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charset="utf-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 46EFD20016 X-Stat-Signature: ompcocscjseneqn3rp8kcr7e3j6ad8qh X-Rspam-User: X-Rspamd-Server: rspam10 X-HE-Tag: 1752190411-765531 X-HE-Meta: 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 z2QM4Rtv 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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: List-Subscribe: List-Unsubscribe: On Wed, Jul 09, 2025, Vishal Annapurve wrote: > On Wed, Jul 9, 2025 at 8:00=E2=80=AFAM Sean Christopherson wrote: > > > > On Wed, Jul 09, 2025, Vishal Annapurve wrote: > > > I think we can simplify the role of guest_memfd in line with discussi= on [1]: > > > > I genuinely don't understand what you're trying to "simplify". We need= to define > > an ABI that is flexible and robust, but beyond that most of these guide= lines boil > > down to "don't write bad code". >=20 > My goal for bringing this discussion up is to see if we can better > define the role of guest_memfd and how it interacts with other layers, > as I see some scenarios that can be improved like kvm_gmem_populate[1] > where guest_memfd is trying to fault in pages on behalf of KVM. Ah, gotcha. From my perspective, it's all just KVM, which is why I'm not f= eeling the same sense of urgency to formally define anything. We want to encapsul= ate code, have separate of concerns, etc., but I don't see that as being anythi= ng unique or special to guest_memfd. We try to achieve the same for all major= areas of KVM, though obviously with mixed results :-)