Re: [PATCH v2] mm: convert page type macros to enum

From: Stephen Brennan
Date: Thu Jun 06 2024 - 20:07:06 EST


David Hildenbrand <david@xxxxxxxxxx> writes:
> On 06.06.24 20:26, Stephen Brennan wrote:
>> Changing PG_slab from a page flag to a page type in commit 46df8e73a4a3
>> ("mm: free up PG_slab") in has the unintended consequence of removing
>> the PG_slab constant from kernel debuginfo. The commit does add the
>> value to the vmcoreinfo note, which allows debuggers to find the value
>> without hardcoding it. However it's most flexible to continue
>> representing the constant with an enum. To that end, convert the page
>> type fields into an enum. Debuggers will now be able to detect that
>> PG_slab's type has changed from enum pageflags to enum page_type.
>>
>> Fixes: 46df8e73a4a3 ("mm: free up PG_slab")
>>
>> Signed-off-by: Stephen Brennan <stephen.s.brennan@xxxxxxxxxx>
>> ---
>> v1 -> v2: include PAGE_TYPE_BASE and PAGE_MAPCOUNT_RESERVE
>
> This has a conflict with mm/mm-unstable.

Thank you, that's what I get for developing on master. I'll send v3
based on mm-unstable once it finishes compiling.

-Stephen