Re: [PATCH mm-unstable v4 5/5] mm/khugepaged: unify khugepaged and madv_collapse with collapse_single_pmd()

[Lorenzo Stoakes (Oracle)]

On Wed, Apr 01, 2026 at 01:31:45PM -0700, Andrew Morton wrote:
> On Wed, 1 Apr 2026 09:14:35 +0100 "Lorenzo Stoakes (Oracle)" <ljs@xxxxxxxxxx> wrote:
>
> > From: "Lorenzo Stoakes (Oracle)" <ljs@xxxxxxxxxx>
> > Date: Tue, 31 Mar 2026 13:11:18 +0100
> > Subject: [PATCH] mm/khugepaged: fix issue with tracking lock
> >
> > We are incorrectly treating lock_dropped to track both whether the lock is
> > currently held and whether or not the lock was ever dropped.
> >
> > Update this change to account for this.
> >
> > Signed-off-by: Lorenzo Stoakes (Oracle) <ljs@xxxxxxxxxx>
>
> Not sure if I should add this?
>
> Should it have
>
> Fixes: 330f3758a3bc ("mm/khugepaged: unify khugepaged and madv_collapse
> with collapse_single_pmd()")?

(Sorry only just noticed this)

I mean we do need this patch, if you plan to do this as a fix follow up then
should have a fixed tag, but I do worry about bisection hazard by leaving this
as-is.

We definitely either need this patch folded in or as a fix that gets sent
alongside the change.

Thanks, Lorenzo