RE: [RFC 01/20] iommu/iommufd: Add /dev/iommu core

Tian, Kevin
2021-09-22T01:51:13Z

> From: Jason Gunthorpe <jgg@nvidia.com>
> Sent: Tuesday, September 21, 2021 11:42 PM
>
> - Delete the iommufd_ctx->lock. Use RCU to protect load, erase/alloc does
> not need locking (order it properly too, it is in the wrong order), and
> don't check for duplicate devices or dev_cookie duplication, that
> is user error and is harmless to the kernel.
>

I'm confused here. yes it's user error, but we check so many user errors
and then return -EINVAL, -EBUSY, etc. Why is this one special?