====================================================== WARNING: possible circular locking dependency detected syzkaller #0 Not tainted ------------------------------------------------------ syz.1.151/5101 is trying to acquire lock: ffff88807d639f98 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}, at: __flush_work+0xfa/0x210 kernel/workqueue.c:3090 but task is already holding lock: ffff888025c78120 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x249/0x520 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:3258 smc_listen_out+0xd4/0x3c0 net/smc/af_smc.c:1580 smc_listen_out_connected net/smc/af_smc.c:1602 [inline] smc_listen_decline net/smc/af_smc.c:1637 [inline] smc_listen_work+0x52a/0xd10 net/smc/af_smc.c:2095 process_one_work+0x867/0xff0 kernel/workqueue.c:2310 worker_thread+0xad7/0x12a0 kernel/workqueue.c:2457 kthread+0x42e/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 -> #0 ((work_completion)(&new_smc->smc_listen_work)){+.+.}-{0:0}: check_prev_add kernel/locking/lockdep.c:3120 [inline] check_prevs_add kernel/locking/lockdep.c:3239 [inline] validate_chain kernel/locking/lockdep.c:3855 [inline] __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120 lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737 __flush_work+0x116/0x210 kernel/workqueue.c:3090 __cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3181 smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29 __smc_release+0x644/0x7b0 net/smc/af_smc.c:241 smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1523 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xae2/0xea0 net/smc/smc_close.c:222 __smc_release+0x9c/0x7b0 net/smc/af_smc.c:217 smc_release+0x2c1/0x520 net/smc/af_smc.c:284 __sock_release net/socket.c:651 [inline] sock_close+0xbf/0x210 net/socket.c:1346 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x635/0x2100 kernel/exit.c:890 do_group_exit+0x12c/0x2f0 kernel/exit.c:1004 get_signal+0x7eb/0x12e0 kernel/signal.c:2917 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:157 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 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.1.151/5101: #0: ffff88805fd9ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: inode_lock include/linux/fs.h:793 [inline] #0: ffff88805fd9ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: __sock_release net/socket.c:650 [inline] #0: ffff88805fd9ee10 (&sb->s_type->i_mutex_key#11){+.+.}-{3:3}, at: sock_close+0x82/0x210 net/socket.c:1346 #1: ffff888025c78120 (sk_lock-AF_SMC/1){+.+.}-{0:0}, at: smc_release+0x249/0x520 net/smc/af_smc.c:-1 stack backtrace: CPU: 0 PID: 5101 Comm: syz.1.151 Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/07/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 check_noncircular+0x2f8/0x400 kernel/locking/lockdep.c:2178 check_prev_add kernel/locking/lockdep.c:3120 [inline] check_prevs_add kernel/locking/lockdep.c:3239 [inline] validate_chain kernel/locking/lockdep.c:3855 [inline] __lock_acquire+0x38f7/0x7d40 kernel/locking/lockdep.c:5120 lock_acquire+0x19f/0x400 kernel/locking/lockdep.c:5737 __flush_work+0x116/0x210 kernel/workqueue.c:3090 __cancel_work_timer+0x3f4/0x560 kernel/workqueue.c:3181 smc_clcsock_release+0x5c/0xe0 net/smc/smc_close.c:29 __smc_release+0x644/0x7b0 net/smc/af_smc.c:241 smc_close_non_accepted+0xd1/0x1f0 net/smc/af_smc.c:1523 smc_close_cleanup_listen net/smc/smc_close.c:45 [inline] smc_close_active+0xae2/0xea0 net/smc/smc_close.c:222 __smc_release+0x9c/0x7b0 net/smc/af_smc.c:217 smc_release+0x2c1/0x520 net/smc/af_smc.c:284 __sock_release net/socket.c:651 [inline] sock_close+0xbf/0x210 net/socket.c:1346 __fput+0x212/0x8c0 fs/file_table.c:311 task_work_run+0x125/0x1a0 kernel/task_work.c:188 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0x635/0x2100 kernel/exit.c:890 do_group_exit+0x12c/0x2f0 kernel/exit.c:1004 get_signal+0x7eb/0x12e0 kernel/signal.c:2917 arch_do_signal_or_restart+0xe6/0x12a0 arch/x86/kernel/signal.c:867 handle_signal_work kernel/entry/common.c:157 [inline] exit_to_user_mode_loop+0x9e/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:217 __syscall_exit_to_user_mode_work kernel/entry/common.c:299 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:310 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 RIP: 0033:0x7f5564658b19 Code: Unable to access opcode bytes at RIP 0x7f5564658aef. RSP: 002b:00007f55628af028 EFLAGS: 00000246 ORIG_RAX: 000000000000002a RAX: 0000000000000000 RBX: 00007f55648defa0 RCX: 00007f5564658b19 RDX: 0000000000000010 RSI: 0000200000000080 RDI: 0000000000000004 RBP: 00007f55646f0b70 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 00007f55648df038 R14: 00007f55648defa0 R15: 00007ffe4276a0c8