[PATCH] rpmsg: smd: do not use mananged resources for endpoints and channels

[Srinivas Kandagatla]

All the managed resources would be freed by the time release function
is invoked. Handling such memory in qcom_smd_edge_release() would do
bad things.

Found this issue while testing Audio usecase where the dsp is started up
and shutdown in a loop.

This patch fixes this issue by using simple kzalloc for allocating
channel->name and channel which is then freed in qcom_smd_edge_release().

Without this patch restarting a remoteproc would crash the system.
Fixes: 53e2822e56c7 ("rpmsg: Introduce Qualcomm SMD backend")
Cc: <stable@xxxxxxxxxxxxxxx>
Signed-off-by: Srinivas Kandagatla <srinivas.kandagatla@xxxxxxxxxx>
---
 drivers/rpmsg/qcom_smd.c | 18 ++++++++++--------
 1 file changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index 5ce9bf7b897d..49d3838dfc3d 100644
--- a/drivers/rpmsg/qcom_smd.c
+++ b/drivers/rpmsg/qcom_smd.c
@@ -1100,12 +1100,12 @@ static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *ed
 	void *info;
 	int ret;
 
-	channel = devm_kzalloc(&edge->dev, sizeof(*channel), GFP_KERNEL);
+	channel = kzalloc(sizeof(*channel), GFP_KERNEL);
 	if (!channel)
 		return ERR_PTR(-ENOMEM);
 
 	channel->edge = edge;
-	channel->name = devm_kstrdup(&edge->dev, name, GFP_KERNEL);
+	channel->name = kstrdup(name, GFP_KERNEL);
 	if (!channel->name)
 		return ERR_PTR(-ENOMEM);
 
@@ -1156,8 +1156,8 @@ static struct qcom_smd_channel *qcom_smd_create_channel(struct qcom_smd_edge *ed
 	return channel;
 
 free_name_and_channel:
-	devm_kfree(&edge->dev, channel->name);
-	devm_kfree(&edge->dev, channel);
+	kfree(channel->name);
+	kfree(channel);
 
 	return ERR_PTR(ret);
 }
@@ -1380,11 +1380,13 @@ static void qcom_smd_edge_release(struct device *dev)
 {
 	struct qcom_smd_channel *channel;
 	struct qcom_smd_edge *edge = to_smd_edge(dev);
+	struct list_head *this, *tmp;
 
-	list_for_each_entry(channel, &edge->channels, list) {
-		SET_RX_CHANNEL_INFO(channel, state, SMD_CHANNEL_CLOSED);
-		SET_RX_CHANNEL_INFO(channel, head, 0);
-		SET_RX_CHANNEL_INFO(channel, tail, 0);
+	list_for_each_safe(this, tmp, &edge->channels) {
+		channel = list_entry(this, struct qcom_smd_channel, list);
+		list_del(&channel->list);
+		kfree(channel->name);
+		kfree(channel);
 	}
 
 	kfree(edge);
-- 
2.16.2