On Wed, Mar 15, 2023 at 11:39:32AM -0400, Tony Krowiak wrote:
> The device release callback function invoked to release the matrix device
> uses the dev_get_drvdata(device *dev) function to retrieve the
> pointer to the vfio_matrix_dev object in order to free its storage. The
> problem is, this object is not stored as drvdata with the device; since the
> kfree function will accept a NULL pointer, the memory for the
> vfio_matrix_dev object is never freed.
>
> Since the device being released is contained within the vfio_matrix_dev
> object, the container_of macro will be used to retrieve its pointer.
>
> Fixes: 1fde573413b5 ("s390: vfio-ap: base implementation of VFIO AP device driver")
> Signed-off-by: Tony Krowiak <akrowiak@xxxxxxxxxxxxx>
> ---
> drivers/s390/crypto/vfio_ap_drv.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/s390/crypto/vfio_ap_drv.c b/drivers/s390/crypto/vfio_ap_drv.c
> index 997b524bdd2b..15e9de9f4574 100644
> --- a/drivers/s390/crypto/vfio_ap_drv.c
> +++ b/drivers/s390/crypto/vfio_ap_drv.c
> @@ -54,8 +54,9 @@ static struct ap_driver vfio_ap_drv = {
>
> static void vfio_ap_matrix_dev_release(struct device *dev)
> {
> - struct ap_matrix_dev *matrix_dev = dev_get_drvdata(dev);
> -
> + struct ap_matrix_dev *matrix_dev = container_of(dev,
> + struct ap_matrix_dev,
> + device);
> kfree(matrix_dev);
Could you keep this code more readable, including adding the missing
blank line after the declaration, please? Something like:
static void vfio_ap_matrix_dev_release(struct device *dev)
{
struct ap_matrix_dev *matrix_dev;
matrix_dev = container_of(dev, struct ap_matrix_dev, device);
kfree(matrix_dev);
}
Thanks!
