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Sampat" , Ackerley Tng , Fuad Tabba , Xu Yilun , "Aneesh Kumar K . V" Content-Type: text/plain; charset="us-ascii" On Wed, Feb 25, 2026, Alexey Kardashevskiy wrote: > For the new guest_memfd type, no additional reference is taken as > pinning is guaranteed by the KVM guest_memfd library. > > There is no KVM-GMEMFD->IOMMUFD direct notification mechanism as > the assumption is that: > 1) page stage change events will be handled by VMM which is going > to call IOMMUFD to remap pages; > 2) shrinking GMEMFD equals to VM memory unplug and VMM is going to > handle it. The VMM is outside of the kernel's effective TCB. Assuming the VMM will always do the right thing is a non-starter.