diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-20 18:34:50 +0100 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2020-03-20 18:47:52 +0100 |
| commit | 2da1ed62d55c6cbebbdee924f6af4e87bb6666e5 (patch) | |
| tree | 6d56bcc69e4cdde9b8ba48197b5f11492f32cc9f /arch | |
| parent | KVM: x86: remove bogus user-triggerable WARN_ON (diff) | |
| download | linux-2da1ed62d55c6cbebbdee924f6af4e87bb6666e5.tar.xz linux-2da1ed62d55c6cbebbdee924f6af4e87bb6666e5.zip | |
KVM: SVM: document KVM_MEM_ENCRYPT_OP, let userspace detect if SEV is available
Userspace has no way to query if SEV has been disabled with the
sev module parameter of kvm-amd.ko. Actually it has one, but it
is a hack: do ioctl(KVM_MEM_ENCRYPT_OP, NULL) and check if it
returns EFAULT. Make it a little nicer by returning zero for
SEV enabled and NULL argument, and while at it document the
ioctl arguments.
Cc: Brijesh Singh <brijesh.singh@amd.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/kvm/svm.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/arch/x86/kvm/svm.c b/arch/x86/kvm/svm.c index 91000501756e..f0aa9ff9666f 100644 --- a/arch/x86/kvm/svm.c +++ b/arch/x86/kvm/svm.c @@ -7158,6 +7158,9 @@ static int svm_mem_enc_op(struct kvm *kvm, void __user *argp) if (!svm_sev_enabled()) return -ENOTTY; + if (!argp) + return 0; + if (copy_from_user(&sev_cmd, argp, sizeof(struct kvm_sev_cmd))) return -EFAULT; |