[Qemu-devel] [PATCH v1 3/3] s390x/cpumodel: allow to enable MVCOS for qemu cpu model

[David Hildenbrand <david@redhat.com>]

This allows botting a recent linux kernel (e.g. compiled for z900) and
using mvcos for uaccess:

qemu-system-s390x ... -cpu qemu,mvcos=on ...

While at it, correctly fake its abscence.

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 target/s390x/cpu_models.c | 1 +
 target/s390x/mem_helper.c | 3 +++
 2 files changed, 4 insertions(+)

diff --git a/target/s390x/cpu_models.c b/target/s390x/cpu_models.c
index c508ae1..348e760 100644
--- a/target/s390x/cpu_models.c
+++ b/target/s390x/cpu_models.c
@@ -682,6 +682,7 @@ static void add_qemu_cpu_model_features(S390FeatBitmap fbm)
         S390_FEAT_LONG_DISPLACEMENT_FAST,
         S390_FEAT_ETF2_ENH,
         S390_FEAT_STORE_CLOCK_FAST,
+        S390_FEAT_MOVE_WITH_OPTIONAL_SPEC,
         S390_FEAT_GENERAL_INSTRUCTIONS_EXT,
         S390_FEAT_EXECUTE_EXT,
         S390_FEAT_STFLE_45,
diff --git a/target/s390x/mem_helper.c b/target/s390x/mem_helper.c
index cb27465..e0a5de0 100644
--- a/target/s390x/mem_helper.c
+++ b/target/s390x/mem_helper.c
@@ -1508,6 +1508,9 @@ uint32_t HELPER(mvcos)(CPUS390XState *env, uint64_t dest, uint64_t src,
     HELPER_LOG("%s dest %" PRIx64 ", src %" PRIx64 ", len %" PRIx64 "\n",
                __func__, dest, src, len);
 
+    if (!s390_has_feat(S390_FEAT_MOVE_WITH_OPTIONAL_SPEC)) {
+        program_interrupt(env, PGM_OPERATION, 6);
+    }
     if (!(env->psw.mask & PSW_MASK_DAT)) {
         program_interrupt(env, PGM_SPECIAL_OP, 6);
     }
-- 
2.9.3