Received-SPF: pass (google.com: domain of linux-kernel+bounces-31175-linux.lists.archive=gmail.com@vger.kernel.org designates 147.75.80.249 as permitted sender) client-ip=147.75.80.249;
Precedence: bulk
MIME-Version: 1.0
References: <20240119125753.152354-1-npache@redhat.com>
In-Reply-To: <20240119125753.152354-1-npache@redhat.com>
From: Nico Pache <npache@redhat.com>
Date: Fri, 19 Jan 2024 06:11:53 -0700
Message-ID: <CAA1CXcD55JLQfpW8OzzfHsyaVX5cJHO-y7v8miRyL1t3fnejqg@mail.gmail.com>
Subject: Re: [PATCH] selftests: mm: fix map_hugetlb failure on 64K page size systems
To: linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, 
	linux-mm@kvack.org
Cc: akpm@linux-foundation.org, shuah@kernel.org, donettom@linux.vnet.ibm.com
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable

NACK.

I accidentally sent an older version of this patch. Following up with V2.

On Fri, Jan 19, 2024 at 5:58=E2=80=AFAM Nico Pache <npache@redhat.com> wrot=
e:
>
> On systems with 64k page size and 512M huge page sizes, the allocation
> and test succeeds but errors out at the munmap. As the comment states,
> munmap will failure if its not HUGEPAGE aligned. This is due to the
> length of the mapping being 1/2 the size of the hugepage causing the
> munmap to not be hugepage aligned. Fix this by making the mapping length
> the full hugepage if the hugepage is larger than the length of the
> mapping.
>
> Signed-off-by: Nico Pache <npache@redhat.com>
> ---
>  tools/testing/selftests/mm/map_hugetlb.c | 6 ++++++
>  1 file changed, 6 insertions(+)
>
> diff --git a/tools/testing/selftests/mm/map_hugetlb.c b/tools/testing/sel=
ftests/mm/map_hugetlb.c
> index 193281560b61..dcb8095fcd45 100644
> --- a/tools/testing/selftests/mm/map_hugetlb.c
> +++ b/tools/testing/selftests/mm/map_hugetlb.c
> @@ -58,10 +58,16 @@ int main(int argc, char **argv)
>  {
>         void *addr;
>         int ret;
> +       size_t maplength;
>         size_t length =3D LENGTH;
>         int flags =3D FLAGS;
>         int shift =3D 0;
>
> +       maplength =3D default_huge_page_size();
> +       /* mmap with fail if the length is not page */
> +       if (maplength > length)
> +               length =3D maplength;
> +
>         if (argc > 1)
>                 length =3D atol(argv[1]) << 20;
>         if (argc > 2) {
> --
> 2.43.0
>