x86: Unbreak TCG support for hardware breakpoints

Commit 83f338f73e broke x86 hardware breakpoint emulation by moving the
debug exception handling out of cpu_exec. Fix this by moving all TCG
related bits back, only leaving the generic guest debugging parts in
cpus.c.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
CC: TeLeMan <geleman@gmail.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>

2 files changed, 30 insertions, 24 deletions

diff --git a/cpu-exec.c b/cpu-exec.c
index 34eaedc..5cc9379 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -196,6 +196,30 @@ static inline TranslationBlock *tb_find_fast(void)
     return tb;
 }
 
+static CPUDebugExcpHandler *debug_excp_handler;
+
+CPUDebugExcpHandler *cpu_set_debug_excp_handler(CPUDebugExcpHandler *handler)
+{
+    CPUDebugExcpHandler *old_handler = debug_excp_handler;
+
+    debug_excp_handler = handler;
+    return old_handler;
+}
+
+static void cpu_handle_debug_exception(CPUState *env)
+{
+    CPUWatchpoint *wp;
+
+    if (!env->watchpoint_hit) {
+        QTAILQ_FOREACH(wp, &env->watchpoints, entry) {
+            wp->flags &= ~BP_WATCHPOINT_HIT;
+        }
+    }
+    if (debug_excp_handler) {
+        debug_excp_handler(env);
+    }
+}
+
 /* main execution loop */
 
 volatile sig_atomic_t exit_request;
@@ -269,6 +293,9 @@ int cpu_exec(CPUState *env1)
                 if (env->exception_index >= EXCP_INTERRUPT) {
                     /* exit request from the cpu execution loop */
                     ret = env->exception_index;
+                    if (ret == EXCP_DEBUG) {
+                        cpu_handle_debug_exception(env);
+                    }
                     break;
                 } else {
 #if defined(CONFIG_USER_ONLY)
diff --git a/cpus.c b/cpus.c
index 26e5bba..975a6ce 100644
--- a/cpus.c
+++ b/cpus.c
@@ -166,29 +166,8 @@ static bool all_cpu_threads_idle(void)
     return true;
 }
 
-static CPUDebugExcpHandler *debug_excp_handler;
-
-CPUDebugExcpHandler *cpu_set_debug_excp_handler(CPUDebugExcpHandler *handler)
-{
-    CPUDebugExcpHandler *old_handler = debug_excp_handler;
-
-    debug_excp_handler = handler;
-    return old_handler;
-}
-
-static void cpu_handle_debug_exception(CPUState *env)
+static void cpu_handle_guest_debug(CPUState *env)
 {
-    CPUWatchpoint *wp;
-
-    if (!env->watchpoint_hit) {
-        QTAILQ_FOREACH(wp, &env->watchpoints, entry) {
-            wp->flags &= ~BP_WATCHPOINT_HIT;
-        }
-    }
-    if (debug_excp_handler) {
-        debug_excp_handler(env);
-    }
-
     gdb_set_stop_cpu(env);
     qemu_system_debug_request();
 #ifdef CONFIG_IOTHREAD
@@ -818,7 +797,7 @@ static void *qemu_kvm_cpu_thread_fn(void *arg)
         if (cpu_can_run(env)) {
             r = kvm_cpu_exec(env);
             if (r == EXCP_DEBUG) {
-                cpu_handle_debug_exception(env);
+                cpu_handle_guest_debug(env);
             }
         }
         qemu_kvm_wait_io_event(env);
@@ -1110,7 +1089,7 @@ bool cpu_exec_all(void)
                 r = tcg_cpu_exec(env);
             }
             if (r == EXCP_DEBUG) {
-                cpu_handle_debug_exception(env);
+                cpu_handle_guest_debug(env);
                 break;
             }
         } else if (env->stop || env->stopped) {