[PATCH v2] s390x: Properly fetch the short psw on diag308 subc 0/1

[Janosch Frank <frankja@linux.ibm.com>]

We need to actually fetch the cpu mask and set it. As we invert the
short psw indication in the mask, SIE will report a specification
exception, if it wasn't present in the reset psw.

Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
---
 target/s390x/cpu.c | 12 ++++++++++--
 target/s390x/cpu.h |  1 +
 2 files changed, 11 insertions(+), 2 deletions(-)

diff --git a/target/s390x/cpu.c b/target/s390x/cpu.c
index 736a7903e2..40aa42e092 100644
--- a/target/s390x/cpu.c
+++ b/target/s390x/cpu.c
@@ -76,8 +76,16 @@ static bool s390_cpu_has_work(CPUState *cs)
 static void s390_cpu_load_normal(CPUState *s)
 {
     S390CPU *cpu = S390_CPU(s);
-    cpu->env.psw.addr = ldl_phys(s->as, 4) & PSW_MASK_ESA_ADDR;
-    cpu->env.psw.mask = PSW_MASK_32 | PSW_MASK_64;
+    uint64_t spsw = ldq_phys(s->as, 0);
+
+    cpu->env.psw.mask = spsw & 0xffffffff80000000UL;
+    /*
+     * Invert short psw indication, so SIE will report a specification
+     * exception if it was not set.
+     */
+    cpu->env.psw.mask ^= PSW_MASK_SHORTPSW;
+    cpu->env.psw.addr = spsw & 0x7fffffffUL;
+
     s390_cpu_set_state(S390_CPU_STATE_OPERATING, cpu);
 }
 #endif
diff --git a/target/s390x/cpu.h b/target/s390x/cpu.h
index 947553386f..2c687185f1 100644
--- a/target/s390x/cpu.h
+++ b/target/s390x/cpu.h
@@ -261,6 +261,7 @@ extern const struct VMStateDescription vmstate_s390_cpu;
 #define PSW_MASK_EXT            0x0100000000000000ULL
 #define PSW_MASK_KEY            0x00F0000000000000ULL
 #define PSW_SHIFT_KEY           52
+#define PSW_MASK_SHORTPSW	0x0008000000000000ULL
 #define PSW_MASK_MCHECK         0x0004000000000000ULL
 #define PSW_MASK_WAIT           0x0002000000000000ULL
 #define PSW_MASK_PSTATE         0x0001000000000000ULL
-- 
2.20.1