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From:   Song Liu <songliubraving@fb.com>
To:     William Kucharski <william.kucharski@oracle.com>
CC:     LKML <linux-kernel@vger.kernel.org>, Linux-MM <linux-mm@kvack.org>,
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Subject: Re: [PATCH uprobe, thp 3/4] uprobe: support huge page by only
 splitting the pmd
Thread-Topic: [PATCH uprobe, thp 3/4] uprobe: support huge page by only
 splitting the pmd
Thread-Index: AQHVFma7iu6PqkG6zkadRvREvp8axaaDg0iAgABpC4A=
Date:   Thu, 30 May 2019 17:24:42 +0000
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> On May 30, 2019, at 4:08 AM, William Kucharski <william.kucharski@oracle.=
com> wrote:
>=20
>=20
> Is there any reason to worry about supporting PUD-sized uprobe pages if
> CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is defined? I would prefer
> not to bake in the assumption that "huge" means PMD-sized and more than
> it already is.
>=20
> For example, if CONFIG_HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD is configured,
> mm_address_trans_huge() should either make the call to pud_trans_huge()
> if appropriate, or a VM_BUG_ON_PAGE should be added in case the routine
> is ever called with one.
>=20
> Otherwise it looks pretty reasonable to me.
>=20
>    -- Bill
>=20

I will try that in v2.=20

Thanks,
Song=