[Qemu-devel] [PATCH v1 for-2.12 6/9] s390x/tcg: Implement SIGA instruction

[David Hildenbrand <david@redhat.com>]

I have no idea what that instruction does, but KVM seems to suppress it,
setting cc=3 (and as it seems to be an io instruction, it should be
protected). Let's do the same for TCG, so we're at least equal.

(it is used in the kernel for qdio, I wasn't even able to find the real
 name of that instruction)

Signed-off-by: David Hildenbrand <david@redhat.com>
---
 target/s390x/insn-data.def | 1 +
 target/s390x/translate.c   | 8 ++++++++
 2 files changed, 9 insertions(+)

diff --git a/target/s390x/insn-data.def b/target/s390x/insn-data.def
index c7353e7f11..f7b66b0091 100644
--- a/target/s390x/insn-data.def
+++ b/target/s390x/insn-data.def
@@ -1056,6 +1056,7 @@
     C(0xb238, RSCH,    S,     Z,   0, 0, 0, 0, rsch, 0)
     C(0xb237, SAL,     S,     Z,   0, 0, 0, 0, sal, 0)
     C(0xb23c, SCHM,    S,     Z,   0, insn, 0, 0, schm, 0)
+    C(0xb274, SIGA,    S,     Z,   0, 0, 0, 0, siga, 0)
     C(0xb23a, STCPS,   S,     Z,   0, 0, 0, 0, stcps, 0)
     C(0xb233, SSCH,    S,     Z,   0, insn, 0, 0, ssch, 0)
     C(0xb239, STCRW,   S,     Z,   0, insn, 0, 0, stcrw, 0)
diff --git a/target/s390x/translate.c b/target/s390x/translate.c
index 5c2432678c..1e4079464a 100644
--- a/target/s390x/translate.c
+++ b/target/s390x/translate.c
@@ -4102,6 +4102,14 @@ static ExitStatus op_schm(DisasContext *s, DisasOps *o)
     return NO_EXIT;
 }
 
+static ExitStatus op_siga(DisasContext *s, DisasOps *o)
+{
+    check_privileged(s);
+    /* From KVM code: Not provided, set CC = 3 for subchannel not operational */
+    gen_op_movi_cc(s, 3);
+    return NO_EXIT;
+}
+
 static ExitStatus op_stcps(DisasContext *s, DisasOps *o)
 {
     check_privileged(s);
-- 
2.14.3