On 2023/1/9 22:14, Jason Gunthorpe wrote:
On Mon, Jan 09, 2023 at 07:47:03AM +0000, Tian, Kevin wrote:
From: Liu, Yi L <yi.l.liu@xxxxxxxxx>
Sent: Monday, December 19, 2022 4:47 PM
@@ -415,7 +416,7 @@ static int vfio_device_first_open(struct
vfio_device_file *df,
if (!try_module_get(device->dev->driver->owner))
return -ENODEV;
- if (iommufd)
+ if (iommufd && !IS_ERR(iommufd))
ret = vfio_iommufd_bind(device, iommufd, dev_id, pt_id);
else
ret = vfio_device_group_use_iommu(device);
can you elaborate how noiommu actually works in the cdev path?
I still need someone to test the noiommu iommufd patch with dpdk, I'll
post it in a minute
I remembered I had mentioned I found one guy to help. But he mentioned
to me he has got some trouble. I think it may be due to environment. Let
me check with him tomorrow about if any update.
For cdev conversion no-iommu should be triggered by passing in -1 for
the iommufd file descriptor to indicate there is no translation. Then
the module parameter and security checks should be done before
allowing the open to succeed with an identity translation in place.
There should be a check that there is no iommu driver controlling the
device as well..
yes. I used ERR_PTR(-EINVAL) as an indicator of noiommu in this patch.
I admit this logic is incorrect. Should be
if (iommufd) {
if (IS_ERR(iommufd))
ret = 0;
else
ret = vfio_iommufd_bind(device, iommufd, dev_id, pt_id);
} else {
ret = vfio_device_group_use_iommu(device);
}
--
Regards,
Yi Liu
