loop2: detected capacity change from 0 to 128 vfat: Unknown parameter '000000000000000000006ɲ  1s{T6+`N+%{aZI֝`1 wMOAy%(4abV۾8_Kׂ(W6>$BZ' ================================================================== BUG: KCSAN: data-race in data_push_tail / number write to 0xffffffff893c2708 of 1 bytes by task 12636 on cpu 1: number+0x865/0xb90 lib/vsprintf.c:573 vsnprintf+0x64e/0x860 lib/vsprintf.c:2912 va_format lib/vsprintf.c:1723 [inline] pointer+0x821/0xcb0 lib/vsprintf.c:2569 vsnprintf+0x491/0x860 lib/vsprintf.c:2952 vscnprintf+0x41/0x90 lib/vsprintf.c:3013 printk_sprint+0x30/0x2e0 kernel/printk/printk.c:2222 vprintk_store+0x57b/0x910 kernel/printk/printk.c:2364 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 dev_vprintk_emit+0x242/0x2a0 drivers/base/core.c:4913 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4924 __netdev_printk+0x34b/0x370 net/core/dev.c:12932 netdev_info+0xa6/0xd0 net/core/dev.c:12987 nsim_udp_tunnel_unset_port+0x190/0x1b0 drivers/net/netdevsim/udp_tunnels.c:59 udp_tunnel_nic_device_sync_one net/ipv4/udp_tunnel_nic.c:-1 [inline] udp_tunnel_nic_device_sync_by_port net/ipv4/udp_tunnel_nic.c:249 [inline] __udp_tunnel_nic_device_sync+0x575/0x9b0 net/ipv4/udp_tunnel_nic.c:292 udp_tunnel_nic_flush+0x21b/0x300 net/ipv4/udp_tunnel_nic.c:694 udp_tunnel_nic_unregister net/ipv4/udp_tunnel_nic.c:901 [inline] udp_tunnel_nic_netdevice_event+0x8c0/0xd70 net/ipv4/udp_tunnel_nic.c:942 notifier_call_chain kernel/notifier.c:85 [inline] raw_notifier_call_chain+0x83/0x1c0 kernel/notifier.c:453 call_netdevice_notifiers_info net/core/dev.c:2249 [inline] call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] unregister_netdevice_many_notify+0xedb/0x1710 net/core/dev.c:12412 unregister_netdevice_many net/core/dev.c:12475 [inline] unregister_netdevice_queue+0x1cd/0x200 net/core/dev.c:12289 unregister_netdevice include/linux/netdevice.h:3408 [inline] nsim_destroy+0x108/0x480 drivers/net/netdevsim/netdev.c:1182 __nsim_dev_port_del+0xcf/0x110 drivers/net/netdevsim/dev.c:1528 nsim_dev_port_del_all drivers/net/netdevsim/dev.c:1540 [inline] nsim_dev_reload_destroy+0x1a3/0x2c0 drivers/net/netdevsim/dev.c:1764 nsim_dev_reload_down+0x67/0x80 drivers/net/netdevsim/dev.c:1038 devlink_reload+0xad/0x590 net/devlink/dev.c:461 devlink_pernet_pre_exit+0xdb/0x230 net/devlink/core.c:507 ops_pre_exit_list net/core/net_namespace.c:161 [inline] ops_undo_list+0xb5/0x420 net/core/net_namespace.c:234 cleanup_net+0x37c/0x5b0 net/core/net_namespace.c:704 process_one_work kernel/workqueue.c:3275 [inline] process_scheduled_works+0x4de/0x9e0 kernel/workqueue.c:3358 worker_thread+0x581/0x770 kernel/workqueue.c:3439 kthread+0x22a/0x280 kernel/kthread.c:467 ret_from_fork+0x150/0x360 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 read to 0xffffffff893c2708 of 8 bytes by task 26268 on cpu 0: data_make_reusable kernel/printk/printk_ringbuffer.c:608 [inline] data_push_tail+0x100/0x470 kernel/printk/printk_ringbuffer.c:693 data_alloc+0x11b/0x390 kernel/printk/printk_ringbuffer.c:1089 prb_reserve+0x8d7/0xae0 kernel/printk/printk_ringbuffer.c:1724 vprintk_store+0x54a/0x910 kernel/printk/printk.c:2354 vprintk_emit+0x1a4/0x600 kernel/printk/printk.c:2455 vprintk_default+0x26/0x30 kernel/printk/printk.c:2494 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82 _printk+0x79/0xa0 kernel/printk/printk.c:2504 logfc+0x2d5/0x2e0 fs/fs_context.c:-1 vfs_parse_fs_param+0x1e0/0x2a0 fs/fs_context.c:144 vfs_parse_fs_qstr fs/fs_context.c:173 [inline] vfs_parse_fs_string include/linux/fs_context.h:142 [inline] vfs_parse_monolithic_sep+0x1e6/0x270 fs/fs_context.c:213 generic_parse_monolithic+0x24/0x30 fs/fs_context.c:241 parse_monolithic_mount_data+0x46/0x60 fs/fs_context.c:520 do_new_mount+0x24e/0x8d0 fs/namespace.c:3835 path_mount+0x4d0/0xbc0 fs/namespace.c:4159 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x28c/0x2e0 fs/namespace.c:4338 __x64_sys_mount+0x67/0x80 fs/namespace.c:4338 x64_sys_call+0x2d61/0x3020 arch/x86/include/generated/asm/syscalls_64.h:166 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x12c/0x370 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f value changed: 0x00000000fffff9d2 -> 0x7974205d31202c31 Reported by Kernel Concurrency Sanitizer on: CPU: 0 UID: 0 PID: 26268 Comm: syz.2.2946 Tainted: G W syzkaller #0 PREEMPT(full) Tainted: [W]=WARN Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 ================================================================== lo speed is unknown, defaulting to 1000