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Date: Sun, 21 Jul 2024 16:52:25 -0700
From: Andrew Morton <akpm@linux-foundation.org>
To: Linus Torvalds <torvalds@linux-foundation.org>
Cc: linux-mm@kvack.org, mm-commits@vger.kernel.org,
 linux-kernel@vger.kernel.org
Subject: Re: [GIT PULL] MM updates for 6.11-rc1
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On Sun, 21 Jul 2024 16:19:42 -0700 Linus Torvalds <torvalds@linux-foundation.org> wrote:

> On Sun, 21 Jul 2024 at 14:54, Andrew Morton <akpm@linux-foundation.org> wrote:
> >
> > - 875fa64577da ("mm/hugetlb_vmemmap: fix race with speculative PFN
> >   walkers") is known to cause a performance regression
> >   (https://lore.kernel.org/all/3acefad9-96e5-4681-8014-827d6be71c7a@linux.ibm.com/T/#mfa809800a7862fb5bdf834c6f71a3a5113eb83ff).
> >   Yu has a fix which I'll send along later via the hotfixes branch.
> 
> That commit "875fa64577da" does not exist. I think you are talking
> about commit bd225530a4c7, which is in 6.10 and came in from your last
> hotfixes pull.
> 
> I'm assuming 875fa64577da was some commit ID it had before getting
> rebased or something?
> 
> I'm also a bit confused about why you mention this, since neither the
> cause _nor_ the fix are in this pull request and you have the wrong
> commit ID.
> 

Yes, right, sorry.  "mm/hugetlb_vmemmap: fix race with speculative PFN
walkers" was promoted into mm-hotfixes after I make this note.

Anyway.  We broke a thing and it's being fixed.