Re: [PATCH] mm/rmap: fix incorrect pte restoration for lazyfree folios

[Lorenzo Stoakes <lorenzo.stoakes@oracle.com>]

On Tue, Feb 24, 2026 at 11:31:24AM +0000, Lorenzo Stoakes wrote:
> Thanks Dev.
>
> Andrew - why was commit 354dffd29575 ("mm: support batched unmap for lazyfree
> large folios during reclamation") merged?
>
> It had enormous amounts of review commentary at
> https://lore.kernel.org/all/146b4cb1-aa1e-4519-9e03-f98cfb1135d2@redhat.com/ and
> no tags, this should be a signal to wait for a respin _at least_, and really if
> late in cycle suggests it should wait a cycle.
>
> I've said going forward I'm going to check THP series for tags and if not
> present NAK if they hit mm-stable, I guess I'll extend that to rmap also.

Sorry I misread the original mail rushing through this is old... so this is less
pressing than I thought (for some reason I thought it was merged last cycle...!)
but it's a good example of how stuff can go unnoticed for a while.

In that case maybe a revert is a bit much and we just want the simplest possible
fix for backporting.

But is the proposed 'just assume wrprotect' sensible? David?

Thanks, Lorenzo