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charset="us-ascii" Content-ID: Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 X-OriginatorOrg: microsoft.com X-MS-Exchange-CrossTenant-Network-Message-Id: c0ee592c-4dd6-43bd-6fa6-08d603a5354f X-MS-Exchange-CrossTenant-originalarrivaltime: 16 Aug 2018 18:22:21.6407 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 72f988bf-86f1-41af-91ab-2d7cd011db47 X-MS-Exchange-Transport-CrossTenantHeadersStamped: DM5PR21MB0843 Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > d) What's the maximum number of nodes, ever? Perhaps we can always > > fit a nodemask_t onto the stack, dunno. >=20 > Right now, we define the maximum as NODES_SHIFT =3D 10, so: >=20 > 1 << 10 =3D 1024 Maximum nodes. >=20 > Since this makes only 128 bytes, I wonder if we can just go ahead and def= ine a nodemask_t > whithin the stack. > 128 bytes is not that much, is it? Yeah, sue stack here, 128b is tiny. This also will solve Andrew's point of = having an untested path when alloc fails, and simplify the patch overall. Thank you, Pavel=