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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?vvT7O314QxU8B9y5gFI4HJgj6v2tnPoepBQbYgijTq2gOkEbvQNLaUquX3VV?= =?us-ascii?Q?MHMrLY4QWt/EJoDg2LfQkM38p/N+N7RDGKhpNnKmIM8hWHxVfnft9kBj0zXY?= =?us-ascii?Q?ONKX3Vt9coCATQQue47B5E4HH7RV/+sX4HQtjnja6JTIw1OBNZQSnG2uaTSZ?= =?us-ascii?Q?5lCjOH2HymE4c1VlDbFqMzlt4M3K+q+vRN3o/jpTb3UcO9GpQYH7+qjc0/jz?= =?us-ascii?Q?2iKAGzgC9EYNlyujXO2DipR1nN0owDwjx16kWVNhYYm9UsJYiHIvKdOmAU2m?= =?us-ascii?Q?r3wU9sJ0cv/7ivmf0IhmtfUuOrme26JcRrkIyGGtFgJjSJ07Ub8Ci9/Ete0O?= =?us-ascii?Q?iTRDCmfqyjRbMj05cki4OggOBDgsNshK4cA65xK/8woWUSwnNY0ExRUmE/+I?= =?us-ascii?Q?M4Dbj4xq0W0jmp7LFD+H2FKOXhOEzousI9dv4l0vdftmpTnQpwYUDlka+kmo?= =?us-ascii?Q?9n+nWA2IYQL1wl6iJSRI8ci8cOmVCA2VGLcqqp1ZtkTiJh+DKcKyfarm4h5n?= =?us-ascii?Q?6f3PmEyPHuFpB8rq29lO2Y+mecl8bwfcKq/mzhpJgOXNm91fOVF1/f2GGR28?= =?us-ascii?Q?jLQIeZ5Uj2YnYxexAz8g2/Hr5UvceVEoJrrejsksOfOxcb4vXGAWvEVB9NWW?= =?us-ascii?Q?VbRRpsI4eN/9bee+fsvehoWP1CVvlWuZoSIIitKxBd8L8gZ9ONwv+dCKZmrW?= =?us-ascii?Q?r5oK0JifWlmhXd8+hdF2QJ7XwmpE94GAuFE/CdE5qasLt/Q8sV1eX+dekn+4?= =?us-ascii?Q?hiRL4N1B8v9fx69iUEvkrLYxDuG6+zLNFBviefky1hS0wM0kxv+rVR//2Ero?= =?us-ascii?Q?YnvwcKu8TijjDCZB3mWPXKMRieaK62A7eNc1E76l1DLhX5Ecn9r3qq0iDawZ?= =?us-ascii?Q?IRg5ozl4/HJqrFO3gaSSNqZUDfMG9p49/kU30sYFwG8s7D6gFc1SYKKeZgBH?= =?us-ascii?Q?lqlQjigV7AB+5LSDj/1lenCKvTu2s6BDrI4+QDWb0GDsld/yMRuWiKKhdiPY?= =?us-ascii?Q?KZsmm51pdimK3D7tUXqfsg/EJtHWmViqE4/peEaciYo7yxR0EoNyfHAFHb3Y?= =?us-ascii?Q?3BdmmPo+Mckczr2YcOqVFYMJbLIMHvp7e9uykCTSJeaz/cvOdgrTNoZoCkJl?= =?us-ascii?Q?3bY/2VwSsOQVs/o66CG9GnA0zQRIVWsEsYqtWU4euuxe7+cM60yaFidQhj7G?= =?us-ascii?Q?Woj2ZjY5bmFe3M4b3mHRdZMU6sgW5EYVzHMry+OPSuJvViQJ1CYUJ4I4R9Jx?= =?us-ascii?Q?WP1VCwFf1CYJawU2E9F6IJB+gm0dbferOIaVwCNg0mHWnvRAl4xNyOiHDljr?= =?us-ascii?Q?xRI2H/7ui3Nw3N7jnDV5BdMvF2Je6QJa7hH68niO8xRCOvw8dxmyzPkYYTMJ?= =?us-ascii?Q?4EX/E2PeTCxcecrzrthqhNZAZpBRGr9ce8eM7NhwCvd76RNGc+YjY7HcfM7j?= =?us-ascii?Q?VLX2uaZbjyDld0VraOVmRoMhXdi9AEHZdcmGA3Nyzx6P6O62qsF0q3hiiOcm?= =?us-ascii?Q?7BrcMPmf2H7K6K/vrtzmSt1xboKweHbgy3JNKrNVbmaiLeqyiooBg9tEzD2I?= =?us-ascii?Q?UbQIznCX4Q946e0/DXXRKF6azygP2pptJ/H5P3O5I90j0q3BwBJcZZUPTisW?= =?us-ascii?Q?1ozATXEnF5WoNV79dD/q9B/pyG4WUn8cmDJ9XBnFpcQ311evYrpGow+elyH4?= =?us-ascii?Q?petYhg=3D=3D?= X-OriginatorOrg: nxp.com X-MS-Exchange-CrossTenant-Network-Message-Id: acca7561-8365-4e2f-15cb-08de36fdebd0 X-MS-Exchange-CrossTenant-AuthSource: AM9PR04MB8585.eurprd04.