# Re: \[PATCH v1 05/11\] mm/sparse-vmemmap: add a pgmap argument to section activation

- From: Joao Martins \<hidden\>
- Date: 2021-05-05 22:38:04 
- List: linux-mm
- Page: https://ratatoskr.run/linux-mm/2021/05/6507976
- Thread: https://ratatoskr.run/linux-mm/2021/03/6507171/t.md

```text


On 5/5/21 11:34 PM, Dan Williams wrote:
> On Thu, Mar 25, 2021 at 4:10 PM Joao Martins [ref] wrote:
>>
>> @altmap is stored in a dev_pagemap, but it will be repurposed for
>> hotplug memory for storing the memmap in the hotplugged memory[*] and
>> reusing the altmap infrastructure to that end. This is to say that
>> altmap can't be replaced with a @pgmap as it is going to cover more than
>> dev_pagemap backend altmaps.
> 
> I was going to say, just pass the pgmap and lookup the altmap from
> pgmap, but Oscar added a use case for altmap independent of pgmap. So
> you might refresh this commit message to clarify why passing pgmap by
> itself is not sufficient.
> 
Isn't that what I am doing above with that exact paragraph? I even
reference his series at the end of commit description :) in [*]

> Other than that, looks good.
> 
/me nods

```