The nitro accel does not actually make use of CPU emulation or details:
It always uses the host CPU regardless of configuration. Machines for
the nitro accel select the host CPU type as default to have a clear
statement of the above and to have a unified cpu type across all
supported architectures.

The arm64 logic on Linux currently only allows -cpu host for KVM based
virtual machines. Add a special case for nitro so that when the nitro
accel is active, it allows use of the host cpu type.

Signed-off-by: Alexander Graf <graf@amazon.com>
---
 target/arm/cpu64.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index 5d7c6b7fbb..c01051f038 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -765,6 +765,14 @@ static void aarch64_a53_initfn(Object *obj)
 static void aarch64_host_initfn(Object *obj)
 {
     ARMCPU *cpu = ARM_CPU(obj);
+
+#if defined(CONFIG_NITRO)
+    if (nitro_enabled()) {
+        /* The nitro accel uses -cpu host, but does not actually consume it */
+        return;
+    }
+#endif
+
 #if defined(CONFIG_KVM)
     kvm_arm_set_cpu_features_from_host(cpu);
     if (arm_feature(&cpu->env, ARM_FEATURE_AARCH64)) {
-- 
2.47.1




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