From d30d9ee94cc0e7ae91da7251d9c280b8cf7e5e4d Mon Sep 17 00:00:00 2001 From: Tom Dohrmann Date: Mon, 2 Sep 2024 14:42:19 +0000 Subject: [PATCH] KVM: x86: Only advertise KVM_CAP_READONLY_MEM when supported by VM Until recently, KVM_CAP_READONLY_MEM was unconditionally supported on x86, but this is no longer the case for SEV-ES and SEV-SNP VMs. When KVM_CHECK_EXTENSION is invoked on a VM, only advertise KVM_CAP_READONLY_MEM when it's actually supported. Fixes: 66155de93bcf ("KVM: x86: Disallow read-only memslots for SEV-ES and SEV-SNP (and TDX)") Cc: Sean Christopherson Cc: Paolo Bonzini Cc: Michael Roth Signed-off-by: Tom Dohrmann Message-ID: <20240902144219.3716974-1-erbse.13@gmx.de> Signed-off-by: Paolo Bonzini --- arch/x86/kvm/x86.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/arch/x86/kvm/x86.c b/arch/x86/kvm/x86.c index 2c7327ef0f0d0..0f801804150e7 100644 --- a/arch/x86/kvm/x86.c +++ b/arch/x86/kvm/x86.c @@ -4656,7 +4656,6 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_ASYNC_PF_INT: case KVM_CAP_GET_TSC_KHZ: case KVM_CAP_KVMCLOCK_CTRL: - case KVM_CAP_READONLY_MEM: case KVM_CAP_IOAPIC_POLARITY_IGNORED: case KVM_CAP_TSC_DEADLINE_TIMER: case KVM_CAP_DISABLE_QUIRKS: @@ -4815,6 +4814,8 @@ int kvm_vm_ioctl_check_extension(struct kvm *kvm, long ext) case KVM_CAP_VM_TYPES: r = kvm_caps.supported_vm_types; break; + case KVM_CAP_READONLY_MEM: + r = kvm ? kvm_arch_has_readonly_mem(kvm) : 1; default: break; }