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 09 Dec 2025 08:35:35.6149 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 686ea1d3-bc2b-4c6f-a92c-d99c5c301635 X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: H7lu74f7wUEBM14Fp5CEHFZCbhRD5mj4iza0QuVEnVjvgUFqAzXULw4bf4Eql2c/nxft8SwiNj/ziXGN0u6EWw== X-MS-Exchange-Transport-CrossTenantHeadersStamped: GVXPR04MB10071 On Fri, Dec 05, 2025 at 06:53:07PM +0800, Wei Fang wrote: > In the current implementation, the enetc_xdp_xmit() always transmits > redirected XDP frames even if the link is down, but the frames cannot > be transmitted from TX BD rings when the link is down, so the frames > are still kept in the TX BD rings. If the XDP program is uninstalled, > users will see the following warning logs. > > fsl_enetc 0000:00:00.0 eno0: timeout for tx ring #6 clear > > More worse, the TX BD ring cannot work properly anymore, because the > HW PIR and CIR are not the same after the re-initialization of the TX > BD ring. I understand and I don't disagree that the TX BD ring doesn't work anymore if we disable it while it has pending frames (the TB0MR[EN] documentation says that this is unsafe too), but: - I don't understand why the hardware PIR and CIR are not the same after the TX ring reinitialization - I don't understand how the effect and the claimed cause are connected Could you please give more details what you mean here? > And I see no reasons to transmit the redirected XDP frames > when the link is down, so add a link status check to quickly fix this > issue. However, this solution does not completely solve the problem, > for example, if the link is broken during transmission and the TX BD > ring still has unsent frames. I think this requires another patch to > address this situation, but it will not conflict with the current > solution and can coexist. > > Fixes: 9d2b68cc108d ("net: enetc: add support for XDP_REDIRECT") > Signed-off-by: Wei Fang > --- > drivers/net/ethernet/freescale/enetc/enetc.c | 3 ++- > 1 file changed, 2 insertions(+), 1 deletion(-) > > diff --git a/drivers/net/ethernet/freescale/enetc/enetc.c b/drivers/net/ethernet/freescale/enetc/enetc.c > index 0535e92404e3..f410c245ea91 100644 > --- a/drivers/net/ethernet/freescale/enetc/enetc.c > +++ b/drivers/net/ethernet/freescale/enetc/enetc.c > @@ -1778,7 +1778,8 @@ int enetc_xdp_xmit(struct net_device *ndev, int num_frames, > int xdp_tx_bd_cnt, i, k; > int xdp_tx_frm_cnt = 0; > > - if (unlikely(test_bit(ENETC_TX_DOWN, &priv->flags))) > + if (unlikely(test_bit(ENETC_TX_DOWN, &priv->flags) || > + !netif_carrier_ok(ndev))) > return -ENETDOWN; > > enetc_lock_mdio(); > -- > 2.34.1 >