====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.3.710/7694 is trying to acquire lock: ffff888073ab9450 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xd4/0xa60 kernel/workqueue.c:3072 but task is already holding lock: ffff888073ab8130 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x251/0x530 net/smc/af_smc.c:-1 which lock already depends on the new lock. the existing dependency chain (in reverse order) is: -> #1 (sk_lock-AF_SMC/1){+.+.}-{0:0}: lock_sock_nested+0x44/0x100 net/core/sock.c:3488 smc_listen_out+0x109/0x3d0 net/smc/af_smc.c:1865 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 -> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __flush_work+0xed/0xa60 kernel/workqueue.c:3072 __cancel_work_timer+0x3ac/0x520 kernel/workqueue.c:3163 smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29 __smc_release+0x661/0x7d0 net/smc/af_smc.c:300 smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1798 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xb00/0xea0 net/smc/smc_close.c:225 __smc_release+0x8d/0x7d0 net/smc/af_smc.c:276 smc_release+0x2ca/0x530 net/smc/af_smc.c:343 __sock_release net/socket.c:654 [inline] sock_close+0xd5/0x240 net/socket.c:1400 __fput+0x22c/0x920 fs/file_table.c:320 task_work_run+0x1ca/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x93e/0x2400 kernel/exit.c:880 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 other info that might help us debug this: Possible unsafe locking scenario: CPU0 CPU1 ---- ---- lock(sk_lock-AF_SMC/1); lock((work_completion)(&new_smc->smc_listen_work)); lock(sk_lock-AF_SMC/1); lock((work_completion)(&new_smc->smc_listen_work)); *** DEADLOCK *** 2 locks held by syz.3.710/7694: #0: ffff888070311a10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:758 [inline] #0: ffff888070311a10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: __sock_release net/socket.c:653 [inline] #0: ffff888070311a10 (&sb->s_type->i_mutex_key#10){+.+.}-{3:3}, at: sock_close+0x90/0x240 net/socket.c:1400 #1: ffff888073ab8130 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x251/0x530 net/smc/af_smc.c:-1 stack backtrace: CPU: 1 PID: 7694 Comm: syz.3.710 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 check_noncircular+0x274/0x310 kernel/locking/lockdep.c:2170 check_prev_add kernel/locking/lockdep.c:3090 [inline] check_prevs_add kernel/locking/lockdep.c:3209 [inline] validate_chain kernel/locking/lockdep.c:3825 [inline] __lock_acquire+0x2cf8/0x7c50 kernel/locking/lockdep.c:5049 lock_acquire+0x1b4/0x490 kernel/locking/lockdep.c:5662 __flush_work+0xed/0xa60 kernel/workqueue.c:3072 __cancel_work_timer+0x3ac/0x520 kernel/workqueue.c:3163 smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29 __smc_release+0x661/0x7d0 net/smc/af_smc.c:300 smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1798 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xb00/0xea0 net/smc/smc_close.c:225 __smc_release+0x8d/0x7d0 net/smc/af_smc.c:276 smc_release+0x2ca/0x530 net/smc/af_smc.c:343 __sock_release net/socket.c:654 [inline] sock_close+0xd5/0x240 net/socket.c:1400 __fput+0x22c/0x920 fs/file_table.c:320 task_work_run+0x1ca/0x250 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0x93e/0x2400 kernel/exit.c:880 do_group_exit+0x217/0x2d0 kernel/exit.c:1022 get_signal+0x1272/0x1350 kernel/signal.c:2871 arch_do_signal_or_restart+0xb0/0x1230 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x70/0x110 kernel/entry/common.c:174 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7ff44578ebe9 Code: Unable to access opcode bytes at 0x7ff44578ebbf. RSP: 002b:00007ff44667a038 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: fffffffffffffe00 RBX: 00007ff4459c6180 RCX: 00007ff44578ebe9 RDX: 0000000000000010 RSI: 0000200000000000 RDI: 0000000000000004 RBP: 00007ff445811e19 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ff4459c6218 R14: 00007ff4459c6180 R15: 00007fffb7cf1ee8