syzbot

nci: nci_add_new_protocol: the target found does not have the desired protocol
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BUG: KCSAN: data-race in destroy_workqueue / pwq_dec_nr_in_flight

read-write to 0xffff888118dd1b00 of 4 bytes by task 16474 on cpu 1:
 destroy_workqueue+0x85/0x7c0 kernel/workqueue.c:5867
 nci_unregister_device+0x54/0x160 net/nfc/nci/core.c:1315
 virtual_ncidev_close+0x2a/0x50 drivers/nfc/virtual_ncidev.c:172
 __fput+0x29b/0x650 fs/file_table.c:465
 ____fput+0x1c/0x30 fs/file_table.c:493
 task_work_run+0x131/0x1a0 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe4/0x100 kernel/entry/common.c:114
 exit_to_user_mode_prepare include/linux/entry-common.h:330 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:414 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:449 [inline]
 do_syscall_64+0x1d6/0x200 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888118dd1b00 of 4 bytes by task 3658 on cpu 0:
 wq_node_nr_active kernel/workqueue.c:1555 [inline]
 pwq_dec_nr_active kernel/workqueue.c:1933 [inline]
 pwq_dec_nr_in_flight+0x5c/0x6d0 kernel/workqueue.c:1994
 process_one_work kernel/workqueue.c:3295 [inline]
 process_scheduled_works+0x6a2/0x9d0 kernel/workqueue.c:3321
 worker_thread+0x582/0x770 kernel/workqueue.c:3402
 kthread+0x489/0x510 kernel/kthread.c:464
 ret_from_fork+0xda/0x150 arch/x86/kernel/process.c:148
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

value changed: 0x0006000a -> 0x0007800a

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 UID: 0 PID: 3658 Comm: kworker/u8:9 Not tainted 6.16.0-rc7-syzkaller #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
Workqueue:  0x0 (nfc2_nci_rx_wq)
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