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Subject: Re: [PATCH 5/8] vfio/mdev: Avoid masking error code to EBUSY
To:     Parav Pandit <parav@mellanox.com>,
        "kvm@vger.kernel.org" <kvm@vger.kernel.org>,
        "linux-kernel@vger.kernel.org" <linux-kernel@vger.kernel.org>,
        "alex.williamson@redhat.com" <alex.williamson@redhat.com>
References: <1553296835-37522-1-git-send-email-parav@mellanox.com>
 <1553296835-37522-6-git-send-email-parav@mellanox.com>
From:   Kirti Wankhede <kwankhede@nvidia.com>
Message-ID: <6f990e18-296c-cd33-df2b-c5c4bad7a740@nvidia.com>
Date:   Tue, 26 Mar 2019 00:48:21 +0530
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On 3/23/2019 4:50 AM, Parav Pandit wrote:
> Instead of masking return error to -EBUSY, return actual error
> returned by the driver.
> 
> Signed-off-by: Parav Pandit <parav@mellanox.com>
> ---
>  drivers/vfio/mdev/mdev_core.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/vfio/mdev/mdev_core.c b/drivers/vfio/mdev/mdev_core.c
> index 3d91f62..ab05464 100644
> --- a/drivers/vfio/mdev/mdev_core.c
> +++ b/drivers/vfio/mdev/mdev_core.c
> @@ -142,7 +142,7 @@ static int mdev_device_remove_ops(struct mdev_device *mdev, bool force_remove)
>  	 */
>  	ret = parent->ops->remove(mdev);
>  	if (ret && !force_remove)
> -		return -EBUSY;
> +		return ret;
>  
>  	sysfs_remove_groups(&mdev->dev.kobj, parent->ops->mdev_attr_groups);
>  	return 0;
> 

Intentionally returned -EBUSY here. If VMM or userspace application is
using this mdev device, vendor driver can return error. In that case
sysfs interface should see -EBUSY error indicating device is still active.

Thanks,
Kirti