RE: [PATCH v7 9/9] iommu/vt-d: Add iotlb flush for nested domain

[Tian, Kevin]

> From: Liu, Yi L <yi.l.liu@xxxxxxxxx>
> Sent: Tuesday, December 26, 2023 12:52 PM
> >> +
> >> +		if (!IS_ALIGNED(inv_entry.addr, VTD_PAGE_SIZE) ||
> >> +		    ((inv_entry.npages == U64_MAX) && inv_entry.addr)) {
> >> +			ret = -EINVAL;
> >> +			break;
> >> +		}
> >> +
> >
> > why is [non-zero-addr, U64_MAX] an error? Is it explicitly stated to
> > be not supported by underlying helpers?
> 
> no such limitation by underlying helpers. But in such case, the
> addr+npages*PAGE_SIZE would exceed U64_MAX, this seems a bit
> strange. But I'm fine to relax the check since the underlying helper
> only checks npages when determining paid-selective or not.
> 

I overlooked npages as end. let's keep the check.