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charset="us-ascii" X-Rspamd-Server: rspam12 X-Rspamd-Queue-Id: 9E8961C000C X-Rspam-User: X-Stat-Signature: otccjtrnmx8nfm8ps9uayqffq98hac9p X-HE-Tag: 1746202921-783744 X-HE-Meta: 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 zZYk/vU9 JmVWL4EIk3pMnsZx4epQ7oTxcsvMn0riq8bEWRgethxKh+bUZB3LCIAh+ItrY8jusDBBgw2tRNiQMDx9FEUXJRIJzEmngNQ7mhkoIX798tAf1EJcEGPP6RAMHYAox90dAHVzMI0zMPZ5iCLBc8ZkwUy7U+Vh7f5C+x4kXVbE6QSAff2qEBjnzYRaT3CmA3Ox8CsD2j6fVngGMV0/foMdS9Vxc2ruBYVDqmzIXgJWBlE/osF4ongYVmtC4tXlAVp5KRyoZZTnL/8lEI3LRaeN1AIKKjNTq0Lr+YGXz2kgTfV6cFs6D2uRqpcnny71DGvI4alrPpGr5omvGbMRVi9IaNX70Pq9EcqVPDjFgfSCSSGNNJU4NTrh1vMsPLA0+6UkIN26oLozD35Q5AB4eGa035sXTGZYe7IdEWPwgZg/BoSoDJ805Y/ZBnoXDoLusXEkAdXeV0329TgXwsCGDGT1G5WkP0suBIMSXAjwnDbFULN8lVkRNIaltcIdyEP+vaMfg/CJqbRqy4Xh3pN+k3NXk/3E34pwkkHaNSpBPrlKASNYSTjDR6iN4M4l8M1Xxri0dLmQ8bOKi0bfcFsCE0cEd1e3eTwkXO0TRlM7i6FyNln2jpxnrEpnkNBfxy0gKA/VXRsnfQUJrEdME9mbyEp3+ceyQ8UcXOy+SVbwID0IKZE0/VWeA1Tm3ez6aoA+BjMIPAWvQui6gP3tzMhk= 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: List-Subscribe: List-Unsubscribe: On Fri, May 02, 2025, David Hildenbrand wrote: > On 30.04.25 20:58, Ackerley Tng wrote: > > > - if (is_private) > > > + if (is_gmem) > > > return max_level; > > > > I think this renaming isn't quite accurate. > > After our discussion yesterday, does that still hold true? No. > > IIUC in __kvm_mmu_max_mapping_level(), we skip considering > > host_pfn_mapping_level() if the gfn is private because private memory > > will not be mapped to userspace, so there's no need to query userspace > > page tables in host_pfn_mapping_level(). > > I think the reason was that: for private we won't be walking the user space > pages tables. > > Once guest_memfd is also responsible for the shared part, why should this > here still be private-only, and why should we consider querying a user space > mapping that might not even exist? +1, one of the big selling points for guest_memfd beyond CoCo is that it provides guest-first memory. It is very explicitly an intended feature that the guest mappings KVM creates can be a superset of the host userspace mappings. E.g. the guest can use larger page sizes, have RW while the host has RO, etc.