf Danton , Ingo Molnar , Jann Horn , Jonathan.Cameron@huawei.com, Jonathan Corbet , Joonsoo Kim , Kees Cook , Mark Rutland , Pekka Enberg , Peter Zijlstra , sjpark@amazon.com, Thomas Gleixner , Vlastimil Babka , "the arch/x86 maintainers" , "open list:DOCUMENTATION" , LKML , kasan-dev , Linux ARM , Linux Memory Management List Content-Type: text/plain; charset="UTF-8" X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: Will, > Given that the pool is relatively small (i.e. when compared with our virtual > address space), dedicating an area of virtual space sounds like it makes > the most sense here. How early do you need it to be available? How do we assign struct pages to a fixed virtual space area (I'm currently experimenting with 0xffff7f0000000000-0xffff7f0000200000)? Looks like filling page table entries (similarly to what's being done in arch/arm64/mm/kasan_init.c) is not enough. I thought maybe vmemmap_populate() would do the job, but it didn't (virt_to_pfn() still returns invalid PFNs).