On Wed, Mar 22, 2023 at 01:33:09PM +0000, Liu, Yi L wrote: > Thanks. So this new _INFO only reports a limited scope instead of > the full list of affected devices. Also, it is not static scope since device > may be opened just after the _INFO returns. Yes, it would be simplest for qemu to do the query after it gains a new dev_id and then it can add the new dev_id with the correct reset group. > > I'd probably use similar logic as the reset path, if one of reset > > group devices is open and on a different iommufd_ctx then fail the > > IOCTL with EPERM. > > Say there are three devices in the dev_set. When the first device is > opened by the current qemu, this new _INFO would return one dev_id > to user. When the second device is opened, this new _INFO will return > two dev_ids to user. Yes > If the third device is opened by another qemu, then > the new _INFO would fail since the former two devices were opened and > have different iommufd_ctx with the third device. Yes qemu should refuse to use the device at this moment. Jason
