Re: [PATCH v6 01/11] iommu: Add dma ownership management interfaces

Lu Baolu
2022-02-24T05:30:52Z

On 2/24/22 1:16 PM, Lu Baolu wrote:
> Hi Robin and Jason,
>
> On 2/24/22 2:02 AM, Jason Gunthorpe wrote:
>> On Wed, Feb 23, 2022 at 06:00:06PM +0000, Robin Murphy wrote:
>>
>>> ...and equivalently just set owner_cnt directly to 0 here. I don't see a
>>> realistic use-case for any driver to claim the same group more than
>>> once,
>>> and allowing it in the API just feels like opening up various potential
>>> corners for things to get out of sync.
>> I am Ok if we toss it out to get this merged, as there is no in-kernel
>> user right now.
>
> So we don't need the owner pointer in the API anymore, right?

Oh, NO.

The owner token represents that the group has been claimed for user
space access. And the default domain auto-attach policy will be changed
accordingly.

So we still need this. Sorry for the noise.

Best regards,
baolu