kvm: Introduce kvm_arch_pre_create_vcpu()

Introduce kvm_arch_pre_create_vcpu(), to perform arch-dependent
work prior to create any vcpu. This is for i386 TDX because it needs
call TDX_INIT_VM before creating any vcpu.

The specific implementation for i386 will be added in the future patch.

Signed-off-by: Xiaoyao Li <xiaoyao.li@intel.com>
Acked-by: Gerd Hoffmann <kraxel@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
Reviewed-by: Zhao Liu <zhao1.liu@intel.com>
Link: https://lore.kernel.org/r/20250508150002.689633-8-xiaoyao.li@intel.com
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>

9 files changed, 40 insertions, 0 deletions

diff --git a/accel/kvm/kvm-all.c b/accel/kvm/kvm-all.c
index 278a50690c..42d239cf8f 100644
--- a/accel/kvm/kvm-all.c
+++ b/accel/kvm/kvm-all.c
@@ -545,6 +545,11 @@ int kvm_init_vcpu(CPUState *cpu, Error **errp)
 
     trace_kvm_init_vcpu(cpu->cpu_index, kvm_arch_vcpu_id(cpu));
 
+    ret = kvm_arch_pre_create_vcpu(cpu, errp);
+    if (ret < 0) {
+        goto err;
+    }
+
     ret = kvm_create_vcpu(cpu);
     if (ret < 0) {
         error_setg_errno(errp, -ret,
diff --git a/include/system/kvm.h b/include/system/kvm.h
index b690dda137..62ec131d4d 100644
--- a/include/system/kvm.h
+++ b/include/system/kvm.h
@@ -376,6 +376,7 @@ int kvm_arch_get_default_type(MachineState *ms);
 
 int kvm_arch_init(MachineState *ms, KVMState *s);
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp);
 int kvm_arch_init_vcpu(CPUState *cpu);
 int kvm_arch_destroy_vcpu(CPUState *cpu);
 
diff --git a/target/arm/kvm.c b/target/arm/kvm.c
index a2791aa866..74fda8b809 100644
--- a/target/arm/kvm.c
+++ b/target/arm/kvm.c
@@ -1846,6 +1846,11 @@ static int kvm_arm_sve_set_vls(ARMCPU *cpu)
 
 #define ARM_CPU_ID_MPIDR       3, 0, 0, 0, 5
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     int ret;
diff --git a/target/i386/kvm/kvm.c b/target/i386/kvm/kvm.c
index 6d88495d47..446f0600d4 100644
--- a/target/i386/kvm/kvm.c
+++ b/target/i386/kvm/kvm.c
@@ -2051,6 +2051,11 @@ full:
     abort();
 }
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     struct {
diff --git a/target/loongarch/kvm/kvm.c b/target/loongarch/kvm/kvm.c
index 1bda570482..c66bdd5302 100644
--- a/target/loongarch/kvm/kvm.c
+++ b/target/loongarch/kvm/kvm.c
@@ -1071,7 +1071,11 @@ static int kvm_cpu_check_pv_features(CPUState *cs, Error **errp)
             env->pv_features |= BIT(KVM_FEATURE_VIRT_EXTIOI);
         }
     }
+    return 0;
+}
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
     return 0;
 }
 
diff --git a/target/mips/kvm.c b/target/mips/kvm.c
index d67b7c1a8e..ec53acb51a 100644
--- a/target/mips/kvm.c
+++ b/target/mips/kvm.c
@@ -61,6 +61,11 @@ int kvm_arch_irqchip_create(KVMState *s)
     return 0;
 }
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     CPUMIPSState *env = cpu_env(cs);
diff --git a/target/ppc/kvm.c b/target/ppc/kvm.c
index 8a957c3c7d..015658049e 100644
--- a/target/ppc/kvm.c
+++ b/target/ppc/kvm.c
@@ -479,6 +479,11 @@ static void kvmppc_hw_debug_points_init(CPUPPCState *cenv)
     }
 }
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     PowerPCCPU *cpu = POWERPC_CPU(cs);
diff --git a/target/riscv/kvm/kvm-cpu.c b/target/riscv/kvm/kvm-cpu.c
index efb41fac53..e1a04be20f 100644
--- a/target/riscv/kvm/kvm-cpu.c
+++ b/target/riscv/kvm/kvm-cpu.c
@@ -1472,6 +1472,11 @@ static int kvm_vcpu_enable_sbi_dbcn(RISCVCPU *cpu, CPUState *cs)
     return kvm_set_one_reg(cs, kvm_sbi_dbcn.kvm_reg_id, &reg);
 }
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     int ret = 0;
diff --git a/target/s390x/kvm/kvm.c b/target/s390x/kvm/kvm.c
index 6cd2ebc5f1..67d9a1977c 100644
--- a/target/s390x/kvm/kvm.c
+++ b/target/s390x/kvm/kvm.c
@@ -398,6 +398,11 @@ unsigned long kvm_arch_vcpu_id(CPUState *cpu)
     return cpu->cpu_index;
 }
 
+int kvm_arch_pre_create_vcpu(CPUState *cpu, Error **errp)
+{
+    return 0;
+}
+
 int kvm_arch_init_vcpu(CPUState *cs)
 {
     unsigned int max_cpus = MACHINE(qdev_get_machine())->smp.max_cpus;