23 Mar
2023
23 Mar
'23
2:23 p.m.
On Thu, Mar 23, 2023 at 07:21:42AM +0000, Tian, Kevin wrote:
From: Jason Gunthorpe jgg@nvidia.com Sent: Wednesday, March 22, 2023 3:15 AM
/*
* FIXME: Hack around missing a device-centric iommu api, onlyattach to
* the group once for the first device that is in the group.
* Only attach to the group once for the first device that is in the* group. All the other devices will follow this attachment. The user* should attach every device individually to as the per-devicereserved
"individually to the hwpt"
Done
I thought about whether holding igroup->lock is necessary here.
The caller should avoid racing attach/detach/replace on the same device.
I think even if the caller races we should be fine
The point of the lock scope was the capture these lines:
rc = iopt_table_add_domain(&hwpt->ioas->iopt, hwpt->domain); if (rc) goto out_detach; list_add_tail(&hwpt->hwpt_item, &hwpt->ioas->hwpt_list);
But based on the current arrangement none of them rely on the igroup mutex so it does seem we can narrow it
Thanks, Jason