[PATCH v2] rpmsg: smd: do not use mananged resources for endpoints and channels

From: Srinivas Kandagatla
Date: Mon Jun 04 2018 - 05:41:17 EST


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, 9 insertions(+), 9 deletions(-)

diff --git a/drivers/rpmsg/qcom_smd.c b/drivers/rpmsg/qcom_smd.c
index 5ce9bf7b897d..f63adcd95eb0 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);
}
@@ -1378,13 +1378,13 @@ static int qcom_smd_parse_edge(struct device *dev,
*/
static void qcom_smd_edge_release(struct device *dev)
{
- struct qcom_smd_channel *channel;
+ struct qcom_smd_channel *channel, *tmp;
struct qcom_smd_edge *edge = to_smd_edge(dev);

- 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_entry_safe(channel, tmp, &edge->channels, list) {
+ list_del(&channel->list);
+ kfree(channel->name);
+ kfree(channel);
}

kfree(edge);
--
2.16.2