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Date:   Tue, 11 Jul 2023 18:57:33 +0100
From:   Mark Brown <broonie@kernel.org>
To:     Hugh Dickins <hughd@google.com>
Cc:     Lorenzo Stoakes <lstoakes@gmail.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        Mike Kravetz <mike.kravetz@oracle.com>,
        Mike Rapoport <rppt@kernel.org>,
        "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>,
        Matthew Wilcox <willy@infradead.org>,
        David Hildenbrand <david@redhat.com>,
        Suren Baghdasaryan <surenb@google.com>,
        Qi Zheng <zhengqi.arch@bytedance.com>,
        Yang Shi <shy828301@gmail.com>,
        Mel Gorman <mgorman@techsingularity.net>,
        Peter Xu <peterx@redhat.com>,
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        Will Deacon <will@kernel.org>, Yu Zhao <yuzhao@google.com>,
        Alistair Popple <apopple@nvidia.com>,
        Ralph Campbell <rcampbell@nvidia.com>,
        Ira Weiny <ira.weiny@intel.com>,
        Steven Price <steven.price@arm.com>,
        SeongJae Park <sj@kernel.org>,
        Huang Ying <ying.huang@intel.com>,
        Naoya Horiguchi <naoya.horiguchi@nec.com>,
        Christophe Leroy <christophe.leroy@csgroup.eu>,
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Subject: Re: [PATCH v2 12/32] mm/vmalloc: vmalloc_to_page() use
 pte_offset_kernel()
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On Tue, Jul 11, 2023 at 09:13:18AM -0700, Hugh Dickins wrote:
> On Tue, 11 Jul 2023, Mark Brown wrote:
> > On Mon, Jul 10, 2023 at 09:34:42PM -0700, Hugh Dickins wrote:
> >=20
> > > I suppose I should ask you to try reverting this 0d1c81edc61e alone
> > > from 6.5-rc1: the consistency of your bisection implies that it will
> > > "fix" the issues, and it is a commit which we could drop.  It makes
> > > me a little nervous, applying userspace-pagetable validation to kernel
> > > pagetables, so I don't want to drop it; and it would really be cargo-
> > > culting to drop it without understanding.  But we could drop it.
> >=20
> > I did look at that, it doesn't revert cleanly by itself. ...
>=20
> Right, that ptep_get() wrapper on the next line came in on top.
> The patch to revert just 0d1c81edc61e is this:

Still investigating but I'm pretty convinced this is nothing to do with
your commit/series and is just common or garden memory corruption that
just happens to get tickled by your changes.  Sorry for the noise.

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