Re: [PATCH v3 12/12] vfio/pci: Report dev_id in VFIO_DEVICE_GET_PCI_HOT_RESET_INFO

Jason Gunthorpe
2023-04-18T12:59:32Z

On Tue, Apr 18, 2023 at 05:02:44AM +0000, Tian, Kevin wrote:

> Yes I chatted with Yi about it.
>
> If the calling device of the INFO ioctl is opened by group then behave
> as it does today.
>
> If the calling device is opened via cdev then use dev_id scheme as
> discussed above.
>
> in hot_reset ioctl the fd array only accepts group fd's.
>
> cdev can be reset only via null fd array.

Agree

> It remains a small open that null fd array could potentially work for
> group-opened device too if vfio-compat is used. In that case devices
> are in same iommufd ctx with valid dev_id even though they are opened
> via group. But probably it's not worthy blocking it?

IMHO not worth the complexity to block. Security is maintained if we
use an iommufd_ctx check.

Jason