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Shutemov" Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Stat-Signature: o73afgm1hmp4mf7sc9jtmkrugaxghein X-Rspamd-Server: rspam07 X-Rspamd-Queue-Id: EA761C0006 X-HE-Tag: 1699053445-974218 X-HE-Meta: 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 m0mxxcNg 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 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000007, 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 Thu, Nov 02, 2023, Fuad Tabba wrote: > On Wed, Nov 1, 2023 at 9:55=E2=80=AFPM Sean Christopherson wrote: > > E.g. a misbehaving userspace could prematurely delete a memslot. And t= he more > > fun example is intrahost migration, where the plan is to allow pointing= multiple > > guest_memfd files at a single guest_memfd inode: > > https://lore.kernel.org/all/cover.1691446946.git.ackerleytng@google.com > > > > There was a lot of discussion for this, but it's scattered all over the= place. > > The TL;DR is is that the inode will represent physical memory, and a fi= le will > > represent a given "struct kvm" instance's view of that memory. And so = the memory > > isn't reclaimed until the inode is truncated/punched. > > > > I _think_ this reflects the most recent plan from the guest_memfd side: > > https://lore.kernel.org/all/1233d749211c08d51f9ca5d427938d47f008af1f.16= 89893403.git.isaku.yamahata@intel.com Doh, sitting in my TODO folder... https://lore.kernel.org/all/20231016115028.996656-1-michael.roth@amd.com > Thanks for pointing that out. I think this might be the way to go. > I'll have a closer look at this and see how to get it to work with > pKVM.