From 38af7001b6415e5c84019e9fdb33959634f93ef8 Mon Sep 17 00:00:00 2001
From: yintao <yintao@xiaomi.com>
Date: Fri, 14 Jun 2024 14:03:15 +0800
Subject: [PATCH] drivers/rpmsg: fix the race condtion about
 rpmsg_device_created

xxx_rpmsg_device_created may be called repeatedly.

rptun thread				app thread

rptun_dev_start				xxx_rpmsg_init

...					rpmsg_register_callback
priv->...= rpmsg_ns_unbind;
priv->..= rptun_notify_wait;
					if (ns_unbind_cb)
(switch app thread)				device_created()
						xxx_rpmsg_device_created

					metal_list_add_tail(g_cb);
...
rpmsg_device_created();
	cb->device_created
	xxx_rpmsg_device_created;

Signed-off-by: yintao <yintao@xiaomi.com>
---
 drivers/rpmsg/rpmsg.c       | 5 +++--
 include/nuttx/rpmsg/rpmsg.h | 1 +
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/rpmsg/rpmsg.c b/drivers/rpmsg/rpmsg.c
index 5adab0d869e..132cdb87fc3 100644
--- a/drivers/rpmsg/rpmsg.c
+++ b/drivers/rpmsg/rpmsg.c
@@ -229,7 +229,7 @@ int rpmsg_register_callback(FAR void *priv,
       FAR struct rpmsg_s *rpmsg =
         metal_container_of(node, struct rpmsg_s, node);
 
-      if (rpmsg->rdev->ns_unbind_cb == NULL)
+      if (!rpmsg->init)
         {
           continue;
         }
@@ -307,7 +307,7 @@ void rpmsg_unregister_callback(FAR void *priv,
           FAR struct rpmsg_s *rpmsg =
             metal_container_of(pnode, struct rpmsg_s, node);
 
-          if (rpmsg->rdev->ns_unbind_cb)
+          if (rpmsg->init)
             {
               device_destroy(rpmsg->rdev, priv);
             }
@@ -397,6 +397,7 @@ void rpmsg_device_created(FAR struct rpmsg_s *rpmsg)
         }
     }
 
+  rpmsg->init = true;
   nxrmutex_unlock(&g_rpmsg_lock);
 
 #ifdef CONFIG_RPMSG_PING
diff --git a/include/nuttx/rpmsg/rpmsg.h b/include/nuttx/rpmsg/rpmsg.h
index c8be7e01480..1964a7fcb4b 100644
--- a/include/nuttx/rpmsg/rpmsg.h
+++ b/include/nuttx/rpmsg/rpmsg.h
@@ -47,6 +47,7 @@
 
 struct rpmsg_s
 {
+  bool                         init;
   struct metal_list            bind;
   rmutex_t                     lock;
   struct metal_list            node;