From 9809f1ff6600466da3f96fb304791201c54b34fc Mon Sep 17 00:00:00 2001
From: Simon Goldschmidt <goldsimon@gmx.de>
Date: Wed, 24 Apr 2013 21:38:01 +0200
Subject: [PATCH] Fixed bug #38586

---
 CHANGELOG        | 3 +++
 src/core/netif.c | 4 ++--
 2 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/CHANGELOG b/CHANGELOG
index 685b5687..3f75c1ae 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -80,6 +80,9 @@ HISTORY
 
  ++ Bugfixes:
 
+  2013-04-24: Simon Goldschmidt (patch by Emil Ljungdahl):
+  * netif.c: fixed bug #38586 netif_loop_output() "deadlocks"
+
   2013-01-15: Simon Goldschmidt
   * ip4.c: fixed bug #37665 ip_canforward operates on address in wrong byte order
 
diff --git a/src/core/netif.c b/src/core/netif.c
index f8133f76..e7a87c3c 100644
--- a/src/core/netif.c
+++ b/src/core/netif.c
@@ -719,7 +719,7 @@ netif_loop_output(struct netif *netif, struct pbuf *p,
   for (last = r; last->next != NULL; last = last->next);
 
   SYS_ARCH_PROTECT(lev);
-  if(netif->loop_first != NULL) {
+  if (netif->loop_first != NULL) {
     LWIP_ASSERT("if first != NULL, last must also be != NULL", netif->loop_last != NULL);
     netif->loop_last->next = r;
     netif->loop_last = last;
@@ -735,7 +735,7 @@ netif_loop_output(struct netif *netif, struct pbuf *p,
 
 #if LWIP_NETIF_LOOPBACK_MULTITHREADING
   /* For multithreading environment, schedule a call to netif_poll */
-  tcpip_callback((tcpip_callback_fn)netif_poll, netif);
+  tcpip_callback_with_block((tcpip_callback_fn)netif_poll, netif, 0);
 #endif /* LWIP_NETIF_LOOPBACK_MULTITHREADING */
 
   return ERR_OK;