syzbot

netdevsim netdevsim5 eth0: set [1, 0] type 2 family 0 port 6081 - 0
==================================================================
BUG: KCSAN: data-race in console_flush_all / console_flush_all

write to 0xffffffff86a25cd8 of 8 bytes by task 15955 on cpu 1:
 console_emit_next_record kernel/printk/printk.c:3090 [inline]
 console_flush_one_record kernel/printk/printk.c:3215 [inline]
 console_flush_all+0x38a/0x6c0 kernel/printk/printk.c:3289
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0x97/0x270 kernel/printk/printk.c:3359
 vprintk_emit+0x39f/0x5c0 kernel/printk/printk.c:2426
 vprintk_default+0x26/0x30 kernel/printk/printk.c:2441
 vprintk+0x1d/0x30 kernel/printk/printk_safe.c:82
 _printk+0x79/0xa0 kernel/printk/printk.c:2451
 isofs_read_inode fs/isofs/inode.c:1383 [inline]
 __isofs_iget+0xfe9/0x1100 fs/isofs/inode.c:1524
 isofs_iget fs/isofs/isofs.h:135 [inline]
 isofs_get_blocks+0x185/0x490 fs/isofs/inode.c:1069
 isofs_get_block fs/isofs/inode.c:1122 [inline]
 isofs_bmap fs/isofs/inode.c:1133 [inline]
 isofs_bread+0x5b/0x100 fs/isofs/inode.c:1141
 isofs_find_entry fs/isofs/namei.c:59 [inline]
 isofs_lookup+0x1a8/0x930 fs/isofs/namei.c:165
 __lookup_slow+0x193/0x250 fs/namei.c:1866
 lookup_slow+0x3c/0x60 fs/namei.c:1883
 walk_component fs/namei.c:2229 [inline]
 lookup_last fs/namei.c:2730 [inline]
 path_lookupat+0x2f7/0x500 fs/namei.c:2754
 filename_lookup+0x147/0x340 fs/namei.c:2783
 kern_path+0x3b/0x130 fs/namei.c:2996
 find_autofs_mount fs/autofs/dev-ioctl.c:196 [inline]
 autofs_dev_ioctl_ismountpoint+0x12d/0x4c0 fs/autofs/dev-ioctl.c:596
 _autofs_dev_ioctl fs/autofs/dev-ioctl.c:746 [inline]
 autofs_dev_ioctl+0x354/0x6a0 fs/autofs/dev-ioctl.c:762
 vfs_ioctl fs/ioctl.c:51 [inline]
 __do_sys_ioctl fs/ioctl.c:597 [inline]
 __se_sys_ioctl+0xce/0x140 fs/ioctl.c:583
 __x64_sys_ioctl+0x43/0x50 fs/ioctl.c:583
 x64_sys_call+0x14b0/0x3000 arch/x86/include/generated/asm/syscalls_64.h:17
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xca/0x2b0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffffffff86a25cd8 of 8 bytes by task 12 on cpu 0:
 console_flush_one_record kernel/printk/printk.c:3216 [inline]
 console_flush_all+0x549/0x6c0 kernel/printk/printk.c:3289
 __console_flush_and_unlock kernel/printk/printk.c:3319 [inline]
 console_unlock+0x97/0x270 kernel/printk/printk.c:3359
 vprintk_emit+0x39f/0x5c0 kernel/printk/printk.c:2426
 dev_vprintk_emit+0x242/0x2a0 drivers/base/core.c:4914
 dev_printk_emit+0x84/0xb0 drivers/base/core.c:4925
 __netdev_printk+0x34b/0x370 net/core/dev.c:12903
 netdev_info+0x9b/0xd0 net/core/dev.c:12958
 nsim_udp_tunnel_set_port+0x135/0x150 drivers/net/netdevsim/udp_tunnels.c:31
 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+0x567/0x9c0 net/ipv4/udp_tunnel_nic.c:292
 udp_tunnel_nic_device_sync_work+0x5d/0x580 net/ipv4/udp_tunnel_nic.c:740
 process_one_work kernel/workqueue.c:3257 [inline]
 process_scheduled_works+0x4ce/0x9d0 kernel/workqueue.c:3340
 worker_thread+0x582/0x770 kernel/workqueue.c:3421
 kthread+0x489/0x510 kernel/kthread.c:463
 ret_from_fork+0x149/0x290 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246

value changed: 0x0000000000002831 -> 0x0000000000002832

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 12 Comm: kworker/u8:0 Tainted: G        W           syzkaller #0 PREEMPT(voluntary) 
Tainted: [W]=WARN
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025
Workqueue: udp_tunnel_nic udp_tunnel_nic_device_sync_work
==================================================================
netdevsim netdevsim5 eth1: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 eth2: set [1, 0] type 2 family 0 port 6081 - 0
netdevsim netdevsim5 eth3: set [1, 0] type 2 family 0 port 6081 - 0