Received-SPF: pass (google.com: domain of linux-kernel+bounces-211211-linux.lists.archive=gmail.com@vger.kernel.org designates 139.178.88.99 as permitted sender) client-ip=139.178.88.99;
Content-Type: text/plain;
	charset=us-ascii
Precedence: bulk
Mime-Version: 1.0 (Mac OS X Mail 16.0 \(3774.600.62\))
Subject: Re: [PATCH] mm/hugetlb: Guard dequeue_hugetlb_folio_nodemask against
 NUMA_NO_NODE uses
From: Muchun Song <muchun.song@linux.dev>
In-Reply-To: <20240612082936.10867-1-osalvador@suse.de>
Date: Wed, 12 Jun 2024 16:53:34 +0800
Cc: Andrew Morton <akpm@linux-foundation.org>,
 LKML <linux-kernel@vger.kernel.org>,
 Linux-MM <linux-mm@kvack.org>,
 Vivek Kasireddy <vivek.kasireddy@intel.com>,
 syzbot+569ed13f4054f271087b@syzkaller.appspotmail.com
Content-Transfer-Encoding: quoted-printable
Message-Id: <5237BBD3-818B-4E06-A56A-80BE705EB024@linux.dev>
References: <20240612082936.10867-1-osalvador@suse.de>
To: Oscar Salvador <osalvador@suse.de>


> On Jun 12, 2024, at 16:29, Oscar Salvador <osalvador@suse.de> wrote:
>=20
> dequeue_hugetlb_folio_nodemask() expects a preferred node where to get =
the
> hugetlb page from.
> It does not expect, though, users to pass NUMA_NO_NODE, otherwise we =
will
> get trash when trying to get the zonelist from that node.
> All current users are careful enough to not pass NUMA_NO_NODE, but
> it opens the door for new users to get this wrong since it is not
> documented [0].
> Guard against this by getting the local nid if NUMA_NO_NODE was =
passed.
>=20
> [0] =
https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/
>=20
> Closes: =
https://lore.kernel.org/linux-mm/0000000000004f12bb061a9acf07@google.com/
> Reported-and-tested-by: =
syzbot+569ed13f4054f271087b@syzkaller.appspotmail.com
> Signed-off-by: Oscar Salvador <osalvador@suse.de>

Reviewed-by: Muchun Song <muchun.song@linux.dev>

Thanks.=