diff mbox series

[v6,38/60] i386/tdx: Disable SMM for TDX VMs

Message ID 20241105062408.3533704-39-xiaoyao.li@intel.com (mailing list archive)
State New
Headers show
Series QEMU TDX support | expand

Commit Message

Xiaoyao Li Nov. 5, 2024, 6:23 a.m. UTC 
TDX doesn't support SMM and VMM cannot emulate SMM for TDX VMs because
VMM cannot manipulate TDX VM's memory.

Disable SMM for TDX VMs and error out if user requests to enable SMM.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
---
 target/i386/kvm/tdx.c | 9 +++++++++
 1 file changed, 9 insertions(+)
diff mbox series

Patch

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 00faffa891e4..68d90a180db7 100644
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -355,11 +355,20 @@  static Notifier tdx_machine_done_notify = {
 
 static int tdx_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
 {
+    MachineState *ms = MACHINE(qdev_get_machine());
+    X86MachineState *x86ms = X86_MACHINE(ms);
     TdxGuest *tdx = TDX_GUEST(cgs);
     int r = 0;
 
     kvm_mark_guest_state_protected();
 
+    if (x86ms->smm == ON_OFF_AUTO_AUTO) {
+        x86ms->smm = ON_OFF_AUTO_OFF;
+    } else if (x86ms->smm == ON_OFF_AUTO_ON) {
+        error_setg(errp, "TDX VM doesn't support SMM");
+        return -EINVAL;
+    }
+
     if (!tdx_caps) {
         r = get_tdx_capabilities(errp);
         if (r) {