[patch] only update dcache after write succeeds

[dje@google.com (Doug Evans)]

Hi.

Marc, Greg: Can you see if this patch fixes things for you?

2009-09-14  Doug Evans  <dje@google.com>

	* target.c (memory_xfer_partial): Only update dcache after we know
	the write succeeded.

Index: target.c
===================================================================
RCS file: /cvs/src/src/gdb/target.c,v
retrieving revision 1.223
diff -u -p -r1.223 target.c
--- target.c	8 Sep 2009 23:52:45 -0000	1.223
+++ target.c	14 Sep 2009 19:11:38 -0000
@@ -1289,19 +1289,6 @@ memory_xfer_partial (struct target_ops *
 	}
     }
 
-  /* Make sure the cache gets updated no matter what - if we are writing
-     to the stack, even if this write is not tagged as such, we still need
-     to update the cache. */
-
-  if (inf != NULL
-      && readbuf == NULL
-      && !region->attrib.cache
-      && stack_cache_enabled_p
-      && object != TARGET_OBJECT_STACK_MEMORY)
-    {
-      dcache_update (target_dcache, memaddr, (void *) writebuf, reg_len);
-    }
-
   /* If none of those methods found the memory we wanted, fall back
      to a target partial transfer.  Normally a single call to
      to_xfer_partial is enough; if it doesn't recognize an object
@@ -1331,6 +1318,20 @@ memory_xfer_partial (struct target_ops *
   if (readbuf && !show_memory_breakpoints)
     breakpoint_restore_shadows (readbuf, memaddr, reg_len);
 
+  /* Make sure the cache gets updated no matter what - if we are writing
+     to the stack.  Even if this write is not tagged as such, we still need
+     to update the cache.  */
+
+  if (res > 0
+      && inf != NULL
+      && writebuf != NULL
+      && !region->attrib.cache
+      && stack_cache_enabled_p
+      && object != TARGET_OBJECT_STACK_MEMORY)
+    {
+      dcache_update (target_dcache, memaddr, (void *) writebuf, reg_len);
+    }
+
   /* If we still haven't got anything, return the last error.  We
      give up.  */
   return res;