target/arm: Disable SVE extensions when SVE is disabled

Cc: [email protected]
Resolves: https://gitlab.com/qemu-project/qemu/-/issues/2304
Reported-by: Marcin Juszkiewicz <[email protected]>
Signed-off-by: Richard Henderson <[email protected]>
Signed-off-by: Marcin Juszkiewicz <[email protected]>
Message-id: [email protected]
Reviewed-by: Peter Maydell <[email protected]>
Signed-off-by: Peter Maydell <[email protected]>
(cherry picked from commit daf9748)
Signed-off-by: Michael Tokarev <[email protected]>

Author: hrw

target/arm/cpu64.c

@@ -109,7 +109,11 @@ void arm_cpu_sve_finalize(ARMCPU *cpu, Error **errp)
          * No explicit bits enabled, and no implicit bits from sve-max-vq.
          */
         if (!cpu_isar_feature(aa64_sve, cpu)) {
-            /* SVE is disabled and so are all vector lengths.  Good. */
+            /*
+             * SVE is disabled and so are all vector lengths.  Good.
+             * Disable all SVE extensions as well.
+             */
+            cpu->isar.id_aa64zfr0 = 0;
             return;
         }