On Tue, 16 Jun 2020 15:26:36 -0600
Alex Williamson <alex.williamson@xxxxxxxxxx> wrote:
> The next use of the device will generate an underflow from the
> stale reference.
>
> Cc: Qian Cai <cai@xxxxxx>
> Fixes: 1518ac272e78 ("vfio/pci: fix memory leaks of eventfd ctx")
> Reported-by: Daniel Wagner <dwagner@xxxxxxx>
> Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
> ---
> drivers/vfio/pci/vfio_pci.c | 8 ++++++--
> 1 file changed, 6 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/vfio/pci/vfio_pci.c b/drivers/vfio/pci/vfio_pci.c
> index 7c0779018b1b..f634c81998bb 100644
> --- a/drivers/vfio/pci/vfio_pci.c
> +++ b/drivers/vfio/pci/vfio_pci.c
> @@ -521,10 +521,14 @@ static void vfio_pci_release(void *device_data)
> vfio_pci_vf_token_user_add(vdev, -1);
> vfio_spapr_pci_eeh_release(vdev->pdev);
> vfio_pci_disable(vdev);
> - if (vdev->err_trigger)
> + if (vdev->err_trigger) {
> eventfd_ctx_put(vdev->err_trigger);
> - if (vdev->req_trigger)
> + vdev->err_trigger = NULL;
> + }
> + if (vdev->req_trigger) {
> eventfd_ctx_put(vdev->req_trigger);
> + vdev->req_trigger = NULL;
> + }
> }
>
> mutex_unlock(&vdev->reflck->lock);
>
Clearing this seems like the right thing to do.
Reviewed-by: Cornelia Huck <cohuck@xxxxxxxxxx>
