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Tue, 31 Oct 2023 15:18:17 -0700 (PDT) X-Google-Smtp-Source: AGHT+IGQrBiQJHLqXrbYP+Ue59NphHDME9ef8CfXr1engDM3UMhS/wxqjXJBm4DCAAdJKCtZSXIUO7Qf2zwxIf8biNY= X-Received: by 2002:a67:c218:0:b0:44e:99a2:a42 with SMTP id i24-20020a67c218000000b0044e99a20a42mr9981736vsj.11.1698790696825; Tue, 31 Oct 2023 15:18:16 -0700 (PDT) MIME-Version: 1.0 References: <20231027182217.3615211-1-seanjc@google.com> <20231027182217.3615211-17-seanjc@google.com> In-Reply-To: From: Paolo Bonzini Date: Tue, 31 Oct 2023 23:18:04 +0100 Message-ID: Subject: Re: [PATCH v13 16/35] KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory To: Sean Christopherson Cc: Fuad Tabba , Marc Zyngier , Oliver Upton , Huacai Chen , Michael Ellerman , Anup Patel , Paul Walmsley , Palmer Dabbelt , Albert Ou , Alexander Viro , Christian Brauner , "Matthew Wilcox (Oracle)" , Andrew Morton , kvm@vger.kernel.org, linux-arm-kernel@lists.infradead.org, kvmarm@lists.linux.dev, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, kvm-riscv@lists.infradead.org, linux-riscv@lists.infradead.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, Xiaoyao Li , Xu Yilun , Chao Peng , Jarkko Sakkinen , Anish Moorthy , David Matlack , Yu Zhang , Isaku Yamahata , =?UTF-8?B?TWlja2HDq2wgU2FsYcO8bg==?= , Vlastimil Babka , Vishal Annapurve , Ackerley Tng , Maciej Szmigiero , David Hildenbrand , Quentin Perret , Michael Roth , Wang , Liam Merwick , Isaku Yamahata , "Kirill A . Shutemov" X-Mimecast-Spam-Score: 0 X-Mimecast-Originator: redhat.com Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Rspamd-Queue-Id: 87862180023 X-Rspam-User: X-Rspamd-Server: rspam02 X-Stat-Signature: 4oke1nxdumhzz3jjao5yxpwhtqtomepq X-HE-Tag: 1698790709-194756 X-HE-Meta: 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 Yki0QTnv Bk5C6qnqmjF+kNFzsiUs8CYIjS/bjNcJli9wu+MU/p8u/z+c469HTGs/1wOGsi9OS7KnVY0Wy3rU0/8GyCKcYffPRDCbDac04TTN/FGSWwlQMEGX7pzilXw6Gw8tQbygsWiljuEnxqYkYb1YXPZNrE4JubJ3yhhvIyJAXIFkY3tFNXdvRIIhdgrGgu/amBgOp1RjHfv/xwaC2pHQMOknw1fE1xI7CVX5UnDdt2ok+6YIrHBmRgpcfwZG0FciaSZnkcEna+i9BBGaayzvCLELSnqhnOv6VNAceC+pdLXyICvLkitsRvzkr5eRp6ZiLbtsy94sWu4HNu1l7V6rhl150A6WgqpboCFeMaepNQeDgdHRQhHYWG1UPkPcknGaqTHAQUlKxO67j5kuz+CDM2+aPehDR8lGARkTKLe2d 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 Tue, Oct 31, 2023 at 11:13=E2=80=AFPM Sean Christopherson wrote: > On Tue, Oct 31, 2023, Fuad Tabba wrote: > > On Fri, Oct 27, 2023 at 7:23=E2=80=AFPM Sean Christopherson wrote: > Since we now know that at least pKVM will use guest_memfd for shared memo= ry, and > odds are quite good that "regular" VMs will also do the same, i.e. will w= ant > guest_memfd with the concept of private memory, I agree that we should av= oid > PRIVATE. > > Though I vote for KVM_MEM_GUEST_MEMFD (or KVM_MEM_GUEST_MEMFD_VALID or > KVM_MEM_USE_GUEST_MEMFD). I.e. do our best to avoid ambiguity between re= ferring > to "guest memory" at-large and guest_memfd. I was going to propose KVM_MEM_HAS_GUESTMEMFD. Any option is okay for me so, if no one complains, I'll go for KVM_MEM_GUESTMEMFD (no underscore because I found the repeated "_MEM" distracting). Paolo