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Subject: Re: [PATCH 0/1] selftest/mm/hugetlb: SIGBUS on stolen page
From: Rik van Riel <riel@surriel.com>
To: Andrew Morton <akpm@linux-foundation.org>, Breno Leitao
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Date: Fri, 05 Jan 2024 14:00:58 -0500
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On Fri, 2024-01-05 at 08:42 -0800, Andrew Morton wrote:
> On Fri,=C2=A0 5 Jan 2024 07:54:18 -0800 Breno Leitao <leitao@debian.org>
> wrote:
>=20
> > This test case triggers a race between madvise(MADV_DONTNEED) and
> > mmap() in a single huge page, which got stolen (while reserved).
> >=20
> > Once the only page is stolen, the memory previously mmaped (and
> > madvise(MADV_DONTNEED) got a SIGBUS when accessed.
> >=20
> > I am not adding this test to the un_vmtests.sh scripts, since this
> > test
> > fails at upstream.
>=20
> Oh.=C2=A0 Is a fix for this in the pipeline?=C2=A0 If so, I assume that o=
nce
> the
> fix is merged, we enable this test in run_vmtests?
>=20
I've got some ideas on how to fix it, and hope to get
a fix to you and Mike by next week.

I'll ask Mike if I run into any unexpected complications.

--=20
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