Re: [PATCH v2 11/20] vfio/common: Add device dirty page tracking start/stop

[Alex Williamson]

On Thu, 23 Feb 2023 15:30:28 -0400
Jason Gunthorpe <jgg@nvidia.com> wrote:

> On Thu, Feb 23, 2023 at 12:27:23PM -0700, Alex Williamson wrote:
> > So again, I think I'm just looking for a better comment that doesn't
> > add FUD to the reasoning behind switching to a single range,   
> 
> It isn't a single range, it is a single page of ranges, right?

Exceeding a single page of ranges is the inflection point at which we
switch to a single range.
 
> The comment should say
> 
> "Keep the implementation simple and use at most a PAGE_SIZE of ranges
> because the kernel is guaranteed to be able to parse that"

Something along those lines, yeah.  And bonus points for noting that
the kernel implementation is currently hard coded at this limit, so
there's no point in trying larger arrays as implied in the uAPI.
Thanks,

Alex