Re: [PATCH v4 3/5] iommu/uapi: Use named union for user data

Lu Baolu
2020-07-08T02:23:21Z

Hi Jacob,

On 7/8/20 7:43 AM, Jacob Pan wrote:
> IOMMU UAPI data size is filled by the user space which must be validated
> by ther kernel. To ensure backward compatibility, user data can only be
> extended by either re-purpose padding bytes or extend the variable sized
> union at the end. No size change is allowed before the union. Therefore,
> the minimum size is the offset of the union.
>
> To use offsetof() on the union, we must make it named.
>
> Link:https://lkml.org/lkml/2020/6/11/834

Please use lore.kernel.org links.

Best regards,
baolu