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Hallyn" Cc: 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-security-module@vger.kernel.org, linux-kernel@vger.kernel.org, Chao Peng , Fuad Tabba , Jarkko Sakkinen , Yu Zhang , Vishal Annapurve , Ackerley Tng , Maciej Szmigiero , Vlastimil Babka , David Hildenbrand , Quentin Perret , Michael Roth , Wang , Liam Merwick , Isaku Yamahata , "Kirill A . Shutemov" References: <20230718234512.1690985-1-seanjc@google.com> <20230718234512.1690985-13-seanjc@google.com> From: Xiaoyao Li In-Reply-To: <20230718234512.1690985-13-seanjc@google.com> X-CRM114-Version: 20100106-BlameMichelson ( TRE 0.8.0 (BSD) ) MR-646709E3 X-CRM114-CacheID: sfid-20230720_074628_093836_E4C65570 X-CRM114-Status: UNSURE ( 9.61 ) X-CRM114-Notice: Please train this message. X-BeenThere: linux-arm-kernel@lists.infradead.org X-Mailman-Version: 2.1.34 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Transfer-Encoding: 7bit Content-Type: text/plain; charset="us-ascii"; Format="flowed" Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=archiver.kernel.org@lists.infradead.org On 7/19/2023 7:44 AM, Sean Christopherson wrote: > @@ -5134,6 +5167,16 @@ static long kvm_vm_ioctl(struct file *filp, > case KVM_GET_STATS_FD: > r = kvm_vm_ioctl_get_stats_fd(kvm); > break; > + case KVM_CREATE_GUEST_MEMFD: { > + struct kvm_create_guest_memfd guest_memfd; > + > + r = -EFAULT; > + if (copy_from_user(&guest_memfd, argp, sizeof(guest_memfd))) > + goto out; > + > + r = kvm_gmem_create(kvm, &guest_memfd); > + break; > + } Does it need a new CAP to indicate the support of guest_memfd? This is patch series introduces 3 new CAPs and it seems any one of them can serve as the indicator of guest_memfd. +#define KVM_CAP_USER_MEMORY2 230 +#define KVM_CAP_MEMORY_ATTRIBUTES 231 +#define KVM_CAP_VM_TYPES 232 or we just go and try the ioctl, the return value will tell the result? _______________________________________________ linux-arm-kernel mailing list linux-arm-kernel@lists.infradead.org http://lists.infradead.org/mailman/listinfo/linux-arm-kernel