Re: [RFC PATCH v11 12/29] KVM: Add KVM_CREATE_GUEST_MEMFD ioctl() for guest-specific backing memory
From: Xiaoyao Li <hidden>
Date: 2023-07-20 14:46:31
Also in:
kvm, kvm-riscv, kvmarm, linux-arm-kernel, linux-fsdevel, linux-mips, linux-mm, linux-riscv, linux-security-module, lkml
On 7/19/2023 7:44 AM, Sean Christopherson wrote:
quoted hunk ↗ jump to hunk
@@ -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?