In some cases, such as if the kvm-amd "sev" module parameter is set to 0, SEV will be unavailable but query-sev-capabilities will still return all the information. This tricks libvirt into erroneously reporting that SEV is available. Check the actual usability of the feature and return the appropriate error if QEMU cannot use KVM or KVM cannot use SEV.
Signed-off-by: Paolo Bonzini <[email protected]> --- target/i386/sev.c | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/target/i386/sev.c b/target/i386/sev.c index 70f9ee026f..22194b3e32 100644 --- a/target/i386/sev.c +++ b/target/i386/sev.c @@ -450,6 +450,15 @@ sev_get_capabilities(Error **errp) uint32_t ebx; int fd; + if (!kvm_enabled()) { + error_setg(errp, "KVM not enabled\n"); + return NULL; + } + if (kvm_vm_ioctl(kvm_state, KVM_MEMORY_ENCRYPT_OP, NULL) < 0) { + error_setg(errp, "SEV is not enabled\n"); + return NULL; + } + fd = open(DEFAULT_SEV_DEVICE, O_RDWR); if (fd < 0) { error_setg_errno(errp, errno, "Failed to open %s", -- 2.26.2
