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charset="us-ascii" On Tue, Oct 20, 2026, Paolo Bonzini wrote: > A late review of the guest_memfd attributes changes... > > With Linux 7.4 the "private" memory attribute was moved from the VM > to the individual guest_memfd file descriptor. The old semantics are > available for backwards compatibility via CONFIG_KVM_VM_MEMORY_ATTRIBUTES, > and disabled by default. > > This change has two problems: first, it ties support for VM memory > attributes entirely to a backwards compatibility symbol for distros. > Second, it is incompatible with all released versions of QEMU (and > perhaps most other VMMs?), thus the default is arguably not the > right one. I was hoping we could go with a stick approach, but given how painful double-allocating is, hopefully a carrot will work too. :-)