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X-MS-Exchange-AntiSpam-MessageData-ChunkCount: 1 X-MS-Exchange-AntiSpam-MessageData-0: =?us-ascii?Q?K727VGdsSiBw3Rlkc/0D/PHm43GmYuCnMRNd7hyZQn+E5HHH0hHYj5JN1k4q?= =?us-ascii?Q?UmqrKGuK4xN+0yZ8y6s+62YZvw7xK4ly1AxO/OB+hvczH+HF9sQptYwIuuft?= =?us-ascii?Q?3fFWNR3JK7+l/MX0aYSeernZv4FTPkKFitmdT29RFkKtB8RxRacDwWU0B6a5?= =?us-ascii?Q?bo3kmTtKqGBFh93ZbqqmBWlXh4A5NyN6FqUDDuyN//XJmYEDiE91G3UH4Uu5?= =?us-ascii?Q?GdyR+sZpNytLcmIy7qMKdXJwz20bjNINbAUqmZNe6AIv4673JzKZwYeUhz5x?= =?us-ascii?Q?H4zD2TdBFR+RkGUHpo+aWAK6T5lENtGZoxRphMJa1VbTXyS9PwMjS8HyUJ9w?= =?us-ascii?Q?flY6t5hXjZNVUY0s9Egmiy5VR8fjzVVJl7Y5Vg1UWLRj8noiALlC20VQgOAd?= =?us-ascii?Q?bRZr+396V7b9y1qVDOTxH0heSbHZEedEOZHLaFxm5pek1WDyiVdqMWfiu8OH?= =?us-ascii?Q?p+wQPhK72IRg5VE+hz5iDhSM0k4RiykhDSR1HQB3ITcoxhHJGZ2+DTi+wX6D?= =?us-ascii?Q?aEsT1dKyMoUXksnhBhpLyt3xAWVDM/8vewwzEwOa2CmOkbnjkXD8jl+BLH8/?= =?us-ascii?Q?XSK66SmOpPBHuEx6JxdoeHbp0bDLG45FtFx42V8Feds7ibFE+d6SR7flyLPz?= =?us-ascii?Q?BVWm7RHRVx//ew4h4xprrU1R534gEeanMNW9qra8cEVFe0vPSW1PUC59+RHF?= =?us-ascii?Q?yV2gStdzt2cZ+I6Uh40xV9qBrVcy2OxlDAWcKjUb6sDhOv8E92Dti5ZCOVaf?= =?us-ascii?Q?AD6hQ/hcJ+3KW4sTIB+xskPabbIUZkXLt8HvmIa0y4zlzqFT4I8S6f5Lg9LI?= =?us-ascii?Q?IaVlMF4pA2AX0z/SEi7H2+ulPnAseicH9rI07jRXlLf9+Kdxb1h/PAq3pAVE?= =?us-ascii?Q?NWjuS4/gnzetSz7PuByNaPLRdgRJP1FdrLnSGa0wV/ltEZLAgJL2bTSHMShe?= =?us-ascii?Q?SnajF9rTkhOENUCO+xzehv41+nSIAdyIKKmUEMiVBw7/KORENUy3AdinGiaX?= =?us-ascii?Q?fPR4X6ynVkcdhTEVsrilmnrcRyCgVVBJKj8kMDbPTfQKXv+VhjqzNM+jMRJd?= =?us-ascii?Q?zKyFe9jOXjAsqz/rkkQreA9jaNzdXPXQYJ20TTw6ocIjc30Qvbt/9ZEwj2ST?= =?us-ascii?Q?/eGtGaRs97p6OOyVxdPeYmhLh26v/7Q9jbnrSwxw1dlXhr7hEWMcNPMu9kA9?= =?us-ascii?Q?lDsPd9H0YxExgAqXzTGyn1xVdY0oQk08cvQbCrQTbliJMK7I2ZPhnIMfT6BJ?= =?us-ascii?Q?il0q6+j2XPu/pFPvWTKwAN8GLThQ+HtQXGpT/3q7kRLuqTqNopfFd6RHfZS0?= =?us-ascii?Q?iA5ppK62wl5G8oUXX7e5Zt8z0G6MUQGGsWriIqjIdfjEMSFeNi5CUTY10hyM?= =?us-ascii?Q?MLd4Oap+ZDwq5twWv4WecSJQLYYHAG0Ah45l99MixuxlLEKYaxHs+owuUor4?= =?us-ascii?Q?bO5zNTAc/UFh6lqp6NUE7LSKjP5SWLHs8nwVREWDCXUMbdOYZeYbHSVqYP7Z?= =?us-ascii?Q?8CiOMCXX2mQU5TQkqTRCc9BEnGByLpacyihLX18yLBKOFO0phcSXQnjzSz6L?= =?us-ascii?Q?xYGpEFGU+/FGH9Bxj6wI9NXiYV/gM9OxkYWx3/ZqT/aJUup03PXU3g5wYPNp?= =?us-ascii?Q?ExbWxedCvMzouCGkLrMr6l0xT4ZBz1k0biHXOLkkXnpV6B/WGBq/DzXoH1OA?= =?us-ascii?Q?wDvpUc3FXs2RWfKAqcsq5DTeWypz7uKnVmmK+y0xZvBxucUJOuc/P25HR0iA?= =?us-ascii?Q?hzTDJ80U/A=3D=3D?= X-OriginatorOrg: Nvidia.com X-MS-Exchange-CrossTenant-Network-Message-Id: 519f0141-cb8e-4879-7bd7-08def3980921 X-MS-Exchange-CrossTenant-AuthSource: SA3PR12MB7901.namprd12.prod.outlook.com X-MS-Exchange-CrossTenant-AuthAs: Internal X-MS-Exchange-CrossTenant-OriginalArrivalTime: 06 Aug 2026 08:52:24.8059 (UTC) X-MS-Exchange-CrossTenant-FromEntityHeader: Hosted X-MS-Exchange-CrossTenant-Id: 43083d15-7273-40c1-b7db-39efd9ccc17a X-MS-Exchange-CrossTenant-MailboxType: HOSTED X-MS-Exchange-CrossTenant-UserPrincipalName: QzYy6LDLS8O0xXW64tFvsiXzqvZfn2DbxOxyv36XB/WZnB+dCr+0COvCvEVMorVSqnk6isIHczmvvAN3y4Tr1Q== X-MS-Exchange-Transport-CrossTenantHeadersStamped: LV1PR12MB999281 On Wed, Aug 05, 2026 at 05:29:02PM -0700, Jakub Kicinski wrote: > On Wed, 5 Aug 2026 12:07:21 +0300 Ido Schimmel wrote: > > __gre6_xmit() and ip6erspan_tunnel_xmit() already call skb_cow_head() > > before calling ip6_tnl_xmit(). > > Probably just me but can't they all be buggy? > PKTGEN likes to send shared skbs around in funny ways. > Can we get a good explanation in the commit msg or maybe let's > keep the check? ip6_tnl_xmit() is accessible via two Ethernet devices (pktgen doesn't support other types) and they both clear IFF_TX_SKB_SHARING, so if pktgen sends them shared skbs, I would say that it's a pktgen bug and not a reason to block this patch. Note that pktgen is not available to unprivileged users, so it's a less severe bug. The patch also makes ip6_tnl_xmit() consistent with its IPv4 counterpart (ip_tunnel_xmit()) which is already using skb_cow_head(). Zhiling, please add a note in the commit message that ip6gretap and ip6erspan do not expect to be handed shared skbs given that they clear IFF_TX_SKB_SHARING.