Re: BUG: selftest/net/tun: Hang in unregister_netdevice

On 14. 03. 2023. 17:02, Eric Dumazet wrote:

On Tue, Mar 14, 2023 at 9:01 AM Mirsad Todorovac mirsad.todorovac@alu.unizg.hr wrote:

...

After a while, kernel message start looping:

kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3

Message from syslogd@pc-mtodorov at Mar 14 16:57:15 ... kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3

Message from syslogd@pc-mtodorov at Mar 14 16:57:24 ... kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3

Message from syslogd@pc-mtodorov at Mar 14 16:57:26 ... kernel:unregister_netdevice: waiting for tap0 to become free. Usage count = 3

This hangs processes until very late stage of shutdown.

I can confirm that CONFIG_DEBUG_{KOBJECT,KOBJECT_RELEASE}=y were the only changes to .config in between builds.

Best regards, Mirsad

Try adding in your config

CONFIG_NET_DEV_REFCNT_TRACKER=y CONFIG_NET_NS_REFCNT_TRACKER=y

Thanks.

Not at all.

According to the info here: https://cateee.net/lkddb/web-lkddb/NET_DEV_REFCNT_TRACKER.html no kerenel param was needed.

I have got the same hang, and additional debug information appears to be this (in /var/log/messages):

Mar 14 20:58:20 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:20 pc-mtodorov kernel: leaked reference. Mar 14 20:58:20 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:20 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:20 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:20 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:20 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:20 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:20 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:20 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:20 pc-mtodorov kernel: leaked reference. Mar 14 20:58:20 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:20 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:20 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:20 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:20 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:20 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:20 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:20 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:20 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:20 pc-mtodorov kernel: leaked reference. Mar 14 20:58:20 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:20 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:20 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:20 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:20 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:20 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:20 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:20 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:20 pc-mtodorov kernel: leaked reference. Mar 14 20:58:20 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:20 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:20 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:20 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:20 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:20 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:20 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:20 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:30 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:30 pc-mtodorov kernel: leaked reference. Mar 14 20:58:30 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:30 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:30 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:30 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:30 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:30 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:30 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:30 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:30 pc-mtodorov kernel: leaked reference. Mar 14 20:58:30 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:30 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:30 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:30 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:30 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:30 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:30 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:30 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:30 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:30 pc-mtodorov kernel: leaked reference. Mar 14 20:58:30 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:30 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:30 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:30 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:30 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:30 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:30 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:30 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:30 pc-mtodorov kernel: leaked reference. Mar 14 20:58:30 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:30 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:30 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:30 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:30 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:30 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:30 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:30 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:40 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:40 pc-mtodorov kernel: leaked reference. Mar 14 20:58:40 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:40 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:40 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:40 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:40 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:40 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:40 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:40 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:40 pc-mtodorov kernel: leaked reference. Mar 14 20:58:40 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:40 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:40 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:40 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:40 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:40 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:40 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:40 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:40 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:40 pc-mtodorov kernel: leaked reference. Mar 14 20:58:40 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:40 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:40 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:40 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:40 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:40 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:40 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:40 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:40 pc-mtodorov kernel: leaked reference. Mar 14 20:58:40 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:40 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:40 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:40 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:40 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:40 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:40 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:40 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:50 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:50 pc-mtodorov kernel: leaked reference. Mar 14 20:58:50 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:50 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:50 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:50 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:50 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:50 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:50 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:50 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:50 pc-mtodorov kernel: leaked reference. Mar 14 20:58:50 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:50 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:50 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:50 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:50 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:50 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:50 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:50 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:50 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:58:50 pc-mtodorov kernel: leaked reference. Mar 14 20:58:50 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:58:50 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:58:50 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:58:50 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:50 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:50 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:50 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:50 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:50 pc-mtodorov kernel: leaked reference. Mar 14 20:58:50 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:58:50 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:58:50 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:58:50 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:58:50 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:58:50 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:58:50 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:58:50 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:58:57 pc-mtodorov kernel: kmemleak: 1 new suspected memory leaks (see /sys/kernel/debug/kmemleak) Mar 14 20:59:00 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:59:00 pc-mtodorov kernel: leaked reference. Mar 14 20:59:00 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:59:00 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:59:00 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:59:00 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:00 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:00 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:00 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:00 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:00 pc-mtodorov kernel: leaked reference. Mar 14 20:59:00 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:59:00 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:59:00 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:59:00 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:00 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:00 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:00 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:00 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:01 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:59:01 pc-mtodorov kernel: leaked reference. Mar 14 20:59:01 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:59:01 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:59:01 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:59:01 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:01 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:01 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:01 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:01 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:01 pc-mtodorov kernel: leaked reference. Mar 14 20:59:01 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:59:01 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:59:01 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:59:01 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:01 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:01 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:01 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:01 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:10 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:59:10 pc-mtodorov kernel: leaked reference. Mar 14 20:59:10 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:59:10 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:59:10 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:59:10 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:10 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:10 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:10 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:10 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:10 pc-mtodorov kernel: leaked reference. Mar 14 20:59:10 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:59:10 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:59:10 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:59:10 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:10 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:10 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:10 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:10 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:11 pc-mtodorov kernel: unregister_netdevice: waiting for tap0 to become free. Usage count = 3 Mar 14 20:59:11 pc-mtodorov kernel: leaked reference. Mar 14 20:59:11 pc-mtodorov kernel: net_rx_queue_update_kobjects+0x75/0x1d0 Mar 14 20:59:11 pc-mtodorov kernel: netif_set_real_num_rx_queues+0x5b/0xb0 Mar 14 20:59:11 pc-mtodorov kernel: tun_attach+0x1ec/0x5a0 Mar 14 20:59:11 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:11 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:11 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:11 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:11 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc Mar 14 20:59:11 pc-mtodorov kernel: leaked reference. Mar 14 20:59:11 pc-mtodorov kernel: netdev_queue_update_kobjects+0x86/0x190 Mar 14 20:59:11 pc-mtodorov kernel: netif_set_real_num_tx_queues+0x86/0x250 Mar 14 20:59:11 pc-mtodorov kernel: tun_attach+0x1d7/0x5a0 Mar 14 20:59:11 pc-mtodorov kernel: __tun_chr_ioctl+0xa58/0x17d0 Mar 14 20:59:11 pc-mtodorov kernel: tun_chr_ioctl+0x17/0x20 Mar 14 20:59:11 pc-mtodorov kernel: __x64_sys_ioctl+0x97/0xd0 Mar 14 20:59:11 pc-mtodorov kernel: do_syscall_64+0x5c/0x90 Mar 14 20:59:11 pc-mtodorov kernel: entry_SYSCALL_64_after_hwframe+0x72/0xdc [root@pc-mtodorov marvin]#

I see those "leaked reference" lines are being printed here: https://elixir.bootlin.com/linux/v6.3-rc2/source/lib/ref_tracker.c#L55

However, it is beyond the scope of my knowledge to track the actual leak.

Hope this helps.

Best regards, Mirsad