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Date:   Tue, 11 Jul 2023 13:57:53 -0400
From:   "Liam R. Howlett" <Liam.Howlett@Oracle.com>
To:     Ryan Roberts <ryan.roberts@arm.com>
Cc:     linux-mm@kvack.org, linux-kernel@vger.kernel.org,
        Andrew Morton <akpm@linux-foundation.org>,
        maple-tree@lists.infradead.org
Subject: Re: [PATCH v4 18/49] mlock: Convert mlock to vma iterator
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* Ryan Roberts <ryan.roberts@arm.com> [230711 11:30]:
> On 11/07/2023 16:27, Liam R. Howlett wrote:
> > * Ryan Roberts <ryan.roberts@arm.com> [230711 10:09]:
> >> On 20/01/2023 16:26, Liam R. Howlett wrote:
> >>> From: "Liam R. Howlett" <Liam.Howlett@Oracle.com>
> >>>
> >>> Use the vma iterator so that the iterator can be invalidated or updated
> >>> to avoid each caller doing so.
> >>
> >> Hi,
> > 
> > 
> > Hello!
> > 
> >>
> >> I've bisected 2 mm selftest regressions back to this patch, so hoping someone can help debug and fix? The failures are reproducible on x86_64 and arm64.
> > 
> > Thanks!  That is a big help.  Where did you start your bisection?  I
> > assume 6.4?
> 
> Yes, I'm working to get all the mm selftests running (and ideally passing!) on
> arm64. I working on v6.4 and it was broken there. I went arbitrarily back to
> v5.10 and it was working there, so bisected between them.
> 

Annoyingly, this is similar to another bug I had fixed in another
iterator across VMAs.  It's the same pattern and I did go back to see if
I had broken other places but, obviously, I missed this one.

It's annoying enough that I'm trying to figure out a better way to do
this in general.. A contiguous iterator of sorts.  I will add this to my
maple tree work list [1].

[1] http://lists.infradead.org/pipermail/maple-tree/2023-July/002683.html

Thanks,
Liam