The commit subject should start with "rpmsg: char:"
no glink driver update...
Regards,
Arnaud
On 9/12/22 19:05, Deepak Kumar Singh wrote:
> When remote host goes down glink char device channel is freed and
> associated rpdev is destroyed through rpmsg_chrdev_eptdev_destroy(),
> At the same time user space apps can still try to open/poll rpmsg
> char device which will result in calling rpmsg_create_ept()/rpmsg_poll().
> These functions will try to reference rpdev which has already been freed
> through rpmsg_chrdev_eptdev_destroy().
>
> File operation functions and device removal function must be protected
> with lock. This patch adds existing ept lock in remove function as well.
>
> Signed-off-by: Deepak Kumar Singh <quic_deesin@xxxxxxxxxxx>
> ---
> drivers/rpmsg/rpmsg_char.c | 8 ++++++++
> 1 file changed, 8 insertions(+)
>
> diff --git a/drivers/rpmsg/rpmsg_char.c b/drivers/rpmsg/rpmsg_char.c
> index 4f21891..5500dc0 100644
> --- a/drivers/rpmsg/rpmsg_char.c
> +++ b/drivers/rpmsg/rpmsg_char.c
> @@ -75,6 +75,7 @@ int rpmsg_chrdev_eptdev_destroy(struct device *dev, void *data)
> struct rpmsg_eptdev *eptdev = dev_to_eptdev(dev);
>
> mutex_lock(&eptdev->ept_lock);
> + eptdev->rpdev = NULL;
> if (eptdev->ept) {
> rpmsg_destroy_ept(eptdev->ept);
> eptdev->ept = NULL;
> @@ -126,6 +127,11 @@ static int rpmsg_eptdev_open(struct inode *inode, struct file *filp)
> return -EBUSY;
> }
>
> + if (!eptdev->rpdev) {
> + mutex_unlock(&eptdev->ept_lock);
> + return -ENETRESET;
> + }
> +
> get_device(dev);
>
> /*
> @@ -277,7 +283,9 @@ static __poll_t rpmsg_eptdev_poll(struct file *filp, poll_table *wait)
> if (!skb_queue_empty(&eptdev->queue))
> mask |= EPOLLIN | EPOLLRDNORM;
>
> + mutex_lock(&eptdev->ept_lock);
> mask |= rpmsg_poll(eptdev->ept, filp, wait);
> + mutex_unlock(&eptdev->ept_lock);
>
> return mask;
> }
