target/s390x: rework PGM interrupt psw.addr handling

We can tell from the program interrupt code, whether a program interrupt
has to forward the address in the PGM new PSW
(suppressing/terminated/completed) to point at the next instruction, or
if it is nullifying and the PSW address does not have to be incremented.

So let's not modify the PSW address outside of the injection path and
handle this internally. We just have to handle instruction length
auto detection if no valid instruction length can be provided.

This should fix various program interrupt injection paths, where the
PSW was not properly forwarded.

Signed-off-by: David Hildenbrand <david@redhat.com>
Message-Id: <20170609142156.18767-3-david@redhat.com>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 8 insertions, 13 deletions

diff --git a/target/s390x/misc_helper.c b/target/s390x/misc_helper.c
index d6eda832eb..4daa01632e 100644
--- a/target/s390x/misc_helper.c
+++ b/target/s390x/misc_helper.c
@@ -54,19 +54,14 @@ void QEMU_NORETURN runtime_exception(CPUS390XState *env, int excp,
                                      uintptr_t retaddr)
 {
     CPUState *cs = CPU(s390_env_get_cpu(env));
-    int t;
 
     cs->exception_index = EXCP_PGM;
     env->int_pgm_code = excp;
+    env->int_pgm_ilen = ILEN_AUTO;
 
     /* Use the (ultimate) callers address to find the insn that trapped.  */
     cpu_restore_state(cs, retaddr);
 
-    /* Advance past the insn.  */
-    t = cpu_ldub_code(env, env->psw.addr);
-    env->int_pgm_ilen = t = get_ilen(t);
-    env->psw.addr += t;
-
     cpu_loop_exit(cs);
 }
 
@@ -199,12 +194,12 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1, uint64_t r3)
     IplParameterBlock *iplb;
 
     if (env->psw.mask & PSW_MASK_PSTATE) {
-        program_interrupt(env, PGM_PRIVILEGED, ILEN_LATER_INC);
+        program_interrupt(env, PGM_PRIVILEGED, ILEN_AUTO);
         return;
     }
 
     if ((subcode & ~0x0ffffULL) || (subcode > 6)) {
-        program_interrupt(env, PGM_SPECIFICATION, ILEN_LATER_INC);
+        program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO);
         return;
     }
 
@@ -229,12 +224,12 @@ void handle_diag_308(CPUS390XState *env, uint64_t r1, uint64_t r3)
         break;
     case 5:
         if ((r1 & 1) || (addr & 0x0fffULL)) {
-            program_interrupt(env, PGM_SPECIFICATION, ILEN_LATER_INC);
+            program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO);
             return;
         }
         if (!address_space_access_valid(&address_space_memory, addr,
                                         sizeof(IplParameterBlock), false)) {
-            program_interrupt(env, PGM_ADDRESSING, ILEN_LATER_INC);
+            program_interrupt(env, PGM_ADDRESSING, ILEN_AUTO);
             return;
         }
         iplb = g_malloc0(sizeof(IplParameterBlock));
@@ -258,12 +253,12 @@ out:
         return;
     case 6:
         if ((r1 & 1) || (addr & 0x0fffULL)) {
-            program_interrupt(env, PGM_SPECIFICATION, ILEN_LATER_INC);
+            program_interrupt(env, PGM_SPECIFICATION, ILEN_AUTO);
             return;
         }
         if (!address_space_access_valid(&address_space_memory, addr,
                                         sizeof(IplParameterBlock), true)) {
-            program_interrupt(env, PGM_ADDRESSING, ILEN_LATER_INC);
+            program_interrupt(env, PGM_ADDRESSING, ILEN_AUTO);
             return;
         }
         iplb = s390_ipl_get_iplb();
@@ -307,7 +302,7 @@ void HELPER(diag)(CPUS390XState *env, uint32_t r1, uint32_t r3, uint32_t num)
     }
 
     if (r) {
-        program_interrupt(env, PGM_OPERATION, ILEN_LATER_INC);
+        program_interrupt(env, PGM_OPERATION, ILEN_AUTO);
     }
 }