Re: [PATCH v3 8/8] virtio/s390: make airq summary indicators DMA

Cornelia Huck
2019-06-03T16:03:48Z

On Wed, 29 May 2019 14:26:57 +0200
Michael Mueller <mimu@linux.ibm.com> wrote:

> From: Halil Pasic <pasic@linux.ibm.com>
>
> Hypervisor needs to interact with the summary indicators, so these
> need to be DMA memory as well (at least for protected virtualization
> guests).
>
> Signed-off-by: Halil Pasic <pasic@linux.ibm.com>
> Signed-off-by: Michael Mueller <mimu@linux.ibm.com>
> ---
> drivers/s390/virtio/virtio_ccw.c | 26 +++++++++++++++++++-------
> 1 file changed, 19 insertions(+), 7 deletions(-)

(...)

> @@ -1501,6 +1508,11 @@ static int __init virtio_ccw_init(void)
> {
> /* parse no_auto string before we do anything further */
> no_auto_parse();
> +
> + summary_indicators = cio_dma_zalloc(MAX_AIRQ_AREAS);
> + if (!summary_indicators)
> + return -ENOMEM;
> +
> return ccw_driver_register(&virtio_ccw_driver);

Don't you need to free summary_indicators again if registering the
driver fails?

> }
> device_initcall(virtio_ccw_init);