Re: [PATCH v4 3/3] s390/vfio-ap: improve reaction to response code 07 from PQAP(AQIC) command

[Christian Borntraeger <borntraeger@linux.ibm.com>]

Am 29.11.23 um 15:54 schrieb Tony Krowiak:
> Let's improve the vfio_ap driver's reaction to reception of response code
> 07 from the PQAP(AQIC) command when enabling interrupts on behalf of a
> guest:
> 
> * Unregister the guest's ISC before the pages containing the notification
>    indicator bytes are unpinned.
> 
> * Capture the return code from the kvm_s390_gisc_unregister function and
>    log a DBF warning if it fails.
> 
> Suggested-by: Matthew Rosato <mjrosato@linux.ibm.com>
> Signed-off-by: Tony Krowiak <akrowiak@linux.ibm.com>
> Reviewed-by: Matthew Rosato <mjrosato@linux.ibm.com>

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

should go via the s390 tree

> ---
>   drivers/s390/crypto/vfio_ap_ops.c | 5 ++++-
>   1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/s390/crypto/vfio_ap_ops.c b/drivers/s390/crypto/vfio_ap_ops.c
> index 25d7ce2094f8..4e80c211ba47 100644
> --- a/drivers/s390/crypto/vfio_ap_ops.c
> +++ b/drivers/s390/crypto/vfio_ap_ops.c
> @@ -476,8 +476,11 @@ static struct ap_queue_status vfio_ap_irq_enable(struct vfio_ap_queue *q,
>   		break;
>   	case AP_RESPONSE_OTHERWISE_CHANGED:
>   		/* We could not modify IRQ settings: clear new configuration */
> +		ret = kvm_s390_gisc_unregister(kvm, isc);
> +		if (ret)
> +			VFIO_AP_DBF_WARN("%s: kvm_s390_gisc_unregister: rc=%d isc=%d, apqn=%#04x\n",
> +					 __func__, ret, isc, q->apqn);
>   		vfio_unpin_pages(&q->matrix_mdev->vdev, nib, 1);
> -		kvm_s390_gisc_unregister(kvm, isc);
>   		break;
>   	default:
>   		pr_warn("%s: apqn %04x: response: %02x\n", __func__, q->apqn,