Re: [dpdk-dev] [PATCH] pci/vfio: fixup rte_intr_callback_unregister() handling

[Kevin Traynor <ktraynor@redhat.com>]

On 10/24/2018 11:11 AM, Darek Stojaczyk wrote:
> This function is documented to return the number of unregistered
> callbacks or negative numbers on error, but pci_vfio checks for
> ret != 0 to detect failures. Not anymore.
> 
> Fixes: c115fd000c32 ("vfio: handle hotplug request notifier")
> Cc: jia.guo@intel.com
> Cc: stable@dpdk.org

The Fixes: commit indicates this is not for stable, and the modified
function was added in that commit. If there is some equivalent fix for
stable, please send a backport for that.

> 
> Signed-off-by: Darek Stojaczyk <dariusz.stojaczyk@intel.com>
> ---
>  drivers/bus/pci/linux/pci_vfio.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/bus/pci/linux/pci_vfio.c b/drivers/bus/pci/linux/pci_vfio.c
> index b1f0683fe..305cc0601 100644
> --- a/drivers/bus/pci/linux/pci_vfio.c
> +++ b/drivers/bus/pci/linux/pci_vfio.c
> @@ -341,7 +341,7 @@ pci_vfio_enable_notifier(struct rte_pci_device *dev, int vfio_dev_fd)
>  		ret = rte_intr_callback_unregister(&dev->vfio_req_intr_handle,
>  						 pci_vfio_req_handler,
>  						 (void *)&dev->device);
> -		if (ret)
> +		if (ret < 0)
>  			RTE_LOG(ERR, EAL,
>  				"Fail to unregister req notifier handler.\n");
>  		goto error;
> @@ -373,7 +373,7 @@ pci_vfio_disable_notifier(struct rte_pci_device *dev)
>  	ret = rte_intr_callback_unregister(&dev->vfio_req_intr_handle,
>  					   pci_vfio_req_handler,
>  					   (void *)&dev->device);
> -	if (ret) {
> +	if (ret < 0) {
>  		RTE_LOG(ERR, EAL,
>  			 "fail to unregister req notifier handler.\n");
>  		return -1;
>