Make s390x stopping mechanism work

qemu/s390x.h

@@ -1277,4 +1277,5 @@
 #define gen_helper_vfp_set_fpscr gen_helper_vfp_set_fpscr_s390x
 #define gen_helper_cpsr_read gen_helper_cpsr_read_s390x
 #define gen_helper_cpsr_write gen_helper_cpsr_write_s390x
+#define helper_uc_s390x_exit helper_uc_s390x_exit_s390x
 #endif

qemu/target/s390x/excp_helper.c

@@ -598,3 +598,12 @@ void s390x_cpu_do_unaligned_access(CPUState *cs, vaddr addr,
 
     tcg_s390_program_interrupt(env, PGM_SPECIFICATION, retaddr);
 }
+
+void helper_uc_s390x_exit(CPUS390XState *env)
+{
+    CPUState *cs = env_cpu(env);
+
+    cs->exception_index = EXCP_HLT;
+    cs->halted = 1;
+    cpu_loop_exit(cs);
+}

qemu/target/s390x/helper.h

@@ -1,5 +1,6 @@
 DEF_HELPER_4(uc_tracecode, void, i32, i32, ptr, i64)
 DEF_HELPER_6(uc_traceopcode, void, ptr, i64, i64, i32, ptr, i64)
+DEF_HELPER_1(uc_s390x_exit, void, env)
 
 DEF_HELPER_2(exception, noreturn, env, i32)
 DEF_HELPER_2(data_exception, noreturn, env, i32)

qemu/target/s390x/translate.c

@@ -6652,6 +6652,9 @@ static DisasJumpType translate_one(CPUS390XState *env, DisasContext *s)
     /* Search for the insn in the table.  */
     insn = extract_insn(env, s);
 
+    /* Emit insn_start now that we know the ILEN.  */
+    tcg_gen_insn_start(tcg_ctx, s->base.pc_next, s->cc_op, s->ilen);
+
     // Unicorn: trace this instruction on request
     if (HOOK_EXISTS_BOUNDED(s->uc, UC_HOOK_CODE, s->base.pc_next)) {
         gen_uc_tracecode(tcg_ctx, s->ilen, UC_HOOK_CODE_IDX, s->uc, s->base.pc_next);
@@ -6659,9 +6662,6 @@ static DisasJumpType translate_one(CPUS390XState *env, DisasContext *s)
         check_exit_request(tcg_ctx);
     }
 
-    /* Emit insn_start now that we know the ILEN.  */
-    tcg_gen_insn_start(tcg_ctx, s->base.pc_next, s->cc_op, s->ilen);
-
     /* Not found means unimplemented/illegal opcode.  */
     if (insn == NULL) {
         // qemu_log_mask(LOG_UNIMP, "unimplemented opcode 0x%02x%02x\n",
@@ -6867,7 +6867,8 @@ static void s390x_tr_tb_stop(DisasContextBase *dcbase, CPUState *cs)
 
     switch (dc->base.is_jmp) {
     case DISAS_UNICORN_HALT:
-        gen_exception(tcg_ctx, EXCP_PGM);
+        tcg_gen_insn_start(tcg_ctx, dc->base.pc_next, 0, 0);
+        gen_helper_uc_s390x_exit(tcg_ctx, tcg_ctx->cpu_env);
         break;
     case DISAS_GOTO_TB:
     case DISAS_NORETURN:

qemu/target/s390x/unicorn.c

@@ -38,7 +38,7 @@ static void s390_release(void *ctx)
 
     release_common(ctx);
 
-    s390_cpu_model_finalize(cpu);
+    s390_cpu_model_finalize((CPUState *)cpu);
     // TODO: Anymore to free?
 }
 

samples/sample_s390x.c

@@ -65,7 +65,8 @@ static void test_s390x(void)
     // finishing all the code.
     err = uc_emu_start(uc, ADDRESS, ADDRESS + sizeof(S390X_CODE) - 1, 0, 0);
     if (err) {
-        printf("Failed on uc_emu_start() with error returned: %u\n", err);
+        printf("Failed on uc_emu_start() with error returned: %u (%s)\n", err,
+               uc_strerror(err));
     }
 
     // now print out some registers

symbols.sh

@@ -6271,6 +6271,9 @@ ppc_irq_reset \
 
 ppc64_SYMBOLS=${ppc_SYMBOLS}
 
+s390x_SYMBOLS="helper_uc_s390x_exit \
+"
+
 ARCHS="x86_64 arm armeb aarch64 aarch64eb riscv32 riscv64 mips mipsel mips64 mips64el sparc sparc64 m68k ppc ppc64 s390x"
 
 for arch in $ARCHS; do