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charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Rspam-User: X-Rspamd-Queue-Id: 89F36C0017 X-Rspamd-Server: rspam09 X-Stat-Signature: 161p9y445rhtszf1bw1bemj1qdgguujn X-HE-Tag: 1682022091-90892 X-HE-Meta: U2FsdGVkX18wtf1kbVRV+Hd2fTJwyscEWDX7FV4kNIIJo7QFTJvg7XHPUp/uGeTrBxQBZDETVOBfyngL6ocJ90ZHCLxMBZOzbnDOJyCzSvIYzM/NwuxRBFaZThakbgB6uLou8DC/lpZ4KvCrUOdljU2O7LstV/D5muhnDlLFTwI6kHMrVic6kVUXs5Q8omZqOOczoiHIE6eQFZZfUF/9R1hvUGzJed2l3s9pW0NKmYqkzT1Tq3H7IkfNPKWkNeoGwKYRnPwU2MPDG8rFaDzvzrKsxZfwFHttvRidetaYTRu88zp3wOLF64AXyUcUzIRJ8XQaH1Ye7ALjH+2mLTiFNU1ogfdvpZhIpF+aqN6nI1Wgr2NGiOUeF/S60eor8VqVM7PZ7rp/LZRwYBGfc5+ubHeLXaOkAWNNZSuycsoj6QZexVsqim8vU6oDj8MMZ8ox1ySU5g4Zh9/PP21re4ZVsvd5arULofoz6sJBXt+pMpv2QR55u4DXj7j3xNsmxHWdaZKEM8SoVz3J3QIYYofYtLaWiwQBEVxw23lK0KKjVxqca9wtQ8e+sXqHZ+i0mYnGUIDNEnsPzv4dXWsCk8MtgFy+872vWvO3Jc26jSnTwakBiTvQ7xkOXedFvb4u+u7ovpEm7LqO5WIu9Ek5HJnkQq2XUthLnvvyhLm+E15GI9sS2lmcfdmzuUue2hjEAJuIPvEhfJRVw3Ra+MOKTqIsxQoJi8dVUBiCCArYwaXs4kcEzbsivfJMp7sQd0o0hmXXbepkTl7C05EB5q5Sie0oxoaWdqiucZ3oKKENwjdQX1lFSG3vu/OkP78H0FDHUmEl/+AGCTUli9V+HYYHtNyOGUJmR24vGrXfg3hgEWZIp0ZkJ2pw92BXmyIgkCcGlWNSalCnTrmPpppG4EquPnnz/RSh++Xgignh2yExn90dOS/rv1kU2rPodlcPjzolQvhPH5peRlCj+PB+cqNeZS+ gG0JSfEZ 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 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: On Fri, Apr 21, 2023, Atish Kumar Patra wrote: > On Thu, Apr 20, 2023 at 10:00=E2=80=AFPM Sean Christopherson wrote: > > > > On Wed, Apr 19, 2023, Atish Patra wrote: > > > 2. Lazy gstage page allocation vs upfront allocation with page pool. > > > Currently, all gstage mappings happen at runtime during the fault. Th= is is expensive > > > as we need to convert that page to confidential memory as well. A pag= e pool framework > > > may be a better choice which can hold all the confidential pages whic= h can be > > > pre-allocated upfront. A generic page pool infrastructure may benefit= other CC solutions ? > > > > I'm sorry, what? Do y'all really not pay any attention to what is happ= ening > > outside of the RISC-V world? > > > > We, where "we" is KVM x86 and ARM, with folks contributing from 5+ comp= anines, > > have been working on this problem for going on three *years*. And that= 's just > > from the first public posting[1], there have been discussions about how= to approach > > this for even longer. There have been multiple related presentations a= t KVM Forum, > > something like 4 or 5 just at KVM Forum 2022 alone. > > >=20 > I did mention about that in the 1st item in the TODO list. My apologies, I completely missed the todo list. > Thanks for your suggestion. It seems we should just directly move to > restrictedmem asap. Yes please, for the sake of everyone involved. It will likely save you fro= m running into the same pitfalls that x86 and ARM already encountered, and th= e more eyeballs and use cases on whatever restrictemem ends up being called, the b= etter. Thanks!