From d1e54dd08f163a9021433020d16a8f8f70ddc41c Mon Sep 17 00:00:00 2001 From: Fuad Tabba Date: Tue, 29 Jul 2025 15:54:40 -0700 Subject: KVM: x86: Enable KVM_GUEST_MEMFD for all 64-bit builds Enable KVM_GUEST_MEMFD for all KVM x86 64-bit builds, i.e. for "default" VM types when running on 64-bit KVM. This will allow using guest_memfd to back non-private memory for all VM shapes, by supporting mmap() on guest_memfd. Opportunistically clean up various conditionals that become tautologies once x86 selects KVM_GUEST_MEMFD more broadly. Specifically, because SW protected VMs, SEV, and TDX are all 64-bit only, private memory no longer needs to take explicit dependencies on KVM_GUEST_MEMFD, because it is effectively a prerequisite. Suggested-by: Sean Christopherson Signed-off-by: Fuad Tabba Reviewed-by: Xiaoyao Li Reviewed-by: David Hildenbrand Signed-off-by: Sean Christopherson Message-ID: <20250729225455.670324-10-seanjc@google.com> Signed-off-by: Paolo Bonzini --- virt/kvm/kvm_main.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'virt') diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index aa86dfd757db..4f57cb92e109 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -1588,7 +1588,7 @@ static int check_memory_region_flags(struct kvm *kvm, { u32 valid_flags = KVM_MEM_LOG_DIRTY_PAGES; - if (kvm_arch_has_private_mem(kvm)) + if (IS_ENABLED(CONFIG_KVM_GUEST_MEMFD)) valid_flags |= KVM_MEM_GUEST_MEMFD; /* Dirty logging private memory is not currently supported. */ @@ -4917,7 +4917,7 @@ static int kvm_vm_ioctl_check_extension_generic(struct kvm *kvm, long arg) #endif #ifdef CONFIG_KVM_GUEST_MEMFD case KVM_CAP_GUEST_MEMFD: - return !kvm || kvm_arch_has_private_mem(kvm); + return 1; #endif default: break; -- cgit v1.2.3