apic: add support for x2APIC mode

This commit extends the APIC ID to 32-bit long and remove the 255 max APIC
ID limit in userspace APIC. The array that manages local APICs is now
dynamically allocated based on the max APIC ID of created x86 machine.
Also, new x2APIC IPI destination determination scheme, self IPI and x2APIC
mode register access are supported.

Signed-off-by: Bui Quang Minh <minhquangbui99@gmail.com>
Message-Id: <20240111154404.5333-3-minhquangbui99@gmail.com>
Acked-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

hw/i386/x86.c

@@ -137,7 +137,7 @@ void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
      * a literal `0` in configurations where kvm_* aren't defined)
      */
     if (kvm_enabled() && x86ms->apic_id_limit > 255 &&
-        (!kvm_irqchip_in_kernel() || !kvm_enable_x2apic())) {
+        kvm_irqchip_in_kernel() && !kvm_enable_x2apic()) {
         error_report("current -smp configuration requires kernel "
                      "irqchip and X2APIC API support.");
         exit(EXIT_FAILURE);
@@ -147,6 +147,10 @@ void x86_cpus_init(X86MachineState *x86ms, int default_cpu_version)
         kvm_set_max_apic_id(x86ms->apic_id_limit);
     }
 
+    if (!kvm_irqchip_in_kernel()) {
+        apic_set_max_apic_id(x86ms->apic_id_limit);
+    }
+
     possible_cpus = mc->possible_cpu_arch_ids(ms);
     for (i = 0; i < ms->smp.cpus; i++) {
         x86_cpu_new(x86ms, possible_cpus->cpus[i].arch_id, &error_fatal);