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Date:   Mon, 3 Jul 2023 18:29:36 -0300
From:   Jason Gunthorpe <jgg@ziepe.ca>
To:     Claudio Imbrenda <imbrenda@linux.ibm.com>
Cc:     Hugh Dickins <hughd@google.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Gerald Schaefer <gerald.schaefer@linux.ibm.com>,
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Subject: Re: [PATCH v2 07/12] s390: add pte_free_defer() for pgtables sharing
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On Mon, Jul 03, 2023 at 01:00:13PM +0200, Claudio Imbrenda wrote:
> On Fri, 30 Jun 2023 12:22:43 -0700 (PDT)
> Hugh Dickins <hughd@google.com> wrote:
> 
> [...]
> 
> > That's something I would have expected to be handled already via
> > mmu_notifiers, rather than buried inside the page table freeing.
> > 
> > If s390 is the only architecture to go that way, and could instead do
> > it via mmu_notifiers, then I think that will be more easily supported
> > in the long term.
> 
> I am very well aware of that, and in fact I've been working on
> exactly that for some time already. But it's a very complex minefield
> and therefore I'm proceeding *very* carefully. It will take quite some
> time before anything comes out.

Yes +1 on this please, creating your own arch cross connect with kvm
in the page table freers is really horrible..

Jason