remove redundant g_debug_interrupt_sp

Author: orenc17

core/debug/src/core_armv7m/debug_box_armv7m.c

@@ -48,9 +48,6 @@ void debug_deprivilege_and_return(void * debug_handler, void * return_handler,
         xpsr = vmpu_unpriv_uint32_read((uint32_t) xpsr_p);
     }
 
-    /* FIXME: This makes the debug box overwrite the top of the interrupt stack! */
-    g_context_current_states[dst_id].sp = g_debug_interrupt_sp[dst_id];
-
     /* Destination box: Forge the destination stack frame. */
     /* Note: We manually have to set the 4 parameters on the destination stack,
      *       so we will set the API to have nargs=0. */

core/debug/src/debug_box.c

@@ -45,12 +45,10 @@ uint32_t debug_get_version(void)
     return 0;
 }
 
-uint32_t g_debug_interrupt_sp[UVISOR_MAX_BOXES];
-
 void debug_halt_error(THaltError reason, const THaltInfo *halt_info)
 {
     static int debugged_once_before = 0;
-    void *info = NULL;
+    THaltInfo * dst_halt_info = NULL;
 
     /* If the debug box does not exist (or it has not been initialized yet), or
      * the debug box was already called once, just loop forever. */
@@ -62,16 +60,20 @@ void debug_halt_error(THaltError reason, const THaltInfo *halt_info)
 
         /* Place the halt info on the interrupt stack. */
         if (halt_info) {
-            g_debug_interrupt_sp[g_debug_box.box_id] -= sizeof(THaltInfo);
-            info = (void *)g_debug_interrupt_sp[g_debug_box.box_id];
-            memcpy(info, halt_info, sizeof(THaltInfo));
+            dst_halt_info = (THaltInfo *)(g_context_current_states[g_debug_box.box_id].sp - sizeof(*halt_info));
+            if (vmpu_buffer_access_is_ok(g_debug_box.box_id, dst_halt_info, sizeof(*halt_info))) {
+                g_context_current_states[g_debug_box.box_id].sp -= sizeof(*halt_info);
+                memcpy(dst_halt_info, halt_info, sizeof(*halt_info));
+            } else {
+                while(1);
+            }
         }
 
         /* The following arguments are passed to the destination function:
          *   1. reason
          *   2. halt info
          * Upon return from the debug handler, the system will die. */
-        debug_deprivilege_and_return(g_debug_box.driver->halt_error, debug_die, reason, (uint32_t)info, 0, 0);
+        debug_deprivilege_and_return(g_debug_box.driver->halt_error, debug_die, reason, (uint32_t)dst_halt_info, 0, 0);
     }
 }
 
@@ -107,11 +109,6 @@ void debug_register_driver(const TUvisorDebugDriver * const driver)
         }
     }
 
-    for (int ii = 0; ii < UVISOR_MAX_BOXES; ii++)
-    {
-        g_debug_interrupt_sp[ii] = g_context_current_states[ii].sp;
-    }
-
     /* Register the debug box.
      * The caller of this function is considered the owner of the debug box. */
     g_debug_box.driver = driver;