Re: [PATCH] Revert "tmpfs: don't enable large folios if not supported"

[Baolin Wang <baolin.wang@linux.alibaba.com>]

On 5/12/26 6:01 AM, Andrew Morton wrote:
> On Mon, 11 May 2026 13:03:04 +0100 Lorenzo Stoakes <ljs@kernel.org> wrote:
> 
>> On Wed, May 06, 2026 at 04:58:20PM +0800, Baolin Wang wrote:
>>>
>>>
>>> On 5/5/26 6:47 PM, Lorenzo Stoakes wrote:
>>>> On Tue, May 05, 2026 at 11:46:11AM +0100, Lorenzo Stoakes wrote:
>>>>> Acked-by: Lorenzo Stoakes <ljs@kernel.org>
>>>>>
>>>>> As David asked, should we have a Fixes tag? What about cc: stable?
>>>
>>> Sure. But this fix tag depends on the commit 665575cff098b, so the fixes tag
>>> should be:
>>>
>>> Fixes: 5a90c155defa ("tmpfs: don't enable large folios if not supported")
>>> Depends-on: 665575cff098b ("filemap: move prefaulting out of hot write
>>> path").
>>
>> Oh is Depends-on a tag? Wasn't aware of it :>)
> 
> It is not.
> 
> hp2:/usr/src/25> grep -ri Depends-on Documentation | wc -l
> 0
> 
> But it is!
> 
> hp2:/usr/src/25> grep -ri Depends-on ../gitlog | wc -l
> 156
> 
> I actually removed it because a) various tools whine at me and b) we
> didn't cc:stable anyway.

Okay, I remember I've seen that tag :)

> 
> Please let's not add new metadata without having told others what that
> metadata means?
> 
> "Fixes:" should be sufficient.  I interpret Fixes: as "apply this to any
> kernel which contains <that>".  Is more needed?

My concern is that if someone backports this patch to an older kernel 
version without also backporting commit 665575cff098b, it would cause a 
performance regression.

Is there a good way to mark this kind of dependency on another patch? 
But I've already described this potential dependency in the commit 
message, so I'm fine with just adding the "Fixes:" tag.