Re: [PATCH v4 1/3] s390/vfio-ap: unpin pages on gisc registration failure

From: Christian Borntraeger <borntraeger@linux.ibm.com>
To: Tony Krowiak <akrowiak@linux.ibm.com>,
	linux-s390@vger.kernel.org, linux-kernel@vger.kernel.org,
	kvm@vger.kernel.org, Heiko Carstens <hca@linux.ibm.com>,
	Vasily Gorbik <gor@linux.ibm.com>,
	Alexander Gordeev <agordeev@linux.ibm.com>
Cc: jjherne@linux.ibm.com, pasic@linux.ibm.com,
	alex.williamson@redhat.com, kwankhede@nvidia.com,
	frankja@linux.ibm.com, imbrenda@linux.ibm.com, david@redhat.com,
	Matthew Rosato <mjrosato@linux.ibm.com>,
	stable@vger.kernel.org
Subject: Re: [PATCH v4 1/3] s390/vfio-ap: unpin pages on gisc registration failure
Date: Fri, 1 Dec 2023 10:56:45 +0100	[thread overview]
Message-ID: <d9fb5a2b-2250-f319-1207-5697bcf190d3@linux.ibm.com> (raw)
In-Reply-To: <20231129145404.263764-2-akrowiak@linux.ibm.com>

Am 29.11.23 um 15:53 schrieb Tony Krowiak:
> From: Anthony Krowiak <akrowiak@linux.ibm.com>
> 
> In the vfio_ap_irq_enable function, after the page containing the
> notification indicator byte (NIB) is pinned, the function attempts
> to register the guest ISC. If registration fails, the function sets the
> status response code and returns without unpinning the page containing
> the NIB. In order to avoid a memory leak, the NIB should be unpinned before
> returning from the vfio_ap_irq_enable function.
> 
> Co-developed-by: Janosch Frank <frankja@linux.ibm.com>
> Signed-off-by: Janosch Frank <frankja@linux.ibm.com>
> Signed-off-by: Anthony Krowiak <akrowiak@linux.ibm.com>
> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>
> Fixes: 783f0a3ccd79 ("s390/vfio-ap: add s390dbf logging to the vfio_ap_irq_enable function")
> Cc: <stable@vger.kernel.org>

Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>

should go via the s390 tree
Tony, please CC Heiko, Vasily and Alexander

> ---
>   drivers/s390/crypto/vfio_ap_ops.c | 1 +
>   1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 4db538a55192..9cb28978c186 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -457,6 +457,7 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
>   		VFIO_AP_DBF_WARN("%s: gisc registration failed: nisc=%d, isc=%d, apqn=%#04x\n",
>   				 __func__, nisc, isc, q->apqn);
>   
> +		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
>   		status.response_code = AP_RESPONSE_INVALID_GISA;
>   		return status;
>   	}