Re: [STLinux Kernel] [PATCH 1/1] remoteproc: fix vdev reference management

From: Patrice Chotard
Date: Wed Jan 04 2017 - 03:13:53 EST




On 12/14/2016 04:11 PM, Loic Pallardy wrote:
> Commit 2b45cef5868a ("remoteproc: Further extend the vdev life cycle")
> extends kref support for vdev management.
> It introduces a regression when following sequence is executed:
> rproc_boot --> rproc_shutdown --> rproc_boot
> Second rproc_boot call crashes on register_virtio_device as device
> is already existing.
> Issue is previous vdev is never released when rproc is stop because
> associated refcount is too high.
>
> kref_get introduces is not needed as kref_init already initializes
> krefcount to 1 because it considers associated variable as used.
> This introduces a misalignment between kref_get and kref_put calls.
>
> Signed-off-by: Loic Pallardy <loic.pallardy@xxxxxx>
> ---
> drivers/remoteproc/remoteproc_core.c | 3 ---
> 1 file changed, 3 deletions(-)
>
> diff --git a/drivers/remoteproc/remoteproc_core.c b/drivers/remoteproc/remoteproc_core.c
> index 9a507e7..feb24c4 100644
> --- a/drivers/remoteproc/remoteproc_core.c
> +++ b/drivers/remoteproc/remoteproc_core.c
> @@ -396,9 +396,6 @@ static int rproc_handle_vdev(struct rproc *rproc, struct fw_rsc_vdev *rsc,
> goto unwind_vring_allocations;
> }
>
> - /* track the rvdevs list reference */
> - kref_get(&rvdev->refcount);
> -
> list_add_tail(&rvdev->node, &rproc->rvdevs);
>
> rproc_add_subdev(rproc, &rvdev->subdev,
>

Hi Loic

Acked-by: Patrice Chotard <patrice.chotard@xxxxxx>

Patrice