Re: [PATCH 1/2] fs/proc/task_mmu: add guard region bit to pagemap

[David Hildenbrand <david@redhat.com>]

>> My thinking was, that if you have a large VMA, with ordinary pagemap you
>> have to copy 8byte per entry (and have room for that somewhere in user
>> space). In theory, with the scanning feature, you can leave that ...
>> scanning to the kernel and don't have to do any copying/allocate space for
>> it in user space etc.
> 
> That makes perfect sense!
> 
> I think this one will go a little lower on priorities + I'll come back to it but
> I"ll put it on the one reliable todo list I have, the whiteboard in my home
> office :) everything on that list at least eventually gets looked at, majority
> get done.

Sounds good. I'm sure Android folks will speak up in case they require 
more efficient scanning.

> 
>>
>> --
>> Cheers,
>>
>> David / dhildenb
>>
> 
> Great minds think alike though ;) as soon as I saw this I did think about
> extending it, but seems I mistakenly dismissed for uffd reasons.
We should probably look into cleaning up + improving the documentation 
around the pagemap scan feature at some point. Well, something for 
another day :)

-- 
Cheers,

David / dhildenb