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charset="us-ascii" Content-ID: <9DD1DDC49E2F744CBC9BA871BF06DBB5@namprd10.prod.outlook.com> Content-Transfer-Encoding: quoted-printable Precedence: bulk X-Mailing-List: netdev@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-ExternalHop-MessageData-0: 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 X-OriginatorOrg: oracle.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-AuthSource: BN0PR10MB5128.namprd10.prod.outlook.com X-MS-Exchange-CrossTenant-Network-Message-Id: 69ef8fe9-8cfc-4eb5-5550-08db4d8b6beb X-MS-Exchange-CrossTenant-originalarrivaltime: 05 May 2023 17:09:00.9079 (UTC) X-MS-Exchange-CrossTenant-fromentityheader: Hosted X-MS-Exchange-CrossTenant-id: 4e2c6054-71cb-48f1-bd6c-3a9705aca71b X-MS-Exchange-CrossTenant-mailboxtype: HOSTED X-MS-Exchange-CrossTenant-userprincipalname: HkveW9D4Q0SuIV2LWB286Lb7gYEpGlGAU/mPHG3+HJrArLuOeZGvxVpj+EBitYSC6JBV/8GSebdjyaYM1Kat4g== X-MS-Exchange-Transport-CrossTenantHeadersStamped: SJ0PR10MB5408 X-Proofpoint-Virus-Version: vendor=baseguard engine=ICAP:2.0.254,Aquarius:18.0.942,Hydra:6.0.573,FMLib:17.11.170.22 definitions=2023-05-05_23,2023-05-05_01,2023-02-09_01 X-Proofpoint-Spam-Details: rule=notspam policy=default score=0 adultscore=0 phishscore=0 spamscore=0 mlxlogscore=999 bulkscore=0 suspectscore=0 mlxscore=0 malwarescore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.12.0-2303200000 definitions=main-2305050142 X-Proofpoint-ORIG-GUID: 1tkL2wSzf-SnkCI8H-Z4RwQnYrmk70q3 X-Proofpoint-GUID: 1tkL2wSzf-SnkCI8H-Z4RwQnYrmk70q3 X-Spam-Status: No, score=-2.8 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,RCVD_IN_DNSWL_LOW, RCVD_IN_MSPIKE_H2,SPF_HELO_NONE,SPF_NONE,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net > On May 5, 2023, at 12:59 PM, Stephen Hemminger wrote: >=20 > On Fri, 05 May 2023 11:42:17 -0400 > Chuck Lever wrote: >=20 >> From: Chuck Lever >>=20 >> A non-zero MAC address enables a network device to be assigned as >> the underlying device for a virtual RDMA device. Without a non- >> zero MAC address, cma_acquire_dev_by_src_ip() is unable to find the >> underlying egress device that corresponds to a source IP address, >> and rdma_resolve_address() fails. >>=20 >> Signed-off-by: Chuck Lever >> --- >> drivers/net/tun.c | 6 +++--- >> 1 file changed, 3 insertions(+), 3 deletions(-) >>=20 >> diff --git a/drivers/net/tun.c b/drivers/net/tun.c >> index d4d0a41a905a..da85abfcd254 100644 >> --- a/drivers/net/tun.c >> +++ b/drivers/net/tun.c >> @@ -1384,7 +1384,7 @@ static void tun_net_initialize(struct net_device *= dev) >>=20 >> /* Point-to-Point TUN Device */ >> dev->hard_header_len =3D 0; >> - dev->addr_len =3D 0; >> + dev->addr_len =3D ETH_ALEN; >> dev->mtu =3D 1500; >>=20 >> /* Zero header length */ >=20 > This is a bad idea. > TUN devices are L3 devices without any MAC address. > This patch will change the semantics and break users. I suspected this might be a problem, thanks for the quick feedback. > If you want an L2 address, you need to use TAP, not TUN device. We can't assume how the VPN is implemented. In our case, it's Tailscale, which creates a tun device. wireguard (in kernel) is the same. We would prefer a mechanism that can support tun. Having a MAC is the easiest way forward, but is not a hard requirement AFAICT. -- Chuck Lever