Re: [PATCH 09/10] virtio/s390: use DMA memory for ccw I/O and classic notifiers

Pierre Morel
2019-05-09T13:30:08Z

On 08/05/2019 16:46, Pierre Morel wrote:
> On 26/04/2019 20:32, Halil Pasic wrote:
>> Before virtio-ccw could get away with not using DMA API for the pieces of
>> memory it does ccw I/O with. With protected virtualization this has to
>> change, since the hypervisor needs to read and sometimes also write these
>> pieces of memory.
>>
>> The hypervisor is supposed to poke the classic notifiers, if these are
>> used, out of band with regards to ccw I/O. So these need to be allocated
>> as DMA memory (which is shared memory for protected virtualization
>> guests).
>>
>> Let us factor out everything from struct virtio_ccw_device that needs to
>> be DMA memory in a satellite that is allocated as such.
>>
...
>> +                       sizeof(indicators(vcdev)));
>
> should be sizeof(long) ?
>
> This is a recurrent error, but it is not an issue because the size of
> the indicators is unsigned long as the size of the pointer.
>
> Regards,
> Pierre
>

Here too, with the problem of the indicator size handled:
Reviewed-by: Pierre Morel<pmorel@linux.ibm.com>

--
Pierre Morel
Linux/KVM/QEMU in Böblingen - Germany