[RFC PATCH v3 11/19] target/arm: fix sve and pauth finalize for named cpu models

Named models provide authoritative ID-register values, so don't derive
SVE vector lengths or pauth fields from the host; require explicit SVE
lengths and leave the model's pauth fields intact.

Signed-off-by: Khushit Shah <[email protected]>
---
 target/arm/cpu64.c | 29 +++++++++++++++++++++++++++++
 1 file changed, 29 insertions(+)

diff --git a/target/arm/cpu64.c b/target/arm/cpu64.c
index cdad0fc46d..44dd9acf80 100644
--- a/target/arm/cpu64.c
+++ b/target/arm/cpu64.c
@@ -38,6 +38,7 @@
 #include "internals.h"
 #include "cpu-features.h"
 #include "cpu-idregs.h"
+#include "arm-cpu-models.h"
 #include "trace.h"
 
 /* convert between <register>_IDX and SYS_<register> */
@@ -134,6 +135,20 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
             return;
         }
 
+        /*
+         * If SVE is enabled but no vector lengths are specified, we must not
+         * default to the host's supported lengths for named CPU models, as
+         * this breaks live migration.
+         */
+        {
+            ARMCPUClass *acc = ARM_CPU_GET_CLASS(cpu);
+            if (acc->info && arm_find_model(acc->info->name)) {
+                error_setg(errp,
+                           "Named CPU models with SVE must set vector lengths");
+                return;
+            }
+        }
+
         if (kvm_enabled()) {
             /* Disabling a supported length disables all larger lengths. */
             tmp = vq_init & vq_supported;
@@ -556,6 +571,20 @@ void arm_cpu_pauth_finalize(ARMCPU *cpu, Error **errp)
     ARMISARegisters *isar = &cpu->isar;
     uint64_t isar1, isar2;
 
+    /*
+     * For named CPU models the model props write the authoritative
+     * APA/API/APA3/GPA/GPI/GPA3 values directly into cpu->isar, so do not
+     * override them here. Since other code relies on cpu->prop_pauth,
+     * mirror the resulting pauth state into prop_pauth.
+     */
+    {
+        ARMCPUClass *acc = ARM_CPU_GET_CLASS(cpu);
+        if (acc->info && arm_find_model(acc->info->name)) {
+            cpu->prop_pauth = cpu_isar_feature(aa64_pauth, cpu);
+            return;
+        }
+    }
+
     /*
      * These properties enable or disable Pauth as a whole, or change
      * the pauth algorithm, but do not change the set of features that
-- 
2.52.0