--- chan_sip.c （版本 1498）
+++ chan_sip.c （版本 1499）
@@ -2130,7 +2130,7 @@
 
  msg = sip_methods[sipmethod].text;
 
- ast_mutex_lock(&p->lock);
+ //ast_mutex_lock(&p->lock); //libing remove lock
  for (cur = p->packets; cur; prev = cur, cur = cur->next) {
  if ((cur->seqno == seqno) && ((ast_test_flag(cur, FLAG_RESPONSE)) == resp) &&
  ((ast_test_flag(cur, FLAG_RESPONSE)) ||
@@ -2153,7 +2153,7 @@
  break;
  }
  }
- ast_mutex_unlock(&p->lock);
+ //ast_mutex_unlock(&p->lock);
  if (option_debug)
  ast_log(LOG_DEBUG, "Stopping retransmission on '%s' of %s %d: Match %s\n", p->callid, resp ? "Response" : "Request", seqno, res ? "Not Found" : "Found");
 }
@@ -2172,7 +2172,9 @@
  }
  cur = p->packets;
  method = (cur->method) ? cur->method : find_sip_method(cur->data);
+ ast_mutex_lock(&p->lock); //libing lock
  __sip_ack(p, cur->seqno, ast_test_flag(cur, FLAG_RESPONSE), method);
+ ast_mutex_unlock(&p->lock);
  }
 }