dvmrp0 (unregistering): left allmulticast mode
==================================================================
BUG: KCSAN: data-race in data_alloc / prb_reserve

write to 0xffffffff866832f0 of 8 bytes by task 19666 on cpu 1:
 data_alloc+0x291/0x2c0 kernel/printk/printk_ringbuffer.c:1096
 prb_reserve+0x85e/0xb60 kernel/printk/printk_ringbuffer.c:1669
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 p9_fd_create_tcp+0x418/0x470 net/9p/trans_fd.c:1036
 p9_client_create+0x59a/0xaf0 net/9p/client.c:1017
 v9fs_session_init+0xf9/0xda0 fs/9p/v9fs.c:410
 v9fs_mount+0x69/0x570 fs/9p/vfs_super.c:122
 legacy_get_tree+0x77/0xd0 fs/fs_context.c:662
 vfs_get_tree+0x56/0x1e0 fs/super.c:1814
 do_new_mount+0x227/0x690 fs/namespace.c:3507
 path_mount+0x49b/0xb30 fs/namespace.c:3834
 do_mount fs/namespace.c:3847 [inline]
 __do_sys_mount fs/namespace.c:4057 [inline]
 __se_sys_mount+0x27c/0x2d0 fs/namespace.c:4034
 __x64_sys_mount+0x67/0x80 fs/namespace.c:4034
 x64_sys_call+0x2c84/0x2dc0 arch/x86/include/generated/asm/syscalls_64.h:166
 do_syscall_x64 arch/x86/entry/common.c:52 [inline]
 do_syscall_64+0xc9/0x1c0 arch/x86/entry/common.c:83
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff866832f0 of 8 bytes by task 4968 on cpu 0:
 desc_read kernel/printk/printk_ringbuffer.c:482 [inline]
 desc_push_tail kernel/printk/printk_ringbuffer.c:778 [inline]
 desc_reserve kernel/printk/printk_ringbuffer.c:924 [inline]
 prb_reserve+0x235/0xb60 kernel/printk/printk_ringbuffer.c:1619
 vprintk_store+0x558/0x870 kernel/printk/printk.c:2326
 vprintk_emit+0x15e/0x680 kernel/printk/printk.c:2408
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2447
 vprintk+0x75/0x80 kernel/printk/printk_safe.c:86
 _printk+0x7a/0xa0 kernel/printk/printk.c:2457
 __netdev_printk+0x2d1/0x3e0 net/core/dev.c:11946
 netdev_info+0x99/0xc0 net/core/dev.c:11993
 __bond_release_one+0x345/0xa10 drivers/net/bonding/bond_main.c:2547
 bond_uninit+0x1b3/0x320 drivers/net/bonding/bond_main.c:6070
 unregister_netdevice_many_notify+0xc9d/0x11b0 net/core/dev.c:11548
 unregister_netdevice_many+0x19/0x20 net/core/dev.c:11590
 cleanup_net+0x411/0x810 net/core/net_namespace.c:627
 process_one_work kernel/workqueue.c:3229 [inline]
 process_scheduled_works+0x483/0x9a0 kernel/workqueue.c:3310
 worker_thread+0x51d/0x6f0 kernel/workqueue.c:3391
 kthread+0x1d1/0x210 kernel/kthread.c:389
 ret_from_fork+0x4b/0x60 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244

value changed: 0x000000000002e078 -> 0x00000000000e0b10

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 4968 Comm: kworker/u8:8 Not tainted 6.13.0-rc1-syzkaller-00378-g62b5a46999c7 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/13/2024
Workqueue: netns cleanup_net
==================================================================
bond0 (unregistering): (slave bond_slave_0): Releasing backup interface
bond0 (unregistering): (slave bond_slave_1): Releasing backup interface
bond0 (unregistering): Released all slaves
hsr_slave_0: left promiscuous mode
hsr_slave_1: left promiscuous mode
batman_adv: batadv0: Interface deactivated: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_0
batman_adv: batadv0: Removing interface: batadv_slave_1
veth1_macvtap: left promiscuous mode
veth0_macvtap: left promiscuous mode
veth1_vlan: left promiscuous mode
veth0_vlan: left promiscuous mode
pim6reg (unregistering): left allmulticast mode
team0 (unregistering): Port device team_slave_1 removed
team0 (unregistering): Port device team_slave_0 removed