i386/tdx: Set and check kernel_irqchip mode for TDX

KVM mandates kernel_irqchip to be split mode.

Set it to split mode automatically when users don't provide an explicit
value, otherwise check it to be the split mode.

Suggested-by: Daniel P. Berrangé <berrange@redhat.com>
Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250508150002.689633-39-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

diff --git a/target/i386/kvm/tdx.c b/target/i386/kvm/tdx.c
index 32c3f3795d04b615e19e19c172b77004f8c52942..68ed3b9f98787c224f6d0d9f0cd2f0265e9b639e 100644 (file)
--- a/target/i386/kvm/tdx.c
+++ b/target/i386/kvm/tdx.c
@@ -16,6 +16,7 @@
 #include "qapi/error.h"
 #include "qom/object_interfaces.h"
 #include "crypto/hash.h"
+#include "system/kvm_int.h"
 #include "system/runstate.h"
 #include "system/system.h"
 #include "system/ramblock.h"
@@ -388,6 +389,13 @@ static int tdx_kvm_init(ConfidentialGuestSupport *cgs, Error **errp)
         return -EINVAL;
     }
 
+    if (kvm_state->kernel_irqchip_split == ON_OFF_AUTO_AUTO) {
+        kvm_state->kernel_irqchip_split = ON_OFF_AUTO_ON;
+    } else if (kvm_state->kernel_irqchip_split != ON_OFF_AUTO_ON) {
+        error_setg(errp, "TDX VM requires kernel_irqchip to be split");
+        return -EINVAL;
+    }
+
     if (!tdx_caps) {
         r = get_tdx_capabilities(errp);
         if (r) {